GE2021 - Vidyarthiplus

GE2021 STUDY MATERIAL DEPT.OF CHEMISTRY

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ENVIRONMENTAL SCIENCE AND ENGINEERING

UNIT – I

ENVIRONMENT,ECOSYSTEMS AND BIODIVERSITY

DEFINITION:

The term Environment coined by Jacob Van Uerkul (1864 – 1944) is derived from French word “environ” or “environes” meaning “around”, “round about”, “to surround” and “ to encompass”. The sum of total of all the living and non living things around influencing one another is known as environment.

Environment is defined as all external conditions and factors, living and nonliving (chemicals and

energy), that affect an organism or other specified system during its lifetime.

According to IUCN(International Union for Conservation of Nature), Environmental studies is the

process of recognizing values and clarifying concepts in order to develop skills and attitudes necessary to

understand and appreciate the interrelatedness among man, his culture and his bio physical surroundings.

Environmental studies entail practice in decision making and self formulation of a code of

behaviour about issues concurring environment policy.

Environmental Engineering is the application of engineering principles to the protection and

enhancement of the quality of the environment and to the enhancement and protection of public health

and welfare.

Environmental science is the study of the environment, its biotic and abiotic components and

their inter relationship.

Environmental science is a study of how the earth works, how we interact with the earth and how

to deal with environmental problems.

Environmental science is an interdisciplinary study that uses information from the physical

sciences (such as Biology, chemistry, and geology) and social sciences (such as economics, politics, and

ethics) to learn how the earth works, how humans interact with the earth, and how to deal with the

environmental problems we face.

Ecology is a biological science that studies the relationships between living organisms and their

environment.

Environmentalism is a social movement dedicated to protecting the earth’s life support systems for us and other species.

SCOPE

The scope and objective of environment studies is “to cultivate our public to be aware and concerned about total environment and its associated problems and commitment to work individually and

collectively towards solutions of current problems and the prevention of new ones.

OBJECTIVES

To reduce the degree of uncertainty in life and living

To bring surface linkages between development and environment

To find ways of integrating environmental consideration in developmental planning

SCOPE OF ENVIRONMENTAL STUDIES:

To get an awareness and sensitivity to the total environment and its allied problems.

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Acquiring basic understanding of total environment problems and the responsible presence of

humanity in it

Inculcating a set of social values and strong feelings of environment concern.

To motivate the mankind in active participation in environment protection and improvement.

Developing skills to identify and solve environmental related problems.

Ability to evaluate environmental programmes in terms of ecological, economic social, aesthetic

and educational factors.

Extend help to develop a sense of responsibility and urgency regarding environmental problem

and providing an opportunity to ensure appropriate action plans to solve them.

To promote the value and necessity of local, national, international solution for environmental

problems.

To help the public know the real causes of environmental problems and contribute towards solving

them.

To focus on plans for growth and development through environmental aspects.

To give a clear picture about the current potential of resources and environmental situations.

An environmental study is a long process of learning and it makes the man a more responsible

citizen. By this man can understand how to create a healthier environment.

Environmental studies are a continuous process aimed at creating an environmentally responsible

society.

IMPROTANCE OF ENVIRONMENTAL STUDIES:

Through environmental studies one can understand how attitudes and values can affect the

environment at present and as well as in the future.

Environmental studies has a direct relation to the quality of life we live

Environmental studies relates to our surroundings which we observe daily but never think

seriously.

It not only gives more information about environment, but it implies getting right attitudes and

values suitable to environmental protection.

By teaching environment studies the people will understand the concept of need of development

without causing destruction to environment.

Environmental studies develop a concern and respect for the environment

It informs people as to how they can play an effective role in protecting the environment by

demanding changes in laws and enforcement systems.

NEED FOR PUBLIC AWARNESS

There is a Chinese proverb “If you plan for one year, plant rice, if you plan for ten years, plant trees and if you plan for hundred years, educate people.”

On conference on Environment and development held in Rio de Janerio in 1992 popularly known

as “Earth summit” and it is followed by the “World summit on sustainable development” at Johannes burg in 2002 have highlighted key issues of global environmental concern and have attracted the attention

of the general public towards the deteriorating environment.

Any government at its own level cannot achieve the goals of sustainable development until the




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public has a participatory role in it.

Public participation is possible only when the public is aware about the ecological and

environmental issues.

Drive by the government to ban the littering polythene cannot be successful until the public

understands the environment implication of the same.

Public has to be educated about the fact that if we are degrading our environment, we are actually

harming our own selves.

We are the part of the complex net work, where every component is interlinked.

The public participation is useful in law making process and controlling the pollution activities

Thus, the public participation plays a major role in the effective environmental management

It is all the more important to educate the people that sometimes the adverse impact of

environment are not experienced or noticed until a threshold is crossed. So we may be caught

unawares by a disaster.

If we want to manage our planet earth, we have to make all the persons environmentally educated.

Environment is wrongly taken as “fashion” hardly realizing that it is our real life situation and our

sustenance and security are at stake.

Restoration is expected in the next 40 – 50 years, if we stop polluting the earth now.

Few have clean ideas about what needs to be done.

Environmental awareness campaigns exploited politically

ENVRIONMENTAL AWARNESS IS ESSENTIAL TO

1. Protect the atmosphere

2. Protect the land resources.

3. Conserve the biological diversity

4. Manage the bio – technology and hazardous waste.

5. Prevent illegal movement of toxic product & wastes.

6. Improve the living standards.

7. Check Environmental degradation.

ECOSYSTEMS

Ecology (from the greek word oikos - “house” or place to live and logos - ‘study of”) is the study of how organisms interact with one another and with their non living environment.

The term ecosystem was proposed by A.G.Tansley in 1935 who defined it as “the system resulting from the integration of all the living and non living factors of environment”

Kinds of ecosystem:

1. Natural ecosystem:-

These operate by themselves under natural conditions without any major interference by

man.

I) Terrestrial

II) Aquatic

a) Freshwater

b) Marine




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2. Artificial ecosystem: - These are maintained artificially by man, where by addition of energy and

planned manipulations natural balance is disturbed regularly.

Structure and Function of an ecosystem:-

The two major aspects of an ecosystem are the structure and function.

By structure we mean

i) The composition of Biological community including species, numbers, biomass, life history

and distribution in space.

ii) The quantity and distribution of non-living materials such as nutrients, water etc.

iii) The range or gradient of conditions of existence such as temperature, light etc.

By Function we mean

i) The rate of Biological energy flow.

ii) The rate of materials or nutrient cycle

iii) Biological or ecological regulation (including both regulation of organisms by environment

and regulation of environment by organisms.

Thus in any ecosystem, structure and function are studied together.

Ecosystem concepts and components

Earth consists of large masses of land and vast expanse of oceans. Biologists classified terrestrial portion

of the biosphere into biomes. They are large regions such as forests, deserts, and grasslands characterized

by a distinct climate and specific life forms adapted to it.

Climate is the long term patterns of weather. It is the main factor determining what type of life, especially

what plants will thrive in a given land area.

Each biome consists of a patch work of many different ecosystems whose communities have adapted to

differences in climate, soil and other factors through the biome.

Marine and fresh water portions of biosphere can be divided into aquatic life zones each containing

numerous ecosystems.

Freshwater life zones – lakes, ponds, streams, rivers

Ocean life zone – estuaries, coastal lines, coral reef & deep oceans.

Some important definitions

Species: Organism can be classified into species or groups of organisms that resemble one another in

appearance, behavior, chemistry and genetic make up.

Population: A population consists of a group of interacting individuals of the same species that occupy a

specific area at the same time.

Habitat: The place where a population (an individual organism) normally lives is its habitat.

Community: Populations of the different species occupying a particular place makeup a community or

Biological community. It is a complex network of plants animals and micro organisms.

Ecosystem: An ecosystem is a community of different species interacting with one another and with their

nonliving environment of matter and energy.

Biosphere: All of the earth’s ecosystem together makeup the biosphere. Components of an ecosystem

Two types of components




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a) Abiotic component consists of nonliving chemical and physical components such as water

air, nutrients in the soil or water and solar energy

b) Biotic component consists of living and dead plants, animals and micro organism.

Major physical & chemical components of ecosystem Terrestrial Aquatic

* Sunlight * Light penetration

* Temperature * Water currents

* Precipitation * Dissolved nutrient concentration

*Wind * Suspended solids

* Latitude * Salinity

* Altitude

* Fire frequency

* Soil

Each population in an ecosystem has a range of tolerance to variations in its physical & chemical

environment.

Limiting Factor Principle

Too much or too little of any abiotic factor can limit or prevent growth of a population, even if all

other factors are all or near the optimum range of tolerance.

On land, precipitation often is limiting factor.Soil nutrients act as a limiting factor.

Important limiting factors for aquatic ecosystem include temperature, sunlight, dissolved oxygen content,

nutrient availability and salinity.

Biological Component (biotic)

Living organisms in ecosystem based on how they get food, are classified into

i) Producers (autotrophs)

ii) Consumers (heterotrophs)

Producers/Autotrophs can make their own food from the compounds that are obtained from their

environment.

Producers are the source of all food in an ecosystem

Most Producers capture sunlight to make carbohydrates by photosynthesis

6 CO2+6H2O+Solarenergy C6H12O6+6O2

A few producers, mostly specialized bacteria can convert simple compounds from their environment into

more complex nutrient compounds without sunlight a process called chemosynthesis

Consumers/Heterotrophs are the organisms, which depend directly or indirectly on food provided by

producers.

All other organisms in an ecosystem are consumers or heterotrophs which get their energy and nutrient by

feeding on other organism or their remains. Consumers are classified as follows

i) Herbivores/Primary consumers: They feed directly on producers are known as primary

consumers (Rabbit, cow)

ii) Carnivores: They feed on other consumers. If they feed on herbivores they are called

secondary consumers and if they feed on other carnivores are known as tertiary consumers.

iii) Omnivores: They feed on both plants and animals.




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iv) Detritivores (or) Detritus feeders: They feed on the parts of dead organisms, wastes of

living organism, their cast off and partially decomposed matter eg beetles, termites and crab.

v) Decomposers: They are specialized consumers that recycle organic matter in ecosystem.

They do this by breaking down dead organic material to get nutrients and releasing the

resulting simple inorganic compounds into the soil and water where they can be taken up as

nutrients by producers.

Producers, consumers and decomposers use the chemical energy stored in glucose and other organic

compounds to fuel their life process. In most cells this energy is released by aerobic respiration which

uses oxygen to convert organism’s nutrients back into CO2 & H2O.

C6H12O6+6CO2 6CO2+6H20+energy

Some decomposers get the energy they need by breaking down glucose in the absence of oxygen. This

form of cellular respiration is known as anaerobic respiration or fermentation. The end product of this

process is compounds such as CH4, C2H5OH, CH3COOH and H2S.

The survival of any individual organisms depends on the flow of matter and energy through its body.

However an ecosystem as a whole survives primarily through a combination of matter recycling and one

way energy flow.

Food chain & Food web

The sequence of eating and being eaten in an ecosystem is known as food chain. It determines how

energy and nutrient move from one organism to another through an ecosystem.

Ecologists assign each organism in an ecosystem to a feeding level or trophiclevel, depending on whether

it is a producer or a consumer and on what it eats or decomposes.

Producers belong to first trophic level, primary consumers to the second trophic level and secondary

consumers to the third and so on.

Detritivores process detritus from all trophic levels.

Characteristics of Grazing Food Chain

a) These are directly dependent upon solar radiations as the primary source of energy and the producers

(green plants) synthesize their plant biomass by the process of photosynthesis. Producers form the first

trophic level.

b) Herbivores or primary consumers eat upon the producers and form the second trophic level.

c) Herbivores are in-turn eaten by different categories of carnivores forming the higher trophic levels.

d) Grazing food chains are longer food chains and they always end at decomposer level.

Grazing type food chain




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Detritus food chain, the dominant primary consumers (herbivores) are the insects, which usually consume

less than ten percent of the net primary production. The major remaining portion of more than 90% is

consumed later as dead plant material by small detritus feeding organisms such as micro arthropods,

oligochaetes and microorganisms.

The detritus feeding organisms process the detritus in their gut by reducing it into small pieces, digesting

it partially or completely, thus making organic material available for bacterial or fungal attack. These

microorganisms also act as food for many soil animals.

This food chain is decomposer organism based and is called 'detritus or decomposer food chain'.

Characteristics of Detritus Food Chain

a) Primary source of energy is dead organic matter called 'detritus' which are fallen leaves, plant parts or

dead animal bodies.

b) Primary consumers are 'detritivores' including protozoans, bacteria, fungi, etc which feed upon the

detritus saprophytically.




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c) Detritivores are inturn eaten by secondary consumers such as insect larvae, nematodes, etc.

d) Detritus food chains are generally shorter than grazing food chains

e) In nature, detritus food chains are indispensable as the dead organic matter of grazing food chain is

acted upon by the detritivores to recycle the inorganic elements into the ecosystem.

Detritus food chain

Differences between Grazing and Detritus food Chains

Detritus Detritivores Detritivores Consumers Small

Carnivores

Large

Carnivores

Mangrove Fallen

Leaves and Dead

Bodies

Fungi,Bacteria

and Protozoans

Insect Larvae,Certain

Crustaceans,Molluscs and

Fishes

Minnows Small

game fish etc.

Large

Fish,Fish eating

Birds




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Real ecosystems are more complex than this. Most consumers feed on more than one type of organisms

and most organisms are eaten by more than one type of consumers.

Because most species participate in several different food chains the organisms in most ecosystem form a

complex network of interconnected food chains called a food web.

Food Web is a network of food chains where different types of organisms are connected at different

trophic level so that there are a numbers of options of eating and being eaten at each trophic level.

Ecological pyramids

Graphical representation of trophic structure & function of an ecosystem starting with producers at the

base and successive trophic levels forming the apex is known as ecological pyramid. It is of three types.

Pyramid of numbers:

It represents the number of individual organisms at each trophic level.

We may have upright or inverted pyramid of numbers depending upon the type of ecosystem and food

chain.

In grassland, grasses are small in size and very large in numbers so the producers form a broad base. The

herbivores in a grass lands are insects while tertiary carnivores are hawks or other birds which are

gradually less and less in number and hence the pyramid apex becomes gradually narrower forming an

upright pyramid.

TERTIARY CONSUMERS

SECONDARY CONSUMERS

PRIMARY CONSUMERS

PRODUCERS

In a forest ecosystem, big trees are the producers which are less in number. A large number of herbivores

and form much broader middle level. The secondary consumers like for snakes etc are less in number &

top carnivores like lion, tiger are stall smaller in number.

TERTIARY CONSUMERS

Characters Grazing food

chain Detritus food chain

Primary source of

energy

Solar

radiations Detritus

First trophic level All herbivores Detritivores (a mixed group in terms of trophic levels and may be

herbivores, omnivores and primary carnivores)

Size Long-sized

chains Small-sized chains

INSECTS

SNAKE

GRASSES

HAWK

FOX

LION




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SECONDARY CONSUMERS

PRIMARY CONSUMERS

PRODUCERS

Parsitic food chain shows an inverted pyramid of number. The producers like a few big trees harbours

fruit eating birds acting like herbivores which are larger in number. A much higher number of lice, bugs

etc grow as parasites on these birds while a still greater number of hyperparasites like bugs, fleas and

microbes feed upon them, thus making an inverted pyramid.

HYPER PARASITE

PARASITE

PRIMARY CONSUMERS

PRODUCERS

Pyramid of Biomass:

It is based upon the total biomass at each trophic level in a food chain.

The pyramid of Biomass can also be upright or inverted.

The pyramid of biomass in a forest is upright in contrast to its pyramid of numbers. This is because the

producers accumulate a huge biomass while the consumers total biomass feeding on them declines at

higher trophic levels resulting in broad base and narrowing top.

FLEAS,MICROBES

TREE

BIRDS

LICE,BUGS

INSECTS,BIRDS

BIG TREES




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The pond ecosystem shows an inverted pyramid of Biomass the total biomass of producer is much less as

compared to Herbivores (Zooplankton, insects), carnivores and tertiary carnivores. Thus the pyramid

takes an inverted shape with narrow base & broad apex.

Pyramid of energy:

The amount of energy present at each trophic level is considered for this type of pyramid.




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Pyramid of energy gives the best representation of the trophic relationships and it is always upright.

At every successive trophic level there is a huge loss of energy in the form of heat, respiration etc. Thus

at each next higher level only 10% of the energy passes on. Hence there is a sharp decline in energy level

of each successive trophic level as we move from producer to carnivores.

Energy flow in an ecosystem

Each trophic level in a food chain or web contains a certain amount of biomass, the dry weight of all

organic matter contained in its organisms.

In a food chain or web, the chemical energy stored in Biomass is transferred from one trophic level to

another.

With each transfer some usable energy is degraded and lost to the environment as low quality heat. Thus

only a small portion of what is eaten and digested is actually converted into an organisms bodily material

or biomass, and the amount of usable energy available to each successive trophic level declines.

The percentage of usable energy transferred as biomass from one trophic level to the next is called

Ecology efficiency. It rages from 5% to 20% depending on the types of species and the ecosystem

involved, but 10% is typical.

Assuming 10% Ecological efficiency (90% loss) at each trophic transfer, if green plants in an area

manage to capture 10,000 units of energy from the sun, than only about 1000 units of energy will be

available to support herbivores and only about 100 units to support carnivores.

The more trophic levels or steps in a food chain or web, the greater the cumulative loss of usable energy

as energy flows through the various trophic le vels.

Energy flow pyramid explains why the earth can support more people if they eat at lower trophic levels by

consuming grains rather than passing such crops through another trophic level and eating grain eaters.

The large loss in energy between successive trophic levels also explains why food chains and webs rarely

have more than four or five trophic levels.




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In most cases too little energy is left after four or five transfer to support organisms feeding at these high

trophic levels. This explains why there are so few top carnivores. It also explains why such species

usually are the first to suffer when the ecosystem that support them are disrupted and why they are so

vulnerable to

extinction.

Ecological succession:-

One characteristic of all communities and ecosystems is that their structures change




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constantly in response to changing environmental conditions. The gradual change in species composition

of a given area is called Ecological succession.

During succession some species colonize on area and their populations become more numerous, whereas

populations of other species decline and may even disappear.

Ecologistrecognize two types of Ecological succession, depending on the conditions present at the

beginning of the process.

Primary succession - This involves the gradual establishment of biotic communities on nearly lifeless

ground.

Secondary succession - which involves the establishment of biotic communities in an area where some

type of biotic community is already present.

Ecological successions starting on different types of areas or substrate are named differently as follows.

i) Hydrarch (or) hydrosere:- Starting in watery area like swamp, bog and pond.

ii) Mesarch:- Starting in an area of adequate moisture.

iii) Xeraarch (or) xerosere:- starting in a dry area with little moisture they can be of the following

types.

Lithosere: Starting on a base rock

Psammosere : Starting on sand

Halosere: Starting on saline soil

Primary succession:

It begins with an essentially lifeless area where there is no soil in a terrestrial ecosystem or no

bottom sediment in an aquatic ecosystem.

Examples include base rock exposed by retreating glaciers or severe soil erosion, newly cooled lava, an

abandoned high way or parking lot or a newly created shallow pond or reservoir.

Before a community of plants can become established on land there must be soil. Depending mostly on

the climate it takes natural processes several hundred to several thousand years to produce fertile soil.

Soil formation begins when hardy pioneer species attach themselves to inhospitable patches of base rock.

Lichens & mosus which can with stand the lack of moisture and soil nutrients and extreme temperature.

As patches of soil build up and spread, eventually the community of lichens and mosses is replaced by a

new community.

Typically it consists of small perennial grasses and herbs.

These early successional plant species grow close to the ground, can establish large populations quickly

under harsh conditions and have short lives. Some of their roots penetrate the rock and help break it up

into more soil particles. The decay of their wastes and dead bodies also adds more nutrients to the soil.

After hundreds of years, the soil may be deep and fertile enough to store enough moisture and nutrients to

support the growth of less hardy mid successional plant species of herbs, grasses and low shrubs. Trees

that need lots of sunlight and are adapted to the area’s climate and soil usually replace those species. As these tree species grow and create shade, they are replaced by late successional plant species that can

tolerate shade, unless fire flooding, severe erosion, tree cutting, climate change or other natural or human

processes disturb the area, what was once bare rock becomes a complex forest community.




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MAJOR TYPES OF ECOSYSTEMS a. FOREST ECOSYSTEM Definition: It is a natural ecosystem consisting of dense growth of trees and wild animals Types:

tropical – deciduous, evergreen, wet green

Littoral and swamps Sub

tropical Characteristics:

Abiotic: soil, sun light, temperature etc Biotic :

forest trees, shrubs and animals

Structure: Producer : trees and shrubs

Consumer : Primary – elephants, deer etc. Secondary – snakes, birds, lizards etc Tertiary – lions,

tigers etc

Decomposers : fungi, bacteria Functional components: Ecological pyramids (upright)




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lions

lizards

deers

trees

GRASSLAND ECOSYSTEM: dominated by grass – few shrubs and trees are also found – rainfall average but erratic – overgrazing leads to desertification. Three types – depending on the climate

1. Tropical grass lands – found near the boarders of tropical rain forests. Eg. Savannas in Africa. Animals – Zebra, giraffes etc. – fires are common in dry seasons – termite mounds produce methane – leads to fire – high in photosynthesis – deliberate burning leads to release of high CO2 – global warming.

2. Temperate grasslands – flat and gentle slopes of hills. Very cold winter and very hot summer - dry summer fires do not allow shrubs and trees to grow – soil is quite fertile – cleaned for agriculture.

3. Polar grasslands – found in arctic polar region – organism – arctic wolf, fox, etc. – A thick layer of ice remains frozen under the soil surface throughout the year – known as permafrost – summer insects and birds appear.

Components:

Structural Components:

Abiotic: soil pH, nutrients, soil moisture, temp, climatic conditions, etc. Biotic:

grass, caterpillar, butterfly, worms, insects, birds, etc. Functional components:

Ecological pyramid




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birds

insects

Worms

grass

Energy flow:

Grass worms Insects small birds

huge birds

Decomposition

sediments c. DESERT ECOSYSTEM Types:

1. tropical desert-found in Africa-Sahara and Rajasthan –Thar

2. temperate desert-south California-Majave

3. cold desert-China-Gobi desert Characteristics:

1. Air is dry

2. Climate is hot




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3. Annual rainfall is less than 25 cm

4. Vegetation is poor d.AQUATIC ECOSYSTEM Definition:

Deals with water bodies and biotic communities present in them-Classified as fresh water and marine ecosystems. Fresh water systems are classified as lentic and lotic ecosystems. Types:

1. Pond ecosystem: Small fresh water ecosystem – seasonal in nature – organisms: algae, aquatic plants, insects, fishes etc. Ponds are very often exposed to anthropogenic pressure like cloth washing, bathing, cattle bathing, swimming etc.

2. Lake ecosystem: Big fresh water ecosystem – Zonation or stratification, especially during summer is a common one.

Top layer – shallow, warm, prone to anthropogenic activities – Littoral zone

Second layer – enough sunlight, high primary productivity – Limnetic zone

Third layer – very poor or no sunlight – Profundal zone

Eg. Dal lake in Srinagar, Naini lake in Nainital

Organisms: planktons – phytoplankton eg. Algae – zooplankton eg. Rotifers

Nektons – that swims in water eg. Fishes

Neustons – that float on the surface of water

Benthos – that attached to sediments eg. Snails

Types of lakes : Many types- oligotrophic lakes – with less nutrient content – eutrophic lakes – with very high nutrient content due to fertilizer contamination – desert salt lakes – that contains high saline water due to over evaporation – volcanic lakes – formed by water emitted from magma due to volcanic eruptions – dystrophic lakes – that contains highly acidic water (low pH) – endemic lakes – lakes that contain many endemic species – etc.

3. Streams: fresh water ecosystem where water current plays a major role. Oxygen and nutrient content

are uniform. Stream organisms have to face extreme difference in climatic conditions but they do not suffer from oxygen deficiency as pond and lake organisms. This is because large surface area of running water provides more oxygen supply. The animals have very narrow range of tolerance towards oxygen deficiency. Thus stream are worst victims of industrial pollution.




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River ecosystem: large streams flowing from mountain highlands are rivers.

Three phases: 1. mountain highlands – rushing down water fall of water – large quantity of dissolved oxygen – plants attached to rocks and fishes that require more oxygen are found. 2. Second phase – gentle slopes of hills – warmer – supports the growth of plants and fishes that require less oxygen are seen. 3. Third phase: river shapes the land – lots of silts, nutrients are brought – deposited in plains and delta – very rich in biodiversity.

4. Oceans: Gigantic reservoirs of water covering >70% of earth surface – 2,50,000 species

– huge variety of sea products, drugs etc. – provide Fe, Mg, oils, natural gas, sand etc. – major sinks of carbon di oxide – regulate biochemical cycles. Two zones: coastal zone – warm, nutrient rich, shallow – high sunlight – high primary productivity.

Open sea – away from continental shelf – vertically divided in to 3 zones. 1. euphotic zone – abundant sunlight 2. bathyal zone – dim sunlight 3. abyssal zone – dark zone – world‟s largest ecological unit.

Estuary: coastal area where river meet ocean – strongly affected by tidal actions – very rich in nutrients – very rich in biodiversity also – organisms are highly tolerant – many species are endemic – high food productivity – however to be protected from pollution.

Characteristics:

Structural Components:

Abiotic: pH, nutrients, D.O, temp, climatic conditions, etc.

Biotic: Phytoplankton, fishes, snails insects, birds, etc.

Functional components:

Ecological pyramid

birds

Worms,

fishes

phytoplankton




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Energy flow:

Phytoplankton Insects small fishes huge fishes

Decomposition

sediments




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BIODIVERSITY Some important terms of Biodiversity:

Critical link species : plays essential role in ecosystem functions

Key stone species : Species that plays a central role in controlling the

relative abundance of other species in an ecosystem

Endemism : Native or restricted to particular area

Extinct : Not existing

Endangered : In danger of extinction

Vulnerable : Likely to move into endangered category if casual factors

continue to operate

Rare : Small world population, at present they are not

endangered or vulnerable but are at risk

Threatened : Used in the conservation context for species, which are

in one of the categories endangered, vulnerable or rare

Indeterminate : Suspected of belonging to endangered, vulnerable or rare,

but for which sufficient information is currently not available

The wide variety or variability of organism is known as biodiversity. Biological diversity means

the variability among living organisms from all sources including, inter alia, terrestrial, marine and other

aquatic ecosystem and the ecological complexes of which they are part; this includes diversity within

species, between species and of ecosystems. The term biodiversity is made up of two words – ‘bio’ and ‘diversity’. ‘Bio’ means living and ‘diversity’ means variety. Estimates of the count of living species range between 5 million and 30 million, but some biologists believe the figure may be as high as 100

million. Biodiversity is central to our existence. We also use plants and animals found in natural

ecosystems to develop new drugs for the treatment of various diseases. In addition, biodiversity provides

us with many amenities; such as ornithology, ecotourism, fishing, and others. Despite the value of

biodiversity to humans, we have destroyed and are destroying natural ecosystems at such a rate that many

biologists fear that in a few decades we will cause an unprecedented number of extinctions. We are so far

from cataloguing the diversity of life on Earth that an unknown number of animals and plants will become

extinct and we will never know what we lost.

Kinds of Biodiversity

It can be divided into three hierarchical categories-genes, species, and living systems and which scientists

measure in different ways. Biodiversity is usually described at three levels.

1. Genetic diversity

Variations among the genes of the same species are known as genetic diversity.

2. Species Diversity

Diversity which arises due to variations among species present in specific areas is called species

diversity.

3. Ecosystem Diversity.

Ecosystem Diversity is, therefore, the diversity of habitats which include the different life forms




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within. The term also refers to the variety of eco-systems found within a bio-geographical political

boundary.

Diversity at the community level has three perspectives:-

a) Alpha Diversity (Intra community Diversity) is the diversity of organisms sharing the same

habitat.

b) Beta Diversity (Inter community diversity) is the rate of replacement of species along a gradient of

habitats

c) Gamma diversity is the diversity of habitats over a geographical area.

Biogeographical Classification of India

India is considered a biodiversity-rich nation. For botanical and geographical purposes, the Indian

subcontinent can be divided into many regions. Biogeography is the study of patterns of distribution of

organisms in space and time.

Physically the country is divided into four relatively well defined regions.

1. The Himalayan mountains

2. The Gangetic river plains

3. The southern (Deccan) plateau

4. The islands of Lakshadweep, Andaman and Nicobar

These regions are discussed in detail below.

The Himalayan Mountains in the far north include some of the highest peaks in the world. The

highest mountain in the Indian Himalayas is Kangchenjunga (8586m) which is located in Sikkim on the

border with Nepal. To the south of the main Himalayan massif lie the Lesser Himalayas, rising to 3600-

4000m, and are represented by Pir Panjal in Kashmir and Dhaula Dhar in Himachal Pradesh. Further

south, flanking the Indo-Gangetic Plain, are the Siwaliks which rise to 900 – 1,500 m.

The northern plains of India stretch from Assam in the east to Punjab in the west (a distance of

2,400 km), extending south to terminate in the saline swamplands of the Rann of Kachchh (Kutch), in the

state of Gujarat. Some of the largest rivers in India, including Ganga (Ganges), Ghaghara, Brahmaputra,

and Yamuna, flow across this region. The plains are remarkably homogenous topographically: for

hundreds of kilometers the only perceptible relief if formed by floodplain bluffs, minor natural levees and

hollows known as ‘spill patterns’ and the belts of ravines formed by gully erosion along some of the larger rivers.

The Andaman and Nicobar islands comprise several small and large islands situated near the equator.

This region has a wide range of forests from coastal vegetation to evergreen forests.




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Habitats of India

Depending of the climatic

and physical conditions,

Indian habitats can be

classified into wetland,

forest, and marine habitats.

Wetlands

India has a rich variety of

wetland habitats. The total

area of wetlands

(excluding rivers) in India

is 58,286,000 ha, or 18.4%

of the country’s total area, 70% which comprises of

areas under paddy

cultivation. Two sites –

Chilka lake (Orissa) and

Kaeoladeo National Park

(Bharatpur) – have been

designated under the Convention of Wetlands of International Importance (Ramsar Convention) as being

especially significant waterfowl habitats.

Forests

India possesses a distinct identity because of the great diversity of its natural ecosystems. The panorama

of Indian forests ranges from evergreen tropical rain forests in the Andaman and Nicobar Islands, the

Western Ghats, and the North Eastern states, to dry alpine scrubs high in the Himalayas to the north.

Between the two extremes, the country has semi-evergreen rain forests, deciduous monsoon forests, and

thorn forests, subtropical pine forests in the lower mountain zones and temperate mountain forests.

Sixteen major forests types are recognized, subdivided into 221 minor types.

Marine Environment

The coastal waters of India are extremely rich fishing grounds. Coral reefs occur along a few sections of

the mainland, principally the Gulf of Kutch, off the southern mainland coast, and around a number of

Islands opposite Sri Lanka. This general absence is due largely to the presence of major river systems and

the sedimentary regime on the continental shelf. Elsewhere, corals are also found in Andaman Nicobar

and Lakshadweep Island groups although their diversity is reported to be lower than in south-east India.

Value of Biodiversity

1. Survival

Without biological diversity, we would perish. Biodiversity meets the basic survival needs of

a vast number of people. In most communities the livelihood of the people revolves around the

Zoogeographical regions of India

Region Description

Himalayan region The wild life wealth here consist of Yak,

Gural, snow – leopard, kasturi deer Etc.

Malabar region The climate here is moderate.

VariousKinds of Monkeys, deer, etc. are

foundhere

Nilgiri region This region is extremely rich in Varieties of

birds. Elephants are also Found here.

Lions are found very rarely

Northern plains The animals found in this region are

elephants, leopards, Neelgai, jackal,deer,

etc.

Desert land Deer, cheetal, sambhar, neelgai, Snakes,

lizards, etc. are abundantly found in this

area.

Deccan plateau Animals mainly found in this region are

Elephants, lions, tigers, monkeys, deer and

Some varieties of snakes.




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biodiversity of the area. For instance, in the forest belt of Ghana most men are hunters. These

hunters survive on the availability of antelopes, rabbits, snails, etc.

2. Health and healing

Even today, a large number traditional communities depend on traditional medicine for

primary health care, most of which are derived from plants and animals. Approximately 25%

of all prescription drugs are derived from plants.

3. Food Security

Biodiversity is critical for agriculture. All our food is derived from the biological world. Wheat,

potatoes, vegetables, fruits, milk, meat, honey etc are the outcomes of Biodiversity. Many plants

species such as asafetida, ginger, mint, turmeric etc are used as spices all over the world.

Biodiversity is also a source of new crops of improved variety and of bio-degradable pesticides.

4. Productive Value

Biodiversity also has a productive value. There are many products used by human which are

derived from natural sources. Cinchona plant is used to make medicines, and wood is used as

fuel. Production of charcoal is through plants and trees. A number of dyes and dye based

products are also obtained from plants.

5. Ethical Value

Each species is unique and has the rights to exist. Human do not have the right to eliminate any

species. Scientific and ethical principle should guide developmental activities. Ethical use of

natural elements has deep roots within human culture, religion, and society. A sustainable world

requires an ethics that is ultimately incorporated into culture and is long lasting.

6. Aesthetic pleasure

Biodiversity also has great aesthetic value. Each species and ecosystem adds to the richness and

beauty of life on earth. Perhaps no medium can match the sheer joy of watching a sunset over an

ocean, the sight of a leaping deer, the sounds of singing bird, or the smell of wet earth after the

first rains. Other examples of aesthetic rewards include eco-tourism, Ornithology, wild life,

keeping pets, gardening etc.

7. Ecological Services

Species evolve to fill particular niches in an ecosystem or habitat. Many species also depend on

each other in intricate ways of survival. Destroying one species can lead to further extinction or

changes. Specific life forms present in a particular habitat help to create conditions for other life

forms to live. For example, a single tree provides not only it’s products, which may have economic value, but it is also a habitat for innumerable living things. In addition, it also plays a

vital role in conserving soil and water and helping to keep the air clean, nutrient cycling and

climate regulation. In one study, published in 1997, in the science journal Nature, researchers

estimated the value of these ecosystem services at between $ 16 Trillion and $ 54 Trillion a year.

Biodiversity at Global Level

It is estimated that there exists 5-30 million species of living forms on our earth. Of these, only

1.5 million have been identified. These include 300,000 species of green plants and fungi,




25

800,000 species of insects, 40,000 species of vertebrates, and 360,000 of microorganisms.

According to some recent estimates; the number of insects alone may be as high as 10 million, but many

believe it is more likely to be around 5 million.

The tropical forests are regarded as the richest in biodiversity. Scientists are of the opinion that whatever

be the absolute number, more than half of the species on the earth live in moist tropical forests which is

only 7% of the total land surface. Insects (80%) and primates (90%) make up most of the species. For

instance, from a single tropical leguminous tree 43 ant species belonging to 26 genera have been

retrieved. This approximately equals the ant diversity of all the British Isles. In 10 selected one hectare

plots in Kalimanathan in Indonesia, Peter S.Aston of the Harvard University found more than 700 species,

are almost equal to the number of tree species native to all of North America.

The following explanations have been put forward with regard to the high species diversity in tropics:

1. In tropics, conditions for evolution were optimum and for extinction fewer;

2. In tropics, species diversity was conserved over geological time. This is because low rates of

extinction prevailing there; and

3. Biological diversity is the result of interaction between climate, organisms, topography, parent

soil materials, time and the heredity. The tropics are the ideal place for such an interaction.

Biodiversity at Country Level

The Indian region geographical area of 329 million hectares is quite rich in biodiversity with a

sizable percentage of endemic flora and fauna. This richness in biodiversity is due to immense variety of

climatic and altitudinal conditions coupled with varied ecological habitats. These vary from the humid

tropical Western Ghats to the hot desert of Rajasthan from the cold desert of Ladakh and the icy mountain

of Himalayas to the warm costs of peninsular India.

The country has over 115,000 species of plants and animals already identified and described. In

addition, the country is very important Vavilovian Center of biodiversity and origin of over 167 important

cultivated plant species, and some domesticated animals.

In fact, our country has been recognizing as one of the world’s top 12 mega diversity nations. In flora, the country can boast of 45,000 species which accounts for 15 percent of the known world

plants.

Of the 15,000 species of flowering plants, 35 percent are endemic and located in 26 endemic centers.

Among the monocotyledons, out of 588 genera occurring in the country, 22 are strictly endemic.

The family Poaceae has the highest endemism both by genera and species.

The North Eastern region could boast of being unique treasure house of orchids in the country, the

abode of about 675 species out of 1,000 available in the Indian peninsula and against 17,000 species the

world over. The important Indian orchids are: Paphiopedilum fairieyamum (Lindl) pfitz., Cymbidium

aloiflium Sw., Aerides crispum Lindl., etc.

Our country is very rich in faunal wealth also. The country has nearly 75,000 animal species, about 80

percent of which are insects.

In animals, the rate of endemism in reptiles is 33% and in amphibians 62%. Further there is wide

diversity in domestic animals, such as buffaloes, goats, sheep, pigs, poultry, horses, camels and yaks.

Domesticated animals too have come from the same cradles of civilization as the major crops.




26

There are no clear estimates about the marine biota though the coastline is 7,000 km long with a

shelf zone of 452,460 sq km and extended economic zone of 20,13,410 sq km. There is an abundance of

seaweeds, fish, crustaceans, mollusks, corals, reptiles and mammals.

Information regarding other flora and fauna are patchy. Hundreds of new species may be present in

our country-awaiting discovery. The Western Ghats in Peninsular India, which extend in the southern

states, are a treasure house of species diversity. Out of the described 15,000 species of the flowering

plants in India about 5,000 species occur on the Western Ghats of Kerala; 235 are exclusive to this

region. It is estimated that almost one-third of the animal varieties found in India have taken refuge in

Western Ghats of Kerala alone.

Biodiversity at local level (Tamil Nadu)

One sixth of landmass of Tamil Nadu is covered with forests. According to State of forest report 2003 by

the Forest Survey of India, the total forest cover of the State is 22643 KM² constituting 17.41% of

geographic area. This includes 2440 KM² of very dense forest, 9567 KM² of moderately dense forest and

10636 KM² of open forest. Tamil Nadu ranks 11th among the Indian States and Union Territories with

reference to total forest cover. The recorded forest area of the state is 22,877 KM² constituting 17.59% of

the geographic area. Tamil Nadu ranks 13th among the Indian States and Union Territories with reference

to total recorded forest area.

There are 8 wildlife sanctuaries over 2, 82,685.57 ha and 12 bird sanctuaries over 17,074.59 ha, 5

National Parks over 30784.23 ha, 3 Tiger Reserves, 4 Elephant Reserves and 3 Biosphere Reserves for in

situ conservation of wild fauna and flora.

The Angiosperm diversity of India includes 17,672 species. With 5640 species, Tamil Nadu ranks 1st

among all the States in the Country. This includes 533 endemic species, 230 red-listed species, 1559

species of medicinal plants and 260 species of wild relatives of cultivated plant. The Gymnosperm

diversity of the country is 64 species of which Tamil Nadu has 4 species of indigenous Gymnosperms.

The Pteridophytes diversity of India includes 1022 species of which Tamil Nadu has about 184 species.

Tamil Nadu wild plant diversity also includes vast number of Bryophytes, Lichens, Fungi, Algae and

Bacteria.

The faunal diversity of Tamil Nadu includes 165 species of fresh water Pisces, 76 species of Amphibians,

177 species of reptiles, 454 species of birds and 187 species of mammals. According to the CAMP reports

the red-listed species include 126 species of Pisces, 56 species of Amphibians, 77 species of reptiles, 32

species of birds and 40 species of mammals. The endemic fauna includes 36 species of Amphibians, 63

species of reptiles, 17 species of birds and 24 species of mammals

India as a Megadiversity Nation

The mega diverse countries are a group of countries that harbor the majority of the earth species

and are therefore considered extremely biodiverse.

World Conservation Monitoring Centre identified the 17 mega diversity countries are: Australia, Brazil,

China, Colombia, Democratic Republic of the Congo, Ecuador, India, Indonesia, Madagascar, Malaysia,

Mexico, Papua, New Guinea, Peru, Philippines, South Africa, United States and Venezuela.

India is one the megadiverse nation of Asia. It is highly diverse having all the natural resources

required for all kinds of living organisms. In addition to the vast diversity of plants and animals, our




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country is rich in cultural, geographical, and climatic diversity. The diversity in India is as follows;

Geographical diversity: India is a vast geographic region. It comprises of Himalayan region,

Ganga plains, Thar Desert, and Deccan plateau. The land form includes the plain of Ganga on one

side to highlands of Deccan plateau on other side. Thus India represent almost all kinds of

geographic variations found else where in the world.

Climatic diversity: The climatic conditions of the country range from cold temperate and frost

covered regions of Himalayas to low rainfall regions of the dry tropics in the north west of the

country. On the basis of annual rainfall, the country can be divided in to four climatic regions-

wet zone(more than 200cm),intermediate zone(100-200)cm, dry zone (50-100cm) and arid

zone(below 50cm).Hence India has almost all climatic variations found else where in the

world.

Biodiversity: From the point of view of biodiversity, India is divided into nine

phytogeographical regions. A variety of physical and climatic factors lead to the richness in

biodiversity. The country is also one of the12 primary centers of origin of cultivated plants and

domesticated animals. It is considered to be homeland of the167 important plant species of

cereals, millets, fruits, condiments, vegetables, pulses, fibre, crop and oilseeds, and 114 breeds

of domesticated animals. The country is also rich in animal biodiversity along with its rich

plant biodiversity resources.

Habitat diversity: India represents almost all types of habitats of the world. High mountains

ranges, hills, plateau, plains, deserts, etc. provide a variety of habitats for plants and animals.

Similarly a number of fresh water and saline lakes, reservoirs, ponds, rivers, streams provide

diversity of habitats for aquatic plants and animals

Cultural diversity: India is a country with a developed ancient cultivation. India’s culture has been enriched by successive waves of migration which where absorbed in to Indian way of

life. Our country possesses vast cultural diversity; from Jammu and Kashmir in the north to

Kanyakumari in the south; from West Bengal in the east to Thar Desert in the West. Rajasthan

and Madhaya Pradesh represent a wide array of tribal cultures. Diversity can also be seen in

food habits. Both vegetarian and non vegetarian food habits are common. Languages spoken in

India have also created diverse traditions of culture in India. There are a large number of

languages in India.Thus the country is rich in cultural diversity as well.

HOT SPOTS OF BIODIVERSITY:

The hotspot concept has been designed by Norman Myres in 1988 to designate priority areas for in

situ conservation. Hotspots are the richest and most threatened reservoirs of plant and animal life on

earth.

Criteria for determination of a hotspot:

Number of endemic species

Degree of threat; in terms of habitat loss

Hotspots are areas of exceptionally rich concentration of species with high endemism but at the same

time face high pressure of anthropogenic disturbances. There are 25 such hotspots all over the world.

Out of 25 two hotspots are located in India. The first hotspot in India is the Western Ghats and




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second is the hilly region of north east Himalayas up to Myanmar in the east.

ENDANGERED AND ENDEMIC SPECIES:

At present the population of all plants and animals are declining rapidly and numbers of species are

already on the verge of extinction. Such plants and animals species are called endangered species. The

world conservation union has recognized eight red list categories of species; extinct; extinct in the

wild; critically endangered; endangered; vulnerable; lower risk; data deficient and not Evaluated. The

red data book, published in two volumes, lists about 25,000 endangered species from across the world.

Flying squirrel, Gir lion, crocodile, flamingo,wild ass, etc. are some endangered animal species of

India. Commiphora weightii(guggal), Ravolfia serpentine (sarpgandha), Santalum album (sandal),

Adansonia digitata(kalpvrisha), Tecomella undulata(rohida),etc are some of the endangered plant

species of India.

The plant or animal species confined to a particular region and having originated there or species

which occur continuously in that area are known as endemism. Eletaria repens, ficus religiosa, butea

monosperma,ficus benagalensis,etc some of the endemic plants of India.

THREATS TO BIODIVERSITY

1. Unplanned development and habitat destruction

When people cut down trees, fill a wetland, plough grasslands or burn a forest, the natural habitat

of a species is changed or destroyed. Large scale development projects such as industrial plants or

hydroelectric projects have contributed substantially to the loss of biodiversity rich areas. Projects such as

construction of large dams not only result in submergence of large tracts of forests but also introduce

human settlements and roads within forest areas.

2. Poaching and overexploitation for commercial gain:

Many plants and animals have been over exploited by humans, sometimes to the point of

extinction. Many species such as tigers and elephants are killed or poached for their skin, tusks, claws,

etc. which have high commercial value. Others, such as several snake and bird species are caught and

smuggled out for their value for collectors and as pets. A rapidly expanding pharmaceutical industry, for

which no collections regulations exist, also affects medicinal plants.

3. Environmental pollution:

Soil, water and air pollution affects the functioning of ecosystems and may reduce or eliminate

sensitive species. For example, the decline of fish eating birds and falcons due to pesticide pollution. Lead

poisoning is major cause of mortality of many species such as ducks and swans and cranes. In India,

industrial effluents are destroying coral reefs and other marine life.

4. Global climate change:

In the coming years, climatic change could also affect global biodiversity. Many species which

cannot adjust to the warmer climatic conditions could become extinct. A change in the climatic conditions

may also result in the characteristics of habitats, there by affecting the species within those habitats. Some

habitats such as islands and coastal systems, which are at risk of flooding and submergence due to rising

sea levels, could suffer heavily, particularly high losses of biodiversity.

5. Invasion by introduced species:




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The introduction of non native species deliberately or accidently has been a major threat to

biological diversity worldwide. The introduced animals and plants pose a threat to local species of fauna

and flora for eg: Lantana camera originally introduced as the ornamental plant from Brazil is spreading

rapidly in our forests at the expense of local species. Water hyacinth clogs rivers and threatens the

survival of many aquatic species in the several tropical countries, including India.

6. Nature of legal systems:

In planning legal enforcements, a perfect combination of economic realities and involvement of

the people is required. Protection for wildlife in India is negligent. Parks do not have enough rangers

to keep out poachers and villagers are often allowed to live within sanctuaries, which leads to growing

conflicts between the local populations and animals particularly tigers.

7. Mining:

Every mining activity involves digging up tones of earth in orders to get to the ore. In the process

it leads to deforestation and consequently, the biodiversity of the particular place is threatened.

Moreover, the streams are polluted with dangerous chemicals.

8. Exploitation of water resources:

Over exploitation of surface water creates water scarcity in the absence of rainfall and the water

pollution harms the aquatic diversity and ultimately threatens its survival.

9. Forest life:

Fire plays an important role in the forest ecosystems. Common causes include lightning, human

carelessness, volcanic eruption, etc. Fires in forest due to natural or manmade reasons harm the insects,

birds, and wild animals.

10. Eutrophication

Over the past four decades, nutrient loading has emerged as one of the most important factors of

biodiversity loss in terrestrial, fresh water, and coastal ecosystem. Excessive nutrient enrichment of water

bodies stimulates the growth of algae and lowers oxygen production. It leads to the death of fish and other

aquatic organisms.

11. Waste disposal:

Dumping of nuclear and radioactive waste on land or water kills the plant and animal

species leading to their extinction.

12. Other factors:

Other ecological factors that may also contribute to the extinction of plant and animal species are

as follows;

Distribution range: The smaller the range of distribution, the greater the threat of

extinction.

Degree of specialization: The more specialized an organism is, the more vulnerable it is to

extinction.

Position of organism in food chain: The higher the organism is in food chain, the more

susceptible it becomes.




30

Reproductive rate: Large organisms tend to produce fewer off springs at widely spaced

intervals.

CONSERVATION OF BIODIVERSITY:

Everyday, around the globe, species are being lost and others are being pushed towards extinction.

This threatened biodiversity needs to be conserved. Biodiversity conservation is scientific management at

its optimum level and derives sustainable benefits for both the present and the future

In situ conservation:

In situ means the natural or the original place. In this method, the plants and animals are

conserved in their natural habitats.

National Parks:

A national park conserves the environment and the wild life therein. National parks are

areas dedicated to conserve wild animals and natural environment. All private rights are non-existent

and all forestry operation and others usages such as grazing of domestic animals are prohibited in

these areas. Conservation of species of a habitat with minimal or very low intensity of human activity

occurs in a natural park. No one apart from the public servant on the duty and permitted persons by

chief wildlife warden resides in the park. In India, there are 90 national parks.

Wild life sanctuary:

A wild life sanctuary is dedicated to protect wild life, but it considers the conservation of species

only and its boundary is not limited by the state legislation. Hunting without permit is prohibited and

grazing and movement of cattle is regulated in sanctuaries and absolutely prohibited in Natural Park

which is established in or outside a sanctuary. In a sanctuary, human activities are allowed but in

national park human interference are totally prohibited. Conservation of species and habitats occurs by

manipulative management. No person resides in the park other than the public servant on duty and

permitted persons by the chief wild life wardens. It comprises of core, buffer and restoration zones. In

India, there are 492 wild life sanctuaries.

Biosphere reserve:

Biosphere reserves have been described as undisturbed natural areas for scientific study as well as

areas in which conditions of disturbances are under control. They have been set aside for ecological

research and habitat preservation. Conservation of natural resources and improvement of the

relationship between man and environment is the chief objective of biosphere reserves. In India 13

biosphere reserves have been established. A biosphere reserve consists of core, buffer, restoration and

cultural (transition) zones. The core zone comprises of an undisturbed and legally protected

ecosystem. The buffer zone surrounds the core area and is dedicated to research and educational

activities. The transition zone is the outermost part of the biosphere reverse where activities like

settlements, agriculture, forestry and recreational activities occur in harmony with conservation goals.

The in situ conservation application is advantages in many respects, but also has certain limitations.




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The advantages of in situ conservation are:

Long term protection

Natural ecosystems spread in large areas provide a good opportunity for conservation as well as

evolution

Cheaper means to protect the species

The limitations of in situ conservation are:

Proper protection against environment pollution may not be enough in natural ecosystems.

Ex situ conservation

In this technique, plant and animal species are conserved their natural habitats. Ex situ

conservation is the chief mode of preservation of genetic resource. This can be done through

establishment of gene banks, zoos, botanical gardens, culture collections etc

Gene banks

Gene banks also known as germplasm banks are established for ex situ conservation. Here seeds,

pollen grains, vegetative propagating parts of various endangered plants can be preserved in viable

conditions. The result of storing seeds under frozen conditions is to slow down the rate at which they lose

their ability to germinate. Seeds of crop plants such as maize and barely could probably survive thousand

of years in such conditions. A range of crops like millets, oil seeds, vegetables, turnip can be maintained

for several years in liquid nitrogen without any decline in viability.

Botanical gardens:

Rare and endangered plant species are conserved in botanical gardens. In addition to conservation

in botanical gardens, they are also used for the purpose of study and research of specific plant characters

and for disseminating scientific information and experience to promote sustainable development

Aquaria

The aquaria are mainly for captive propagation of threatened or endangered fresh water species. It

also finds its role in the educational facilities. However, now it is assuming new importance in captive

breeding programmes. The world conservation Union is currently developing captive breeding

programmes for endangered fish.

Tissue culture technique:

Tissue culture is a special type of asexual propagation where a small piece of shoot apex, leaf

section, or even an individual cell is cut out and placed in sterile culture container containing a special

culture medium. The culture medium contains a gel with the proper mixture of nutrients etc which causes

the plant to grow at very rapid rates to produce new plantlets. A very specialized laboratory is required for

tissue culture. The tissue culture is used for rapid multiplication of plants.

DNA technology

In this technique, the whole DNA of a plant or animal is conserved or a part of it is conserved.

Through the use of recombinant DNA, genes that are important can be isolated and used in other species

or applications, where they may be some from of genetic illness or discrepancy and provide a different

approach to biodiversity conservation

Cryo preservation:




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In vitro conservation in liquid nitrogen at that temperature of -196oC is quite useful for

conservation of vegetatively propagated plants.

Advantages

Long term conservation

Due to controlled supervision ,assured food ,shelter and security the species can survive

longer and may breed more offspring than they usually can

The quality of offspring may be improved by genetic techniques

Breeding of hybrid species is possible.

The limitations of ex situ conservation:

Not a viable option for protection of rare species due to human interference

Can be adopted for only a few kinds of species

Overprotection may result in loss of natural properties

Steps to Preserve Biodiversity:

No undisturbed land be used for setting industries or other developmental works, because

it leads to loss biodiversity

Population growth should be controlled

Measures should be taken to reduce environmental pollution

Effective measures for conservation of biodiversity be developed and strengthened in all

countries

Germplasm for existing species should be collected




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UNIT – II

ENVIRONMENTAL POLLUTION Pollution is any addition to air, water, soil or food that threatens the health, survival or activities of humans or other living organisms. Pollutants can enter the environment naturally or through human activities. Pollutants come from two types of sources.

1. Point sources of pollutants are single, identifiable source. E.g. drain pipe of a factory.

2. Non point sources of pollutants are dispersed and often difficult to identify.

Harmful Effects of Pollutants:

Unwanted effects of pollutants include 1. Disruption of life support systems for humans and other species.

2. Damage to wild life, human health, property

3. Nuisance such as noise and unpleasant smells taste and sight.

Solution to pollution:

Two basic approaches to deal with pollution

1. Pollution prevention or input pollution control, which reduces or eliminates the production of

pollutants

2. Pollution clean up or output pollution control, which involves cleaning up or diluting pollutants

after they have been produced.

Reasons for pollution

1. Population explosion

2. Unplanned urbanization

3. Deforestation

4. Excessive heat, noise, light or radiation from the industrial area.

AIR POLLUTION

Air Pollution is the presence of one or more chemicals in the atmosphere in sufficient quantities

and duration to cause harm to us, other forms of life and materials or to alter climate.

Types of Air Pollutants:

1. Primary air pollutants : emitted directly in the troposphere

2. Secondary air pollutants: Some primary pollutants may react with one another to form new

pollutants.

Major air pollutants found in the atmosphere are: CO, NO2, SO2 SPM, O3, Lead.

Carbon mono oxide (CO): colorless, odorless gas that is poisonous to air breathing animals. Source: Incomplete combustion, Cigarette smoking, motor vehicle exhaust Health effects:

1. Reacts with hemoglobin in RBC and reduces the ability of blood to bring O2 to body cells and

tissues.

2. Aggravates chronic bronchitis, emphysema, and anemia.

3. At high level cause coma and death.

Nitrogen di oxide (NO2): Reddish brown irritating gas that gives photo chemical smog its brownish

colour.




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Source: Motor Vehicle, power and industrial plants

Health Effects: Lung irritation and damage, aggravates asthma and chronic bronchitis

Environmental effects: Reduces visibility. HNO3 damage soil, trees and aquatic life in lakes.

Property damage: Corrode metals; eat away stone, statues and monuments.

Sulphur di oxide (SO2): Colorless irritating gas.

Source: Coal burning power plastics

Health effects: Breathing problem, chronic exposure leads to bronchitis

Environmental effects: Reduces visibility, acid deposition

Property damage: Can corrode metals; eat away stone and statues. Damages paint, paper, and leather.

Suspended particulate matter (SPM): Variety of particles and droplets.

Sources: burning fossil fuel, vehicle, agriculture, and construction unpaved roads.

Health Effects: Nose and throat irritation, lung damage and bronchitis.

Environmental effects: Reduces visibility, acid deposition

Property Damage: Corrodes metals Soils, and discolor buildings, clothes fabric and paints.

Ozone (O3): Highly irritating gas with an unpleasant odor that forms in the troposphere as photochemical

smog.

Sources: Chemical reaction with volatile organic compounds and NO2.

Health effects: Breathing problems, coughing, eye, nose and throat irritation, aggravates, asthma,

bronchitis emphysema.

Environmental Effects: Damage plants, trees, reduce visibility

Property Damage: Damages rubber, fabrics and paints.

Lead: Solid toxic metal and its compounds emitted into the atmosphere as particulate matter.

Sources: Paint, Smatters, lead manufacture, storage batteries leaded gasoline.

Health effects: Accumulates in the body, brain and other nervous system and damage brain and cause

mental retardation, cancer, digestive problem.

Environmental Effect: harm wild life.

Photochemical smog: (Brown Air Smog)

A photochemical reaction is any chemical reaction activated by light. Air pollution known as

photochemical smog is a mixture of more than 100 primary and secondary pollutants formed under the

influence of sunlight.

Industrial Smog: (Gray – Air Smog)

During winter people in such cities were exposed to industrial smog consisting mostly of SO2,

suspended droplets of H2SO4 and a variety of suspended solid particles and droplets called aerosols.

Indoor Air pollution:

According to EPA studies, 11 Common pollutants generally are two to five times higher inside

homes and commercial buildings.

The four most dangerous indoor air pollutants are cigarette smoke, formaldehyde,

Radioactive radon and very small fine and Ultra fine particles.




35

S.No

.

Substance Indoor

Pollutants

Source Possible Threat

1 Chloroform Chlorine treated water with hot

showers

Cancer

2 Para dichlorobenzene Air freshner, naphtha ball crystals Cancer

3 Tetrachloride ethylene Dry cleaning fluid fumes on clothes Nerve disorders, damage to

liver and kidneys, possible

cancer

4 Formaldehyde Furniture stuffing, paneling, foam

insulation

Irritation of eyes, throat

skin, lungs nausea,

dizziness

5 Benzo α Pyrenes Tobacco, wood stove Lung Cancer

6 Styrene Carpets, Plastic products Kidney, liver damage

7 CO Faculty furnace, unvented gas

stoves, kerosene, heaters

Headaches, Drowsiness,

death.

8 Methylene chloride Paint strippers, thinners Nerve disorders, diabetes.

9 Radon-222 Radioactive soil, rock surrounding

foundation

Lung Cancer

10 Asbestos Pipe insulation, Vinyl ceiling and

floor titles

Lung disease, cancer

11 Nitrogen Oxides Unvented gas stove, wood stove Irritated lungs, children’s cold.

12 1,1,1

Trichloroethylene

Aerosol sprays Dizziness, irregular

breathing

Effects of Air pollution: 1. Cause asthma, acute shortness of breath, lung cancer, chronic bronchitis, emphysema.

2. According to WHO at least 3 million people die prematurely each year from the effects of air

pollution.

3. Affects plants because of soil nutrient depletion, and increased susceptibility to pests, disease

fungi and drought.

4. Air pollutants cause billion of dollars in damage to various materials we use.

Damage marble statue

Damage historic buildings

Stained glass, pitted, gouged, discolored.




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Break down paint on car and houses

Deteriorate roofing material

5. Acid rain

6. Destroys ozone layer depletion.

7. Global warming.

8. Photochemical smog

Control measures:

1. Source Correction:

The root cause of pollutant will be reduced by incorporating certain changes in the production process of an industry or by changing the raw material. E.g. using lead free petrol

2. Control methods:

By incorporating suitable control equipments E.g. ESP, Cyclone, Scrubbers.

3. Enforcing laws / policies:

Air Act should be followed strictly to reduce air pollution. The Kyoto and Montreal protocol should be strictly followed by all the nations. International co-operation is very much essential to reduce green house gas emission.

4. utilization of alternate energy

To reduce air pollution, Instead of using petrol, diesel and coal for energy generation, it is necessary to switch over for renewable energy sources like solar kind and biomass energy.

WATER POLLUTION Water pollution is any chemicals, biological or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses. Water Quality:-

1. Measuring the number of colonies of coliform bacteria present in a water sample.

WHO recommends zero colonies / 100ml for drinking water. US, EPA recommends maximum level for swimming water of 200Colonies /100ml. 2. Water pollution from Oxygen demanding wastes and from plant Nutrients can be determined by measuring the level of dissolved oxygen

3. To measure the BOD biological Oxygen demand to determine the Quantity of oxygen demanding wastes in water. 4. Chemical analysis is widely used to determine the presence and concentration of inorganic and organic chemicals that pollute water.

5. Living organisms as indicator species to monitor water pollution. Point sources: - Discharge pollutants at specific location through pipes, ditches or sewers into bodies of surface water. Non point sources: - Cannot be traced to any single site of discharge. They are usually large land areas or air sheds that pollute water by runoff, subsurface flow or deposition from the atmosphere. Sources

Sewage that includes organic matter, animal and human excreta-one of the major pollutants of water in the urban and rural areas is the sewage. The sewage most often contains the organic matter that encourages the growth of microorganisms. These organisms besides spreading diseases also consume the oxygen present in water. This is called oxygen depletion. The aquatic organisms like the fish




37

cannot then survive in such waters. This creates an imbalance in the aquatic ecosystems. Industries

The industries are mostly situated along the riverbanks for easy availability of water and also disposal of the wastes. But these wastes include various acids, alkalis, dyes and other chemicals. They change the pH of water. There are also detergents that create a mass of white foam in the river waters. The industrial wastes include toxic metals like lead, mercury, cadmium, etc, and other chemicals like the fluorides, ammonia, etc. Certain industries such as power plants, refineries, nuclear reactors release a lot of hot water from their cooling plants. This hot water is let into the water bodies without the temperature being reduced. This results in heating up of the water and thereby killing the aquatic life. The oxygen content of water also becomes less due to increase in the temperature. This is called thermal pollution. Agriculture

Modern methods of agriculture have resulted in use of fertilizers and pesticides to increase the yield of the crops. These chemicals enter into the water bodies with the rain water flow and the ground water by seepage. The chemicals remain in the environment for a long time and can enter the food chain. They cause a number of problems in the animals. Oil

Oil spill is a major problem in the oceans and seas. The oil tankers and offshore petroleum refineries cause oil leakage into the waters. This pollutes the waters.

Pollutant Source/Cause Effect

Sewage that includes domestic wastes, hospital wastes, excreta, etc.

Sewarage of rural and urban areas.

Oxygen depletion Spread of diseases/ epidemics

Metals-Mercury Industnal wastes

Minamata disease (resulted from the contaminated waters of the Minamata bay in Japan in 1953) - causes numbness of limbs, lips and tongue, blurred vision, deafness and mental derangement.

Lead Industrial wastes Absorbed into blood and affects PBCs, liver, kidney, bone, brain and the penpheral nervous system. Lead poisoning can even lead to coma.

Cadmium Cadmium industnes, fertilisers

Deposited in organs like the kidney, pancreas, liver, intestinal mucosa, etc. Cadmium poisoning causes headache, vomiting, bronchial pneumonia, kidney necrosis, etc.

Arsenic Fertilisers Arsenic poisoning causes renal failure and death, It can cause nerve disorder, kidney and liver disorders, muscular atrophy, etc.

Agrochemicals like DDT Pesticides Accumulates in the bodies of fishes, birds, mammals including man. Adversely affects the nervous system, fertility. Causes thinning of egg shells in birds.

Pollution of freshwater steams, lakes and Groundwater:- Flowing streams, including large ones called rivers can recover rapidly from degradable oxygen demanding wastes and excess heat through a combination of dilution and bacterial decay.




38

Clean zone – Decomposition zone – Septic zone – Recovery zone In lakes and reservoirs, dilution of pollutants often is less effective than in streams for reasons.

First, lakes and reservoirs often contain stratified layers that undergo little vertical mixing and second, they have little flow. Consequently, lakes and reservoirs are more vulnerable than streams to contamination. These contaminants can kill bottom life and fish and birds that feed on aquatic organisms.

Eutrophication is the name given to the natural nutrient enrichment of lakes. Cultural Eutrophication - Near urban or agricultural areas, human activities can greatly accelerate

the input of plant nutrients to a lake, which results in a process known as cultural Eutrophication. Ground water pollution comes from numerous sources. People who dump or spill gasoline, oil

and paint thinners and other organic solvents onto the ground also contaminates water. When groundwater contaminated it cannot cleanse itself of degradable wastes as flowing surface water does Ground water flows slowly that contaminants are not diluted and disposed effectively.

Arsenic pollution causes various abnormalities causing skin lesion like leprosy. Nitrate when present in excess in drinking water causes blue baby syndromes or

methaemoglobinemia. The disease develops when a part of heamoglobin is converted into non functional oxidized form.

Excess of fluoride in drinking water causes defects in teeth and bones called floozies. Effects of water Pollution:-

Oxygen demanding wastes deplete dissolved oxygen in the water body which may be harmful to

animals.

Eutrophication also results in overgrowth of plants like Eicchornia that covers the entire surface of

water. This reduces the light reaching the lower layers in water. Thus, enrichment of water with

inorganic nutrients like nitrates and phosphates is called eutrophication.

Pollutants accumulate in the organisms and cause serious health problems. The contamination of

water with these pollutants results in their entry into the microscopic plants and animals. These

organisms are fed upon by higher aquatic life like the fish. The fish in turn are fed upon by the

land animals including man.Thus, the pollutant reaches the body of man. At each step in the food

chain, the contaminant increases in quantity. This is because a fish feeds on large quantity of

smaller plants and man eats fish. These contaminants like DDT remain in the fats and are not

degraded in the body. Over the years the amount of DDT increases in the body. This is called

biomagnification.

Oxygen depletion and cause Eutrophication.

Waste water contain many pathogen & viruses, Water borne disease such as cholera, dysentery,

typhoid, jaundice etc are spread by water contaminated with sewage.




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Pollutants such as pesticides are non biodegradable and accumulate in the food chain known as

Biomagnifications / bioaccumulation

Pollution of water by organic wastes is a major cause for occurrence of epidemics like cholera,

gastroenteritis in India. In fact, a good indication of pollution of water is the presence of bacteria

E. coli that lives in the human intestines.

Nitrogen & phosphorus helps in the growth of algae which when die and decay consume oxygen

of water. Under anaerobic condition foul smelling gas is produced. Changes in pH, O2,

temperature will change many physico – chemical characteristics of water.

Toxic substances polluting the water ultimately affect human health. Some heavy metals like Pb,

Hg, Cd cause various types of diseases.

Minamata diseases:- Numbness of body parts, vision and hearing problem, abnormal mental

behavior occurred due to consumption of methyl mercury contaminated fish

Itai – itai disease caused by cadmium contaminated rice. Bones, liver, kidney, lungs, pancreas

and thyroid are affected.

Control of water pollution

1. Prevent Ground water contamination.

2. Greatly reduce non point runoff

3. Reuse treated waste water for irrigation

4. Find substitutes for toxic pollutants.

5. Work with nature to treat savage.

6. Practice four R’s of resource use (Refuse, Reduce Reuse, Recycle). 7. Reduce resource waste

8. Reduce birth rates.

9. Use Nitrogen fixing plants to supplement the use of fertilizers.

10. Adopting Integrated pest management to reduce reliance on pesticides.

11. Planting trees would reduce pollution by sediments.

12. For controlling water pollution from point sources, treatment of waste water is essential.

13. Waste water should be properly treated by primary and secondary treatments to reduce the

BOD, COD levels to the Permissible levels.

14. Advanced treatment for removal of nitrates & phosphate.

15. Proper Chlorination should be done to prevent the formation of chlorinated hydrocarbons or

disinfection should be done by ozone or UV.

Sewage Treatment

The sewage before being let into the water bodies must be purified. This is done in three steps as follows:

Primary treatment

Secondary treatment

Tertiary treatment

Effluent treatment

Primary Treatment

The water is sieved through coarse sieves and made to stand in sedimentation tanks. This makes the




40

heavy suspended matter settle down. It is then passed through a bed of rocks. Secondary Treatment

The organic materials that are biodegradable are treated with the help of decomposers and oxygen. Then, the water is also chlorinated to remove the germs. Tertiary Treatment

This step removes the inorganic pollutants like the nitrates, phosphates, detergents, metal ions, etc. by passing the water through activated charcoal that acts as a filter. Effluent Treatment

The industrial wastes should be treated before being let into the water bodies. The toxic materials should be removed, the metallic compounds should be precipitated, the acids and alkalis should be neutralized and the temperature of the hot waters should be reduced. Public Awareness

The public should be made aware of the dangers of water pollution. This will ensure that the water bodies are not contaminated and are maintained clean

It can take 100-1000 years for contaminated ground water to cleanse itself of degradable wastes. SOIL POLLUTION

Degradation of soil and land due to industrial, agricultural and by other human activities is called soil or land Pollution. Sources

1) Industrial wastes

2) Urban waste

3) Radio active pollutants

4) Agriculture practice

5) Chemical & metallic pollutants

6) Biological agents

7) Mining

8) Resistant objects.

1) Industrial waste

- Fly ash from stone quarries, thermal power plant, cement factories.

- Cement & steel industries disturb the salt balance and destroy the fertility

- Textile and dyeing industries effluents affect the soil property.

- Chrome tanning involves huge quantities of chemicals which are very harmful to soil.

- Sludge of Industrial waste contain toxic heavy metals and pollute the soil.

2) Urban Waste:-

It comprises both commercial and domestic waste. - Solid waste and refuse contribute to soil pollution.

- Plastic bags prevent the growth of plants, it kill animals it contain harmful chemicals &

dyes.

- Urbanization produce enormous solid waste which leads to soil pollution.

3) Radioactive Pollutant:-

Radioactive substances resulting from explosive and radioactive waste, penetrate the soil and accumulate there creating soil / land pollution.




41

4) Agricultural practices:-

Using various pesticides, fertilizers, herbicides fungicides, weedicides and soil conditioning agents the crop yield has been increased, but these chemical pollute the soil and also clears the fertility of the soil.

5) Biological agents:- Soil gets large quantities of human, animals, and birds excreta which constitute the major source of land pollution by biological agent. Biomedical waste poses great threat to the soil conditions.

6) Mining: - Mining & ore processing activities spoil the land.

7) Resistant objects:-

Large resistant objects such as can, plastic, tyres, glasses, used vehicle, refrigerator etc dumped in to nature; destroy the beauty of the landscape

8) Changing forest into agricultural lands.

9) Laying roads change the stability of slope & hydrological system in the hilly region.

Effects of soil pollution:- - Sewage and industrial effluents which pollute the soil, ultimately affect human health.

- Various types of chemicals, acid, alkali pesticides, fertilizer, heavy metals affect soil

fertility by causing changes in physical, chemical and biological properties.

- Some persistent toxic chemicals inhibit the non-target organism, soil flora and fauna and

reduce soil productivity.

- Sewage sludge has many pathogenic bacteria, viruses, and intestinal worms which may

cause various types of diseases.

- Decomposing organic matter in soil also produces toxic vapours

- Radioactive fallout on vegetation is the source of radio isotopes which enter the food chain

in grazing animals.

Some of this radio isotopes replace essential elements in the body and cause abnormalities. - Chemicals or their degradation products from soil may percolate and contaminate ground

water resources.

- Applications of the pesticides also affect the micro-organism living in the soil.

- Because of soil pollution, the pH of the soil is changed and affects the Crop yield.

- It changes the porosity of the soil and affects the infiltration, water storage of the region.

- Pesticides, some heavy toxic metals & chemicals, are known to cause migraine, dizziness,

stomach and abdominal cramps.

- In long run, accumulation of toxins inside the body can cause cancer, reduce fertility and

immunity.

Control measures:-

1. Effluents should be properly treated before discharging them on soil.

2. Solid waste should be properly collected and disposed off by appropriate method.

3. From the wastes, recovery of useful products should be done.

4. Biodegradable waste should be used for generation of biogas.

5. Cattle dung should be used for CH4 generation.

6. Microbial degradation of degradable substances also reduces soil pollution.

7. Agro forestry programme for reclaiming degraded land soil is needed.




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8. Integrated pest management.

9. Organic farming.

10. Biomedical waste treatment facilities like incinerator, autoclave, microwave systems should be

installed in hospital & medical institutions.

Marine Pollution

- Oceans are the ultimate sinks for much of the waste matter we produce.

- Oceans can dilute, disperse and degrade large amounts of raw sewage, sewage sludge, oil

and some types of degradable industrial wastes, especially in deep water areas.

Sources and Effect of Pollutants on Coastal Areas:-

- Areas along coast – especially wetlands and estuaries, coral reefs and mangrove swamps

bear the brunt of our enormous inputs of pollutants and wastes into the ocean.

- In most coastal developing countries, municipal sewage and industrial wastes are dumped

into the sea without treatment. This causes widespread beach pollution and Shellfish

contamination.

- Recent studies of coastal water have found vast colonics of human viruses from raw

sewage, effluents from sewage treatment plant and leaking septic tanks.

- Some people using polluted coastal beaches develop ear infections, sore throats, eye

infection, respiratory disease or gastro intestinal disease.

- Runoff of sewage and agricultural wastes into coastal water and acid deposition from the

atmosphere introduce large quantities of Nitrate & phosphate plant nutrient which cause

explosive growth of harmful algae.

- These harmful algae blooms are called red, brown or green tides, depending on their color.

- They can release waterborne and air borne toxin that can damage fisheries and kill fish

eating birds, reduce tourism and poison sea food.

Effects of Oil on Ocean ecosystem:-

- Crude petroleum or refined petroleum is accidentally or deliberately released into the

environment from a number of sources.

Sources:

- Tanker accidents and blowout at offshore drilling rigs release oil to the ocean.

- More oil is released to the ocean during normal operation of offshore wells, from washing

oil tankers, releasing the oily water, from oil pipe line and storage tank leaks.

- Natural oil seeps also release large amounts of oil into the ocean.

Effects: The effects of oil on ocean ecosystem depend on a number of factors,

1) type of oil

2) type of aquatic system

3) amount released

4) distance of release from shore

5) time of year

6) weather conditions




43

7) average water temperature

8) Ocean currents.

- Volatile organic hydrocarbons in oil immediately kill a number of aquatic organisms

especially in their vulnerable larval forms.

- Some other chemicals form tar like globs that float on the surface and coat the feathers of

birds and the fur of marine animals. This oil coat destroys their natural insulation and

buoyancy, causing many of them to drown or die of exposure from loss of body heat.

- Heavy oil component that sink to the ocean floor or wash into estuaries can smother

bottom dwelling organisms such as crab, oyster, mussels and clams or make them unfit for

human consumption.

- Some oil spills have killed coral reefs.

- Most forms of marine life recover from exposure to large amounts of crude oil within 3

years.

- But recovery from exposure to refined oil, especially in estuaries can take 10 year or

longer.

- The effects of spills in coldwater and in shallow enclosed gulfs and bays generally last

longer.

- Estuaries and salt marshes suffer the most & longest lasting damage.

Control / Prevent Marine Pollution:-

I) Toxic pollutants from industries and sewage treatment plants should not be discharged in coastal

water.

II) Run off from nonpoint sources should be prevented to reach coastal areas.

III) Sewer overflows should be prevented by having separate sewer and rain water pipes

IV) Dumping of toxic hazardous waste and sewage sludge should be banned.

V) Developmental activates on coastal areas should be minimized.

VI) Oil and grease from service stations should be processed for reuse.

VII) Oil ballast should not be dumped into sea. VII) Ecologically sensitive coastal areas should be protected by not allowing drilling.

Thermal pollution

Industries like thermal power plant, nuclear power plant etc are utilizing more water for cooling purposes. After being used, the hot water is let off into near by sea, steam and other water bodies. The hot effluent released from the above industries increases the temperature of the water body where it is discharged. Thermal pollution is the addition of excess of undesirable heat to water that makes it harmful to aquatic life and cause significant changes of normal activities of aquatic communities. Causes of thermal pollution:-

Nuclear power plants are the major pollution sources, emitting about 15% more heat per unit of electricity produced than the fossil fuel facilities. Coal fired thermal power plants are some of the other sources of thermal pollution. Municipal /Domestic sewage also raises the temperature of water bodies to some extent. The textile, paper &pulp as well as sugar industries also release hot water but to a much lesser extent.




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Effect of thermal pollution:-

1. The dissolved oxygen content of water is decreased as the solubility of oxygen in

water is decreased at high temperature

2. High temperature becomes a barrier for oxygen penetration into deep cold waters.

3. Toxicity of pesticides, detergents & chemicals in the effluent increases with increase in

temperature.

4. The composition of flora and fauna changes because the species sensitive to increased

temperature due to Thermal shock will be replaced by temperature tolerant species.

5. Metabolic activities of aquatic organisms increase at high temperature and require

more Oxygen, where as oxygen level falls under thermal pollution.

6. Discharge of heated water near the shores can disturb spawning and can even kill

young fishes.

7. Fish migration is affected due to formation of various thermal zones.

Control of Thermal Pollution:-

The following methods can be employed for control of thermal pollution. 1. Cooling Ponds: Water from condensers is stored in ponds where natural evaporation cools the

water, which can then be recirculated/ discharged in near by water.

2. Spray Ponds: The water from condensers is received in spray ponds. Here the water is

sprayed through nozzles where fine droplets are formed. Heat from these fine droplets is

dissipated to the atmosphere.

3. Cooling towers:-

1. Wet cooling tower: Hot water is sprayed over baffles. Cool air entering from sides takes away

the heat and cools the water.

2. Dry Cooling tower: The heated water flows in a system of pipe. Air is passed over these hot

pipes with fan. There is no water loss in this method.

Noise Pollution

Sound is mechanical energy from a vibrating source. A type of sound may be pleasant to some one and at the same time unpleasant to others. The unpleasant and unwanted sound is called noise. Sound is expressed in Hertz and is equal to the number of cycles per second. Decibel scale is a measure of loudness. Noise can affect human ear because of its loudness & frequency. Noise Standards recommended by CPCB committee

Area Code

Category area

NOISE level in dB(A) Leq

Day Night

A B C D

Industrial Commercial Residential Silence zone

75 65 55 50

70 55 45 40

Sources:




45

1. Various modes of transportation ( air, road, rail – transportation)

2. Industrial Operations.

3. Construction activities

4. Celebration (Social / religious function, election etc)

5. Electric home appliances.

6. Blaring loud speaker

7. Bursting of crackers.

Effects of Noise pollution:-

1. Interferes with man’s communication. 2. Noise can cause temporary or permanent hearing loss. It depends on intensity and duration of

sound level.

3. It causes high rate of accidents, general sickness, occupational, diseases, decrease in

productivity.

4. It develops annoyance, irritation and fatigue in man.

5. Causes disturbance in his work, rest sleep, communication.

6. Causes diseases like nausea, headache, insomnia, loss of appetite, peptic ulcer etc.

7. When pregnant women exposed to longer duration in noisy region. She gives birth to

defective and low weight baby.

8. It creates impaired hearing; break down of nervous system and high BP.

Control measures

1. Source reduction:

Stop the noise before it is generated. It refers applying control measures right at the noise source. Provide rubber pads on the foundation of heavy machineries, use of silencers, change the process which makes less noise.

2. Control at transmission path:

If noise is not controlled in the source, control measures like providing enclosures and barriers can be applied in the transmission path.

3. Control at the receiving end:

In some cases, the noise level cannot be reduced in the source level and transmission path. In this situation the individual protection devices like ear defenders, ear plugs, earmuffs etc. are used for human comfort.

4. Annual audio metric checkup is needed for persons working in all type of factories.

5. Planting trees and shrubs along roads in the hospitals educational institutions etc, help in reducing

noise to a considerable extent.

Nuclear hazards

Radio active substances are present in nature. They undergo natural radioactive decay in which unstable isotopes spontaneously give out fast moving particles, high energy radiations or both at a fixed rate until a new stable isotope is formed. The isotopes release energy either in the form of gamma rays or ionization particles i.e. alpha particles and beta particles. A α particles are fast moving positively changed particles whereas β particles are high speed negatively changed electrons.




46

These ionization radiations have variable penetration power; α particle is interrupted by a sheet of paper, β particle can be blocked by a piece of wood or few mm of Aluminium sheet. Ƴ rays can pass through paper & wood, but stopped by concrete wall, lead slabs or water. Source: Nuclear hazard is caused when there is the leakage of radiations from nuclear reactor,

nuclear research, laboratories and industries.

Accidents taking place in nuclear reactors.

Transportation, disposal and storage of radioactive waste also cause the nuclear hazards.

The process of mining and refining of radioactive ores also causes nuclear pollution.

Radioactive isotopes mix with atmospheric air, when nuclear tests were conducted. This

toxic substance present in the air later comes down to soil, water in the form of radioactive

rain and combine with food chain of man.

Sources of natural radioactivity include cosmic rays from outer space, radio active radon

222, soil rocks air, water and food, which contain one or more radioactive substances.

Effects of Radiations:-

- Radio active material act as environmental poison and damage the entire biota.

- Radionuclide Iodine 131 accumulate in the thyroid gland and affects the metabolic

activities and cause leukemia (cancer of bone marrow )

- Radioactive debris which settles down on the earth’s surface after a nuclear explosion is called radioactive fallout. These explosions generate large amounts of nitric oxide

molecules which react with the ozone and destroy the ozone layer.

- Neutron bomb is described as the ultimate weapon of destruction. It travels long distances

at bullet speed and kills every one in its path within a day generally in few hours.

- Genetic damage is caused by radiations which induce mutations in DNA, thereby affecting

genes & chromosomes. The damage is often seen in the off springs and may be

transmitted up to several generations.

- Somatic damage includes burns, miscarriages, eye cataract, and cancer of bone, thyroid,

breast, lungs and skin.

Control measures:- 1. To safe guard from the radiation effect, the radioactive waste should be buried deeply into the

ground or buried under the ice sheets like Antarctic or Greenland ice sheets.

2. Ban on nuclear testing

3. Nuclear plant should have proper safety measures.

4. Proper disposal of wastes from laboratory involving the use of radio isotopes should be done

Solid Waste Management

- Higher standards of living of ever increasing population have resulted in an increase in the

quantity and variety of waste generated.

- If waste generation continues indiscriminately then very soon it would be beyond

rectification.

- Management of solid waste has therefore, become very important in order to minimize the

adverse effects of solid wastes.




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- Solid waste can be classified as municipal, industrial, medical, agricultural, mining waste

and sewage sludge.

Solid waste is defined as “The material arising from human and animal activities and is being discarded as useless stuff. The solid waste may either be biodegradable or non biodegradable waste. “If the pollutants are rapidly decomposed, they are said to be biodegradable pollutants like sewage sludge. Instead, if the pollutants don’t degrade or degrade very slowly, they are said to be non-degradable pollutants like mercury and plastics.

Sources of solid wastes Wastes from homes: Contains a variety of discarded materials like polyethylene bags,

empty metal, and Aluminum cans / scrap metals, glass bottles, waste paper, diapers,

cloth/rags, food waste etc.

Waste from shop: Mainly consists of waste paper, packaging material, cans, bottles,

polyethylene bags, peanut shells, egg shells, tea leaves etc.

Biomedical waste includes anatomical waste, Pathological waste, infectious waste etc.

Construction / demolition waste include debris, rubbles wood, concrete etc.

Horticulture waste includes vegetable pails and residues.

Waste from slaughter house includes remains of slaughtered animal.

Industrial waste consists of factory rubbish, packing material, organic wastes, acid, alkali

and metals etc. During some industrial processing toxic and hazardous waste are also

produced.

Radioactive waste are generated by nuclear power plants

Thermal power plants produce fly ash in large quantities.

Effects of solid waste:-

- Solid waste released from chemical industries is usually poisonous and is very harmful.

- Biological waste and waste discarded in the form of explosive from ordnance factories are

dangerous to human life.

- The land disposed waste normally pollutes ground water and surface water.

- Some toxic wastes cause fire (if inflammable), release poisonous gases, and also even

cause explosions.

- Solid waste pollutes the water body and affects the aquatic life.

- It causes obnoxious smell and affects surrounding area.

- It affects the texture of soil and reduces its fertility.

- Solid waste acts as breeding place for mosquitoes and flies, hence, producing various

diseases.

- Causes soil sickness.

- Alters pH, porosity and permeability of soil.

Control measures:-

1. Collection and source segregation:




48

The term collection includes gathering or picking up of solid wastes from various sources. Segregation or sorting out of reusable material from the waste heap is the first step in the process of Solid waste management (SWM). The main idea is to recover useful products from the waste before dumping.

2. Open dump:-

Wastes are dumped into the outskirts of town/city. It is the most common disposing method. It is simple and less expensive but undesirable due to air and water pollution.

3. Sanitary landfill:-

Disposing of solid waste on land without creating hazards to human health and with safety is known as sanitary land fill. It is safer and more advantageous than open dump.

4. Composting:-

In this process, the decomposition and stabilization of solid wastes takes place by biochemical process under controlled conditions. Microorganisms are involved in this process. It occurs in two ways.

i) Aerobic composition – O2 is utilized to feed on organic matter

ii) Anaerobic composition – decomposition occurs in the absence of O2.

5. Pyrolysis:-

It is the process in which the waste is heated (500-1000oc) to cause chemical changes in the absence of air.

6. Incineration:-

The incineration involves the burning of solid waste at high temperature (850oc). The unburnt combustibles must be disposed of into the other dumps. The disadvantage of this process is air pollution.

7. Biogas / fertilizer from solid waste:-

In a closed reactor the solid waste should be subjected to anaerobic decomposition to produce the biogas which is used as fuel. The sludge of this process is dried and used as fertilizer/ Management of Solid wastes:-

i) Reduction in use of raw materials: Reduction in the use of raw materials will

correspondingly decrease the production of waste.

ii) Reuse: The refillable containers which are discarded after use can be reused. From

waste paper, silos and casseroles can be made.

iii) Recycle: It is the reprocessing of discarded materials into new useful products.

Formation of some old type products – old Al can melt & recast into new cans. Formation of new products, preparation of fuel pellets form kitchen waste

The process of reducing reusing and recycling saves money, energy raw materials, land space and also reduces pollution.

Role of an individual in prevention of pollution

The role of every individual in preventing pollution is of paramount importance because if every individual contributes substantially the effect will be visible not only at the community, city, state or national level but also at the global level as environment has no boundaries. A small effort made by each individual at his own place will have pronounced effect at the global level. It is aptly said “Think globally act locally.




49

Each individual should change his/her life style in such a way as to reduce environmental pollution. Help more in pollution prevention than pollution control.

Use ecofriendly products

Cut down the use of CFC’s

Use CFC free refrigerators.

Reduce your dependency on fossil fuels

Save electricity by not wasting it when not required

Adopt and popularize renewable energy sources.

Improve energy efficiency

Promote reuse and recycling wherever possible & reduce the production of wastes

Use mass transport system.

Decrease the use of automobiles.

For short distance use bicycle or go on foot.

Use integrated pest management.

Use rechargeable batteries. It will reduce metal pollution

Use less hazardous chemicals

E.g. Baking soda can replace modern deodorants The solid waste generated during one manufacturing process can be used as a raw material

for some other processes.

Use organic manure.

Do not put pesticides, paints, solvents, oils or other harmful chemicals into the drain or

groundwater

Use low PO4, PO4 free or biodegradable dish washing liquid, laundry, detergent &

shampoo.

Use only the minimum required amount of water for various activities. This will prevent

fresh water from pollution.

When building home save as many tree as possible in the area.

Plant more trees.

Check population growth, so that demand of materials is under control.

It is the duty of individual to educate producers and consumers about environmental

degradation and control.

Individuals can help in cleaning beaches, rivers, lakes etc.

The can also help in creating litter free zone, environmental forestry zone, smokeless zone,

noise free zone in the city area.

DISASTER MANAGEMENT

Geological processes like earth quakes, volcanoes, flood and landslides are normal natural events which have resulted in the formation of the earth that we have today. They are, however, disastrous in their impacts, when they affect human settlements.




50

Human societies have witnessed a large number of such natural hazards in different parts of the world and have tried to learn to control these processes, to some extent.

Floods:-

Whenever the quantity of flow of water exceeds the carrying capacity of the channel within its banks, the excess water overflows on to the plains and causes floods. According to the National Commission on floods, the area affected by annual floods now stands at around 40 million hectares. Factors responsible for the occurrence of floods are:- - The flow of excess H2O resulting from increased run off in the catchment area.

- Reduction in carrying capacity of the channel as a consequence of accumulation of

sediments or the obstructions built on flood ways.

- Heavy rainfall and cloud burst

- Sudden and excess release of impounded water behind dams.

- Bursting of man made dams by land slide/earth quakes.

Mitigation Measures:- The flood management plan involves. - Reduction of runoff by increasing infiltration through appropriate afforestation in the

catchment area.

- Limiting discharges by developing detention basins and reservoirs by constructing a series

of check dams in the sub basins.

- Spreading and distributing excess water thinly over such areas as paddy fields, depression,

etc.

- Interlinking of rivers and streams. That is diverting excess water through channels / canals

to the areas and rivers of deficient in water.

- Building impounding reservoirs to store water

- It is imperative to have flood hazard zoning maps & plans of preparedness.

- Encroachment of flood ways should be banned.

- An effective system of flood forecasting and flood warning through networks of station is

an essential part of flood management programme.

Earth quakes:-

An earth quake is a sudden vibration caused on the earth’s surface due to the sudden release of energy stored in the rocks beneath the earth surface. High frequency waves travel in all directions from the focus point and create seismic shocks. The point immediately above the focus is called epicenter. The slight disturbances are known as earth tremors. The instrument used for recording the vibration of earth crust is known as seismograph. The vibrations are recorded on a strip of paper is called seismogram. The severity of an earthquake depends on the amount of energy released. It can be expressed in terms of Richter scale having range up to 10. Effects of the earthquakes:-

- The primary effects of earthquake waves are rupturing the ground and displacing of rock

masses. The ground vibrations cause land slides on hillsides, avalanche on snow covered

mountains and changes in the ground water circulation.




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- Giant sea waves or tsunami are generated in the oceanic realm due to earth quake.

- Damage to valuable human life, destruction of buildings, utility structures, communication

lines, water supply, gas and electricity lines etc are some of the secondary effects of the

earthquakes.

- The earth quake hazards are very severe and wide spread, the annual toll the world over is

of the order 15,000 people.

Mitigation measures:-

Preparation of hazard zoning map: - The pre requisite to cope with seismic hazard is to prepare seismic hazard zone map. Seismic hazard map should give the information of the magnitude and intensity of anticipated earthquakes and likely places of risk. Earthquake Prediction:- The seismologists should be in a position to indicate the possibility of recurrence of earth quakes in a potential area. The most dependable method of forecasting is the analysis of the patterns of micro seismicity that precedes major events. Earthquake resistant houses:-

- The mortality is largely due to house collapse.

- Great attention is to be paid to design and construct earthquake resistant buildings.

- Suggested that the lighter structure buildings are more suitable in seismicity prone area.

- Strange and erratic behaviour of birds & animals become extremely nervous and agitated

are reliable indicators of impending earthquakes.

Cyclone:-

Spirally moving storm developing in the Bay of Bengal and Arabian sea in the tropical belt is called cyclone. The wide spread damage from fierce wind (exceeding 100-120km/hr) is quite common in coastal regions. 1. A cyclone is a circular area of low atmospheric pressure in which the wind blows counter

clockwise direction in the Northern hemisphere.

2. Anticyclone: - It is an area of relatively high pressure in which wind blow spirally outward

in a clock wise direction in the northern hemisphere.

3. Tsunami:- Sometimes, earthquakes occur deep under the sea in oceanic trenches. The

stronger of them generate powerful seismic sea waves called tsunami.

4. Hurricanes and Typhoons: - Spirally moving tropical storms are known as hurricanes in

western countries and typhoons in Asia.

5. Tornadoes: - It usually strikes the central plain of U.S. that are much smaller in

dimensions but rotate violently with speed as high as 800km/hr.

Mitigation measures:-

1. The first step in coastal hazard mitigation programme is the identification and demarcation

on maps of the areas and belts prone to cyclone.

2. Developing Warning system: - Developing an efficient system of monitoring the

movements of cyclone through satellite, radar and air craft. So that advance warning can

be given to the people for reaching safer places.




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3. Reduction of risks in Vulnerable areas:-

i) Settlements must be quite far away from the coast and located behind natural

wind breakers such as sand dune or thick vegetation to reduce the impact of

winds.

ii) Afforestation along coastline prevents wind speed.

Land slides:-

The movement of earthy materials from higher region to lower region in the hilly and sloppy areas due to gravity is called mass movements. If the rock movement, happens through the certain definite plane then it is said to be land slide. Reasons for land slides:- 1. Movement of heavy vehicles on the unstable sloppy regions creates land slides.

2. The tectonic stresses and earthquake shocks create land slides.

3. Internal drainage after rainfall also creates landslides.

4. Erosion in the hilly tract due to run off water also leads to land slides.

5. Excavation in the sloppy region creates condition to failure of slope.

6. In karst topography (limestone region) underground caves may collapse due to subsidence,

underground mining also leads to subsidence.

Mitigation Measures:-

1. Unloading the upper parts of the slope is one of the methods to avoid slope failure.

2. Diverting surface water away from the weak sloppy regions is another method to control land

slides.

3. Improving the vegetation in the sloppy region, reduces erosion & gives strength to soil

4. Slope treatment or slope modification should be made in the steep hilly regions, like

developing benches and reducing the steepness of the slope.

5. Soil stabilization by chemical is also effective in weak area.

6. The weak joints, faulted regions in the sloppy area can be strengthened by means of grouting

(filling of cement slurry in weak zone)

7. Use of retaining wall, buttresses, and pre stressed anchor pads are effective measures.

8. Construction of Cribb walls, Gabions and retaining walls are some other controlling methods.

9. In mines and tunnels, arranging steel bolts and wire mesh/wire net are also useful.

10. Subsidence can be prevented by sand stowing (sand filling)




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UNIT-III

NATURAL RESOURCES

Earth depends on a large number of things and services provided by the nature. A resource is

anything obtained from the environment to meet our needs and wants. Material resources obtained

from the environment are classified as perpetual (such as sunlight, winds and flowing water),

renewable (such as fresh air and water, soils, forest products and food crops), or nonrenewable (such

as fossil fuels, metals and sand)

PERPETUAL RESOURCES:

On a human time scale it is renewed continuously e.g. solar energy. It also includes indirect forms

of solar energy such as winds and flowing water.

RENEWABLE RESOURCES:

Renewable resources can be replenished fairly rapidly through natural processes as long as it is not

used up faster than it is replaced. Renewable resources are inexhaustible and can be regenerated

within a given span of time e.g. forest, wild life, wind energy biomass energy, tidal energy hydro

power etc.

NONRENEWABLE RESOURCES:

Nonrenewable resources exist in a fixed quantity or stock in the earth’s crust. Nonrenewable resources which cannot be regenerated within a short span of time e.g. fossil fuel like coal, petroleum

minerals etc. Once we exhaust these reserves the same cannot be replenished.

Even renewable resources can become non renewable if we exploit them to such extent that

their rate of consumption exceeds their rate of regeneration.

It is very important to protect and conserve our natural resources and use them in a judicious

manner so that we don’t exhaust them.

It doesn’t mean that we should stop using most of natural resources We should use the resources in such a way that we always save enough of them for our future

generations.

FOREST RESOURCES

Forest is one of the land area inhabited by dense growth of trees herbs & shrubs. Maximum

biodiversity has been noticed in the forest area.

Produce innumerable material good.

Provide environmental services essential for life.

About 1/3 of the worlds land area is forested which includes closed as well as open forests.

The cover of natural forest has declined over the years.

The greatest loss occurred in tropical Asia where 1/3rd of the forest resources have been destroyed.

USES OF FOREST:

Commercial uses:

Forest provide us a large number of commercial goods which include timber, firewood, pulpwood,




54

food items, gum, resins, non – edible oils, rubber, fibers, lac, bamboo canes, fodder, medicine, drugs and

many more items, the total worth of which is estimated to be more than $ 300 billion per year.

Half of the timber cut each year is used as fuel for heating and cooking.

1/3rd of the harvest is used for building materials

1/6th of harvest is converted into pulp and used for paper.

Many Forest lands are used for mining, agriculture grazing and recreation and for development of dams. It

also serves as tourist spots by which government gets revenue annually.

Ecological uses:

A typical tree produces commercial goods work about $590 whereas it provides environmental

services worth nearly $ 196250.

Ecological services provided by our forests are as follows.

Production of oxygen:

The trees produce O2 by photosynthesis which is so vital for life on this earth. They are

rightly called as earth’s lungs. Reducing global warming:

The forest canopy act as a sink for CO2 thereby reducing the problem of global warming

caused by green house gas CO2.

Wild life habitat:

Forests are the homes of millions of wild animals and plants. About 7 Million species are

found in the tropical forests alone.

Regulation of hydrological cycle:

Forests water sheds act, like giant sponges absorbing rainfall, slowing down the run off

and slowly releasing the water for recharge of springs.

Soil conservation:

Forests bind the soil particles tightly in their roots and prevent soil erosion. They also act

as wind breaks.

Pollution moderators:

Forests can absorb many toxic gases and can help in keeping the air pure. They have also

been reported to absorb noise and thus help in preventing air and noise pollution.

EXPLOITATION OF FOREST RESOURCES:

With growing civilization the demands for raw material like timber, pulp, minerals, fuel wood etc.,

shoot up resulting in large scale logging, mining and road building and clearing of forest.

Our forests contribute substantially to the natural economy. Excessive use of fuel wood and

charcoal, expansion of urban, agricultural and industrial areas and over grazing have together led to over

exploitation of our forest leading to their rapid degradation.

In the world nearly about 30% of the area is covered by the forest. Developing countries are

rapidly over exploiting their forest wealth by the following two ways.

(i) Increasing agricultural production by destroying forests

(ii) Wood used as fuel.

It has been estimated that minimum area of forests required maintaining ecological balance is about




55

33% of total geographical area unfortunately at present it is only 22.19% in India which is considered to

be very low. The per capital forest land in India is 0.11 hectares as against the world average of 1.08

hectares.

It is reported that Central American countries may lose forests within next 50 years. Ethiopia has last

all but the remaining 3.5% of its forests. Srilanka may lose valuable tropical forest within a period of 20

years. Thailand lost 45% of it forest up to 1985. Indonesia is chopping rain forest at the rate of one

million hectares a year. In Philliphines, 60% of the forests have been cut during the last 30 years.

It is important to reduce the gap between demand and supply of forest material through regeneration

of forests.

DEFORESTATION:

The destruction of forests cover by the activities of man and domestic animals is called deforestation.

The total forest area of the world in 1900 was estimated to be 7000 million ha which was reduced to

2890 million ha in 1975 and fell down to just 2300 million ha by 2000.

Deforestation rate is relatively less in temperate countries but it is very alarming in tropical countries,

where it is as high as 40-50% and at the present rate it is estimated that in the next 60 years, we would

lose more than 90% of our tropical forests.

Now the rate of deforestation has been estimated to be between 25.55 ha / min. The deforestation in

India is about 3.5 million ha /year. Asia has lost almost 95% of its frontier forest.

MAJOR CAUSES OF DEFORESTATION:

1. Growth of human population:

Due to over population requirements of paper shelter, wood, timber, has been increased. Man

has utilized larger area of forests for housing agriculture, factories & railway tracts.

2. Shifting cultivation:

The replacement of natural forest for monoculture can lead disappearance of number of

plant and animal species. 300 million people lived by shifting cultivation. They are supposed

to clear 5 lakhs ha / annum.

3. Industries & Road, Dam construction:

It causes destruction of forest or submergence of forest under water. Hence developmental

activities in the forest area should be discouraged

4. Mining:

Mining activities destroys forest areas

5. Timber extraction:

Due to the increase in the population, the demand for wood also increases which led to

deforestation.

6. Over grazing:

It exposes the soil to erosion by water and wind, compact the soil (which diminishes its

capacity to hold water) and is a major cause of desertification.

7. Forest fire:




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Due to climatic change, human intervention and rise in temperature cause frequent forest

fires which lead deforestation.

8. Fuel requirement:

Increase in demand for fuel wood has shoot up to 300 – 500 Million tons in 2001,

compared to 65 Million ton during independence.

EFFECTS OF DEFORESTATION:

1. Soil erosion:

The fertile topsoil is eroded due to deforestation, which eventually leads to desertification.

6000 million tons of soil gets eroded every year in India.

2. Loss of biodiversity:

Destruction of habitat causes extinction of wild life, which in turn affects ecosystem.

3. Climate change:

Deforestation disrupts the climate pattern which cause drought in one area and heavy rain

in another area.

4. Global warming:

The cutting & burning of forest trees increase the CO2 content in the atmosphere, which in

turn changes the global climate pattern, rising sea levels and depletion of protective ozone layer.

5. Loss of genetic diversity:

The destruction of our forest destroys the greatest store house of genetic diversity on earth,

which provides new food and medicine for the entire world.

6. Hydrological cycle disruption:

Deforestation shifts the hydrologic cycle which cause change in the rainfall pattern in turn

affects the food production.

7. Land slide and floods:

Due to the absence of the trees as barrier, the hilly regions suffer heavy floods and land slides

CASE STUDIES:

Deforestation in hilly regions:

Deforestation in Himalayas involves clearance of natural forest & Plantation of Monocultures like

Pinus, Roxburg, Eucalyptus, Camadulensis etc., have upset the ecosystem, by changing various soil and

biological properties.

The original rich germplasm is lost due to this activity. Areas are invaded by exotic weeds. Areas are not

able to recover & losing the fertility.

The entire west Khosi hill district of Megahalaya in NorthEastern Himalayas, Ladakh, parts of

Kumaon are now facing serious problems of deforestation.

Disappearing Tea gardens in Chhota Nagpur:

This hilly region used to be a good forested area, and used to receive fairly frequent afternoon

showers favouring tea plantation. Towards the turn of the century, following the destruction of forest,

rainfall decline in Chhota Nagpur to such an extent that tea garden also disappeared.




57

PREVENTIVE MEASURES:

1. Creating Awareness

2. Strict implementation of law of forest conservation Act.

3. To counter deforestation, afforestation and social forestry should be adopted.

4. To discourage the Migration of people into the islands from Mainland.

TIMBER EXTRACTION:

Uses of timber: Pulp and paper, composite wood furniture, railways, boats and road construction.

CONSEQUENCES OF TIMBER EXTRACTION:

1. Deforestation

2. Soil erosion, loss of fertility, land slides and loss of biodiversity.

3. Loss of tribal culture & extinction of tribal people.

4. Reduce the thickness of the forest.

Indian Scenario:

Industries consume 28 Million cu.mts / year of wood, but annual forest growth is only about 12

Million cu.mts / year

MINING:

Mining is the process of extracting mineral resources and fossil fuels from the earth.

Surface Mining – shallow deposits

Subsurface mining – deep deposits

80,000ha land of the country is under the stress of mining activities.

Mining and its associated activities required removal of vegetation along with underlying soil

Mantle and overlying rock Masses, this result in defacing the topography and destruction of the landscape

in the area. Large scale deforestation has been repeated in Missouri and Dehradun valley due to

indiscriminate Mining of various minerals over a length of about 40 km. The forest area has declined at an

average rate of 33% and the increase in non – forest area due to Mining activities resulted in unstable

zone leading to landslides.

Indiscriminate Mining in forest in Goa, 1961 destroyed more than 50,000 ha of forest land. Coal

mining in Raniganj cause deforestation. Mining of Magnesite and soap stones have destroyed 14 ha in

Khirakut, Kosi, Almora.

Mining of radioactive Mineral in Kerala, TamilNadu and Karnataka rose similar threats of

deforestation. Rich forest of Western Ghats is also facing the same threat due to Mining projects for

excavation of copper, chromite, bauxite, Magnesite

EFFECTS OF MINING:

1. Mining activity not only destroy trees. It also pollutes soil, water, with heavy Metal toxins that are

almost impossible to remove.

2. Destruction of natural habitat

3. Due to continuous removal of Minerals & forest covers, trenches are formed on ground leading to

water logged area which in turn contaminate ground water

4. Noise pollution due to Mining operations

5. Lands slides may also occur as a result of continuous Mining in forest area.




58

6. During Mining, vibrations are developed which leads to earthquake

7. When materials are distributed in significant quantities, during mining process large quantities of

sediments are transported by water erosion.

TIMBER EXTRACTION AND MINING: The major activities in forest area are 1. timber extraction 2. mining The important effects of timber extraction are

i) thinning of forests ii) loss of biodiversity, particularly tree breading species iii) soil erosion and loss of soil fertility iv) migration of tribal people from one place to another in search of new forest v) extinction of tribal people and their culture

MINING: Mining is a process of removing ores from area which is very much below the ground level. Mining is done for the extraction of several minerals of metals like Fe, Mn, Au, Ag,etc. The minerals are especially found in thick forests.

Mining can be carried out in two ways

1. Surface mining 2. underground mining or sub-surface mining

The effects of under ground mining on forest reserves is comparatively less than that of surface mining Relation between forest and climate change: Forests both influence and influenced by climate change. They play an important role in the carbon cycle and the way we manage forests could significantly affect global warming. Forests hold more than 50 per cent of the carbon that is stored in terrestrial vegetation and soil organic matter. Hence, deforestation contributes significantly to net emissions of carbon dioxide into the atm. If the predicted global warming occurs, the impact on forests is likely to be regionally varied, dramatic, and long-lasting. Even now, we can see how any extreme weather has great impact on forests. For example, the 1999 storms in Europe caused heavy damage to forests and also to trees outside forest areas. The Kyoto Protocol on climate change may have a great impact on forest management. Under the Protocol, a country with forests earns emission credits, since its forests absorb carbon dioxide. These credits are tradable, that is, a developing country can sell its credits to an industrialized country that has exceeded its quota of emissions. The latter would invest in afforestation and reforestation projects in the developing country. DAMS – BENEFITS AND PROBLEMS River valley projects with big dams are considered to play a key role in the development of a country. India has large number of river valley projects

1. These dams are regarded as symbol of national development.




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2. provides large scale employment of tribal people and increase the std. of living of them 3. contribute for economic uplift and growth 4. help in checking flood 5. generate electricity 6. reduce power and water shortage 7. provide irrigation water 8. provide drinking water to remote areas 9. promote navigation and fishery.

Environmental problems:

The environmental problems can be at upstream as well as downstream

Level

Upstream problems

1. Displacement of tribal people 2. Loss of flora and fauna 3. siltation and sedimentation near reservoir 4. stagnation and water logging near reservoir 5. growth of aquatic weeds 6. micro climatic changes 7. RIS causes earthquakes 8. breeding of disease vectors

Downstream problems

1. Water logging and salinity due to over irrigation 2. micro climatic changes 3. salt water intrusion at river mouth 4. loss of fertility due to sediment deposits 5. out break of vector born diseases.

DAMS AND THEIR EFFECTS ON FOREST AND PEOPLE:

India has more number of river valley projects (RVP) referred to as “Temples of Modern India”. Dams are responsible for the destruction of vast areas of forest.

India has more than 1550 large dams. Maximum number of dams in the state of Maharastra (600)

followed by Gujarat (more than 250) and Madhya Pradesh (130). The highest one is Tehri dam on river

Bhagirathi in Uttranchal & the largest in terms of capacity in Bhakra dam on river Sutlej in Himachal

Pradesh.

Big dams have been in sharp focus of various Environmental groups all over the world which is

mainly because of several ecological problems related to tribal or native people associated with them.

EFFECTS OF DAM ON FOREST:




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Large scale devastation of forests takes place which breaks the natural and ecological balance of

the region.

Big RVP also caused water logging which leads to reduce fertility of land.

Floods, drought & land slides become more prevalent in mining area

The impounding of water in the dam may create Major / Minor earthquakes and leads to flood in

the down stream side of a dam.

Forests are the repositories of invaluable gifts of nature in the form of biodiversity. By destroying

them, we are going to lose these species even before knowing them.

These species could be having marvelous economic or medicinal value and deforestation results in

loss of their store house of species, which have evolved over millions of years in single stroke.

EFFECTS OF DAM ON TRIBAL PEOPLE

1. The greatest social cost of big dam is wide spread displacement of tribal people.

2. The displacement & cultural change affects the tribal people mentally (or) physically. They do not

accommodate the modern food habits and life styles.

3. Tribal people may be ill treated by modern society

4. Tribal people & their culture cannot be questioned and destroyed.

5. Many of the displaced people were not recognized and resettled (or) compensated (Environmental

refugees)

world forest day – march 21st

Sardar Sarovar Dam (uprooted forests and Tribes):

A case study:

The dam is situated on river Narmada and is spread over three states of Gujarat,

Maharashtra and Madhya Pradesh. Although the project is aimed at providing irrigation water,

drinking water and electricity to three states, the environmental impacts of the project have raised

challenging questions.

A total of 1, 44,731 ha of land will be submerged by the dam, out of which 56,547 ha is

forest land. A total of 573 villages are to be submerged by the Narmadha Dam.

Submergence of about 40,000 ha of forest under Narmada sagar, 13,800 ha under Sardar

Sarovar and 2,500 ha under Omkareshwar would further create pressure on remaining forest areas

in adjoining areas submergence area is very rich in wild life e.g. tigers, panthers, bears, wolves,

pangolins, hyenas, jackals, flying squirrels, antelopes, black bucks, chinkara, marsh crocodiles,

turtles etc. Many of these species are listed in schedule 1 & 11 of wild life protection Act, 1972.

Thus massive loss of these wild life species is apprehended due to the devastation of the forest

under the project.

As per the estimates of the Institute of urban Affairs, New Delhi, the Narmadha Valley

project will lead to eventual displacement of more than one million people, which is probably the

largest rehabilitation issue ever encountered as per the world Bank. Uprooting of the tribes and

their forced shifting in far – flung areas may not be easily adjusted to. Besides serious economic

deprivation, the displacement will affect the tribal people’s culture, their beliefs, myths and rituals, festivals, songs and dances, all closely associated with the hills, forests and streams. Most of these




61

tribes are being uprooted from a place where they have lived for generation. The displaced

persons have to undergo hardship and distress for the sake of development and prosperity of a

larger section of the society. It is therefore the duty of the project proponents and government to

pay maximum attention for proper rehabilitation of the displaced tribes.

WATER RESOURCES World Water Day – March 22

About 71% of the earth surface is salt water. All the organisms are made up mostly of

water.

A tree is about 60% water by weight

Animals having 50 – 65 % water.

It plays a major role in sculpting earth’s surface, Moderating climate, diluting pollutants. IMPORTANT PROPERTIES OF WATER:

There are strong forces of attraction between molecules of water (Hydrogen bond)

Water exists as a liquid over a wide temperature range because of the strong forces of attraction

between water Molecules.

Its high boiling point 100C and low freezing point 0oC means that H2O remains a liquid in most

climates on the earth.

Water changes temperature slowly because it can store a large amount of heat without a large

change in temperature. High heat capacity helps (1 cal / 1C/ 1 gm)

(i) Protect living organism from temperature fluctuation.

(ii) Moderates climates

(iii) Excellent coolant.

Evaporating liquid water takes large amounts of heat because of strong force of attraction between

its molecules.

1. H2O absorbs large amount of heat as it changes into H2O vapor and releases this

heat as the vapour condenses back to liquid

2. This helps distribute heat throughout the world

It can dissolve a variety of compounds

- It enables it to carry dissolved nutrients to tissues.

- It flushes the waste products out of those tissues.

- It serves as an all – purpose cleaner

- It helps to remove and dilute the water soluble wastes of civilization.

- It can ionize water Molecules into H+ & OH-

- To maintain a balance between acids & bases in cell organism

- Water filters out the wavelengths of UV radiation that would harm some aquatic organism.

Strong attractive forces between the molecules of water causes it surface to contract (high surface




62

Tension) and to adhere to and coat a solid (capillary action) (73 dynes /cm at 18C – surface

tension of water)

Water expands when it freezes and become less dense than water. Otherwise lakes and streams in

cold climate would freeze solid and lose most of their current forms of aquatic life.

- H2O expands on freezing can break pipes (soil formation).

- Water is the life blood of biosphere

- Water is one of our poorly Managed resources.

- We waste it and pollute it we charged too little for making it available. This encourages

still greater waste and pollution of this resource, for which we have no substitute.

- Benjamnin Franklin statement “It is not until the well runs dry that we know the worth of H2O”.

AVAILABILITY OF FRESH WATER:

Only a tiny fraction of the planet’s abundant H2O is available to us as fresh water.

About 97.4% by volume is found in the oceans and is too salty for drinking irrigation or industries.

Most of remaining 2.6% that is fresh water is locked up in ice caps or glacier or in ground water

too deep or salty to be used.

All water Fresh water Readily accessible water

Thus the only about 0.014% of earth’s total volume of water is easily available to us as soil Moisture, usable Ground water, water vapour, lakes and streams. If world’s H2O supply were only 100L,

our usable supply of fresh water would be only 0.014 litres (2.5 tea spoons)

This water is continuously collected, purified & recycled & distributed in the solar powered

hydrologic cycle.

This works only as long as we do not overload water system with slowly degradable & non

degradable wastes or with draw water from underground supplies faster than it is replenished.

Differences in average annual precipitation divide the world country and people into water haves and

have nots.

For e.g. Canada with only 0.5% world’s population has 20% of world’s usable water, whereas China with 21% of world’s population has only 7% of supply. Global warming can increase global rates of evaporation, shift precipitation pattern and disrupt

H2O supplies and thus food supplies.

Oce

an9

7.4

%

Fresh water2.6%

Ice caps & glaciers1.98%

Ground water 0.592%

0.014%

Soil moisture 0.005%

Lakes 0.007%

Water vapour

0.001%

Rivers 0.0001%

Biota 0.0001%




63

Some areas will get more precipitation and some less, some rivers flow will change.

THE HYDROLOGIC CYCLE:

In hydrologic cycle, H2O continuously moves from the atmosphere to the land, plants, oceans and

fresh water bodies and then back into the atmosphere. It consists of number of stages.

1. The largest amount of water transferred in any segment of the total cycle is those involved in the

direct evaporation from the sea to the atmosphere and in precipitation back to the sea.

Evaporation:

By which H2O changes from liquid to the gaseous form.

Precipitation:

It includes any liquid H2O or ice that falls to the surface through atmosphere.

2. The passage of H2O to the atmosphere through leaf pores is called transpiration and term

evapotranspiration encompasses the process by which water evaporates from the land surface and

plants. Evapotranspiration combines with the precipitation of water onto the land surface to play a

quantitatively smaller, but possibly more important.

3. If surplus precipitation at the land surface does not evaporate. It is removed via the surface

network of streams & rivers, a phenomenon called runoff. The runoff includes some H2O that

flows beneath the surface & eventually find its way to rivers & Oceans

It can be viewed as closed system, in which water is continuously moved among the component

spheres of earth system.

Water circulates between the lower atmosphere, upper Lithosphere, the plants of the

biosphere and the oceans of hydrosphere. The system can also be split into two subsystems. One

consisting of the precipitation and evaporation over the oceans and the other involving

evapotranspiration and precipitation over land areas. The two subsystems are linked by horizontal

movement in atmosphere and by surface runoff flows.

The time required for H2O to traverse the full cycle can be quite brief. A molecule of

water can pass from ocean to the atmosphere and back again within a matter of days. Over land,

cycle is less rapid. Ground water goes into soil or subsurface and can remain there for weeks (or)

months.

The circulation is even slower where H2O in the solid form of ice is concerned. Some H2O

has been locked up in Major ice sheets and glaciers for many thousand years.

Surface Water:

Surface run off precipitation that does not infiltrate the ground or return to the atmosphere or

return to the atmosphere by evaporation (including transpiration). This runoff flows into streams, lakes,

wetlands, estuaries and reservoirs.

Watershed:

A water shed, also called a drainage basin is a region from which water drains into a stream, Lake,

reservoir, wetland, estuary, or other body of surface water.

Ground Water:

Some precipitation infiltrates the ground and percolates downward through voids (pores, fractures,




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crevices, and other spaces) in soil and rock. The water in these voids is called groundwater.

Aquifers:

Porous, water – Saturated layers of sand, gravel, or bedrock through which groundwater flows are

called Aquifers.

Use and over Utilization of fresh water:

Use of fresh water supply:

During the last century the human population tripled. According to a 2002 report by the United

Nations, during this period our global water withdrawing (use) increased sevenfold and per capita

withdrawal quadrupled. As a result, we now with draw about 35% of the world’s reliable runoff. We lease another 20% of this runoff in streams to transport goods by boats, dilute pollution, and sustain

fisheries and wildlife. Thus we directly or indirectly are already using about 55% of the worlds reliable

run off of surface water. Because of increased population growth and economic development, global

withdrawal rates of surface water could reach more than 70% of the reliable surface runoff by 2025 and

exceed such runoff in growing number areas. Uses of withdrawn water vary from one region to another

and from one country to another. Worldwide, about 69% of water withdrawn each year from rivers, lakes

and aquifers is used to irrigate 17% of the world’s cropland and produce about 40% of the world’s food. Industry uses about 23% of the water withdrawn each year, and cities and residences use the

remaining 8% Agriculture and manufacturing use large amounts of water.

Some of the water withdrawn from a source may be returned to that source of or reuse.

Consumptive water use occurs when water withdrawn becomes unavailable for reuse in the basin from

which it was removed – mostly because of losses such as evaporation or contamination.

FRESHWATER SHORTAGES:

According to Swedish hydrologist Malin Falkenmark, there are four causes of water scarcity i) a

dry climate, ii) drought (a period of 21 days or longer in which precipitation is at least 70% lower and

evaporation is higher than normal), iii) desiccation (drying of exposed soil because of such activities as

deforestation and overgrazing by livestock), and iv) water stress (low per capitation availability of water

caused by increasing number of people relying on limited runoff levels.

Increase Freshwater Supplies

There are several ways to increase the supply of freshwater in a particular area.

Build dams and store reservoirs to run off for release as needed.

To bring in surface water from another area.

Withdraw groundwater and

Convert salt water to fresh water (desalination).

Other strategies are to reduce water waste and import food to reduce water use in growing food. Each

imported metric ton of grain saves roughly, 1,000 metric tons of water needed to produce the grains.

Advantages and Disadvantages of Large Dams and Reservoirs:

Large dams and reservoirs have benefits and drawbacks. Their main purpose is to capture and

store run off and releases it as needed for controlling floods, producing hydroelectric power




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and supplying H2O for irrigation and for towns and cities.

Reservoirs also provide recreational activities such as swimming, fishing and boating.

Advantages:

1. Generates electricity at cheaper rates.

2. Reduces dependence on coal.

3. Reduces air pollution.

4. Reduces CO2 emission

5. Reduces chances of downstream flooding

6. Reduces river sitting below dam by eroded soil.

7. Increases irrigation water for cropland below dam

8. Useful for recreation and fishing.

Disadvantages:

1. Floods large areas of cropland and forests

2. Displaces people

3. Increase water pollution because of reduced water flow

4. Reduce deposits of nutrient rich sediments below dam

5. Increases salt water introduced into drinking water near mouth of river because of decreased water

flow.

6. Disrupts spawning and migration of some fish below dam.

7. Modifies ecosystem and hydrologic regimes in areas both upstream and down stream.

8. Storing water create hydraulic pressure and leads to seismic tremors.

9. Structural defects in the dam, cause it to collapse suddenly and destroy many living organisms

10. High Cost.

Withdrawing Ground water

Aquifer provides drinking water for about 1/4 th of the world’s people. Advantages:

1. Good source of water for drinking and irrigation

2. Available year around

3. Exist almost everywhere

4. Renewable if not over pumped or contaminated

5. No evaporation losses.

6. Cheaper to extract than most surface water.

Disadvantages:

1. Aquifer depletion from over pumping

2. Sinking of tend when water removed

3. Polluted aquifers instable for decades or centuries

4. Salt water intrusion into drinking water supplies near coastal areas.

5. Reduced water flows into streams, lakes, estuaries and wet lands.

6. Increased cost, energy use, and contamination from deeper wells.




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Ground Water Depletion:

Prevention:

1. Waste Less Water

2. Subsidize water conservation

3. Ban new wells in aquifers near surface water.

4. Buy and retire ground water withdrawal rights in critical areas.

5. Do not grow water intensive crops in dry areas

6. Reduce birth rates.

Control:

1. Raise price of water to discourage waste

2. Tax water pumped from wells near surface waters.

3. Set and enforce minimum stream flow levels.

Reducing water Waste:

World Resource Institute estimates that 65- 70% of the water people use throughout the world is

lost through evaporation, leaks and other losses.

It is economically and technically feasible to reduce such water losses to 15% thereby meeting

most of the worlds water needs for the foreseeable future.

Prevention method for reducing water in Irrigation:

1. Lining Canals bringing water to irrigation ditches

2. Irrigation at night to reduce evaporation.

3. Using soil and satellite sensors and computer systems to monitor soil moisture and add water only

when necessary.

4. Poly culture

5. Organic farming

6. Growing water efficient crops using drought resistant and salt tolerant crop varieties

7. Irrigation with treated urban waste water

8. Importing water intensive crops.

Reducing Water waste in Industries, homes and businesses:

1. Redesign manufacturing process

2. Landscape yards with plants that required little water

3. Use drip irrigation

4. Fix water Leaks

5. Use water meter and charge for all municipal water use.

6. Raise water Prices.

7. Require water conservation in water short cities.

8. Using water – saving toilets, shower heads and front loading clothes washers.

9. Collect and reuse house hold water to irrigate lawns and non edible plants.

10. Purify and reuse water for houses, apartments and office buildings.




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Case Study:

The Cauvery water dispute:

Out of India’s18 major rivers 17 are shared between different states. In all these cases, there are intense conflicts over these resources, which hardly seem to resolve. The Cauvery river water is bone

of contention between TamilNadu and Karanataka and the fighting is almost hundred years old.

TamilNadu occupying, the downstream region of the river wants water use regulated in the upstream,

whereas the upstream state Karnataka refuses to do so and claims its primacy over the river as

upstream user. The river water is almost fully utilized and both the states have increasing demands for

agriculture and industry. On June 2, 1990 the Cauvery H2O dispute tribunal was set up which through

an interim award directed Karnataka to ensure that 205 TMCF of water was made available in Mettur

every year till settlement was reached. In 1995, situation turned into crisis due to delayed rain and an

expert committee was set up to look into the matter which found that there was a complex cropping

pattern in Cauvery basin. Proper selection of crop varieties optimum use of H2O better rationing,

rational sharing patterns and pricing of water are suggested as some measures to solve the problems.

FOOD RESOURCES

Human have depend on three systems for their food supply. Croplands mostly produce grains and

provide about 76% of the world’s food. Range lands produce meat mostly from grazing live stock and supply about 17% of the world’s food. Oceanic fisheries supply about 7% of the world’s food. Since 1950 these has been a staggering increase in global food production from all three systems,

because of technological advantages.

To feed the world’s 9.3 million people projected by 2050, we must produce and equitably distribute more food than has been produced since agriculture began about 10000, years ago and do this in

an environmentally sustainable manner.

Other analysts contend that environmental degradation, pollution, lack of water for irrigation,

overgrazing by live stock, overfishing and loss of vital ecological services may limit future food

production.

A key problem is that human activities continue to take over or degrade more of plants net primary

productivity.

The earth has perhaps 30,000 plant species with parts that people can eat. However, only 15 plant

and 8 terrestrial animal species supply an estimated 90% of our global intake of calories.

Just three grain crops – wheat, rice and corn – provide more than half the calories people consume.

These grains are annual. Two – thirds of the world’s population survives primarily on traditional grams mostly because they cannot afford meat. As incomes rise, people consume more grain, but indirectly in

the form of meat, eggs, milk cheese and other products of grain eating domesticated live stock.

Fish and shell fish are an important source of food for about 1 billion people in Asia & in coastal




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areas of developing countries. But on global scale, it supply only 7% of the world’s food. World food problems:

The Food and Agriculture Organization (FAO) of UN estimated that on an average of the

minimum calorie intake on a global scale is 2500 calories/day People receiving less than 90% these

minimum dietary calories are called under nourished and if it is less than 80% they are said to be seriously

undernourished. Besides the minimum calorie intake we also need proteins, minerals etc. Deficiency or

lack of nutrition often leads to malnutrition resulting in severe diseases.

During the lost 50 years world grain production has increased almost three times, thereby

increasing per capita production by about 50%.

But at the same time population growth increased at such a rate in LDC (Less developed

countries) that it outstripped food production.

Every year 40 million people die of undernourishment and malnutrition (fifty percent of which are

young children between 1 to 5 years.

This means that every year our food problem is killing as many people as were killed by the

atomic bomb dropped on Hiroshima during World War II.

These startling statistical figures more than emphasize the need to increase our food production,

equitably distribute it and also to control population growth.

Indian Scenario:

Although India is the third largest producer of staple crops an estimated 300 million Indians are

still under nourished. India has only half as much land as USA but it has nearly three times population to

feed.

The World food summit, 1996 has set the target to reduce the number of under nourished to just

half by 2015, which still means 410 million undernourished people or earth.

Charges caused by Agriculture:

Agriculture has significant harmful effects on air, soil, water & biodiversity.

Some analyst believes these harmful environmental effects can be overcome and will not limit

future food production. Other analysts disagree. The future ability to produce more food will be limited

by a combination of environmental factors. They include soil erosion, desertification, salinization and

water logging of irrigated land, water deficits and droughts loss of wild species that provide the genetic

resources for improved forms of foods and the effects of global warming in some parts of the world.

According to a 2002 study by UN Department, close to 30% of world’s cropland has been degraded by sail erosion, salinity and chemical pollution and 17% has been seriously degraded.

Major Environmental effects of Agriculture:

1. Soil Problems:

a) Soil erosion

b) Loss of fertility

c) Salinization

d) Water logging

e) Desertification

2. Water Problems:




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a) Aquifer depletion

b) Increased runoff and flooding from land cleared to grow crops.

c) Sediment pollution from erosion

d) Fish kills from pesticides

e) Surface & ground water pollution from pesticides and fertilizers.

f) Over fertilization of Lakes and slow moving rivers from run off of nitrates and phosphates from

fertilizer livestock wastes and food processing wastes.

3.Bio diversity loss

a) Loss and degradation of habitat from clearing grasslands and forests and draining wetlands

b) Killing of wild predators to protect stock

c) Loss of genetic diversity from replacing thousands of wild crop strains with a few mono culture

strains.

4. Air pollution:

a) Green house gas emission from fossil fuel use

b) Other air pollutants from fossil fuel use

c) Pollution from pesticide sprays.

5.Human Health :

a) Nitrates in drinking water

b) Pesticide residues in drinking water food and air

c) Contamination of drinking and swimming water with disease organisms from live stock wastes.

d) Bacterial contamination of meat

Effects of over grazing:

Overgrazing can limit livestock production. Overgrazing occurs when too many animals graze for

too long and exceed the carrying capacity of a grassland area. Excessive numbers of domestic livestock

feeding for too long in particular area causes most overgrazing.

Such overgrazing lowers the net primary productivity of grassland vegetation and reduces grass cover. It

also and exposes the soil to erosion by water and wind, compacts the soil (which diminishes its capacity

to hold water) and is a major cause of desertification.

Some grass land can suffer from under grazing where; absence of grazing for long periods (at least

5 years) can reduce the net primary productivity of grassland Vegetation and grass cover. Moderate

growing of such areas removes accumulation of standing dead material and stimulates new biomass

production.

Modern Agriculture and its impacts

It makes use of hybrid seeds of selected and single crop variety, high – tech equipment and lots of

energy subsidies in the form of fertilizers, pesticides and irrigation water.

i) Impact related to high yielding varieties (HYV)

The uses high yielding varieties (HYV) encourage monoculture. Incase of an attack by some

pathogen, there is total devastation of the crop by the disease due to exactly uniform conditions which

help in rapid spread of disease.




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ii) Fertilizer related Problems

a) Micronutrient imbalance:

Excessive use of fertilizers cause micronutrient imbalance. For e.g. excessive fertilizer use in

Punjab and Haryana has caused deficiency of the Micronutrient Zinc in the soils, which is affecting

productivity of the soil.

b) Nitrate Pollution:

Nitrogenous fertilizers applied in the field often reach deep into the soil and ultimately

contaminate the ground water. When their concentration exceeds 25 mg /l, they become the cause of a

serious health hazard called blue baby syndrome or methaemoglobinemia and cause death in infants.

c. Eutrophication:

Excessive use of nitrogen and Phosphate fertilizers in the agricultural fields leads to another

problem (eutrophication). A large proportion of N and P used in crop fields is washed off along with run

off water reach the water bodies causing over nourishment of the lakes a process known as

Eutrophication. Due to eutrophication the lakes get invaded by algal blooms. They are toxic & badly

affect the food chain. The algal species quickly complete there life cycle and die thereby adding a lot of

dead organic matter. The fishes are also killed. Oxygen is consumed in the process of decomposition and

very soon the water gets depleted of dissolved oxygen. This causes an anaerobic condition where,

pathogenic anaerobic bacteria can survive.

iii) Pesticide related problems:

Thousands of types of pesticides are used in agriculture. The first generation pesticides include

chemicals like sulphur, arsenic, lead or mercury to kill the pest. DDT belongs to second generation

pesticide. After 1940, a large number of synthetic pesticides came into use. Although these pesticides

have gone a long way in protecting our crops from huge losses occurring due to pests, yet they have a

number of side effects as discussed below.

a. Creating resistance in Pests and producing new pests:

Some individuals of pest species usually survive even after Pesticides spray. The survivors

give rise to highly resistant generation. Pests which have become immune to all types of Pesticides are

known as super pests.

b. Death of non target organism:

Many insecticides are broad spectrum poisons which not only kill the target species but also

several non target species that are useful to us.

c. Biological Magnification:

Many of Pesticides are non bio degradable and keep on accumulating in the food chain a process

called biological magnification

Salinity:

Approximately 17% of the world’s cropland that is irrigated produces almost 40% of the world’s food. Irrigated land can produce crop yields two or three times greater than those from rain watering.

But irrigation has a downside. Most irrigation water is a dilute solution of various salts, picked up

as the water flows over or through soil and rocks. Small quantities of these salts are essential nutrients for




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plants, but they are toxic in large amounts.

Irrigation water not absorbed into the soil evaporates leaving behind a thin crust of dissolved salts

in the top soil. This accumulation of salts is called salinization, which stunts crop growth, lowers crop

yields and eventually kills plants and ruins the land.

According to a 1995 study, severe salinization has reduced yields on 21% of the world’s irrigated cropland and another 30% has been moderately salinized. The most severe salinization occurs in Asia

especially in china, India, and Pakistan.

Water Logging:

Farmers often apply large amounts of irrigation water to leach salts deeper into the soil. Without

adequate drainage, however water accumulates underground and gradually raises the water table.

Saline water then envelops the deep roots of plants, lowering their productivity and killing them

after prolonged exposure. At least one – tenth of all irrigated land world wide suffers from water logging

and the problems is getting worse. Under water logged conditions pore spaces in the soil get fully

drenched with water and soil air gets depleted. Water table rises while the roots of plants do not get

adequate air for respiration Mechanical strength of the soil declines, crop plants get lodged and crop yield

falls.

Soil Salinization:

Prevention:

1. Reduce irrigation

2. Switch to salt tolerant crops such as (barley, cotton, sugar beet)

Control

1. Flushing soil (expensive and wastes water)

2. Not growing crops for 2- 5 years

3. Installing underground drainage system (expensive)

Sustainable Agriculture

Components of more sustainable, low through put agriculture

More Less

1. High yield poly culture 1. Soil erosion

2. Organic fertilizers 2.Soil Salinization

3. Biological pest Control 3.Aquifier depletion

4. Integrated Pest Management 4.Over grazing

5. Irrigation efficiency 5.Over fishing

6. Perennial crops 6.Loss of biodiversity

7. Crop rotation 7.Loss of Prime cropland

8. Use of more water efficient crops 8.Food waste

9. Soil conservation 9.Subsidies for unsustainable farming and

fishing

10. Subsidies for more sustainable farming

and fishing

10.Population growth




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11.Poverty

Case Study:

Salinity and water logging in Punjab, Haryana and Rajasthan:

The first alarming report of salt – affected wasteland formation in connection with irrigation practices

came from Haryana (then Punjab) in 1858. It was reported that several villages in Panipat, Rohtak and

Delhi lying in command area of western Yamuna Canal were suffering from destructive saline

efflorescence. The “Reh Committee” in 1886 draw the attention of the government on some vital points showing a close relationship between irrigation, drainage and spread of “reh” and “ usar” soils. The foods of 1947, 1950, 1952, 1954 – 56 in Punjab resulted in aggravated water logging with

serious drainage problems introduction of canal irrigation in 1.2 m ha in Haryana resulted in rise in water

– table followed by water – logging and salinity in many irrigated areas causing huge economic losses as

a result of fall in crop productivity. Rajasthan too has suffered badly in this regard following the biggest

irrigation project “ Indira Gandhi Canal Project” and the suffering of a big area in western Rajasthan have changed from a condition of “ water – starved wasteland” to that of a “water – soaked wasteland”.

ENERGY RESOURCES

Energy is capacity to do work. Energy resources are classified into renewable energy resources and non

renewable energy resources.

Non renewable energy resources are finite and cannot be replaced after being used.

E.g. fossil fuel, natural gas etc

Renewable energy resources are indefinitely renewable or naturally replenished after being used

by man and are not likely to be exhausted by man’s use E.g. Sunlight, wind, tide, biomass etc.

Non Renewable energy

Main sources of energy in the industrialized world are fossil fuel and Mineral fuels

Carbon containing natural resources- include solid (coal), liquid (Petrol) and gas (Natural gas) fuel.

Formed from fossilised remains of pre historic plants and animals

Coal

- most common source of energy

- 60% of commercial energy consumption is met by coal

- Indian stands 5th place.

- Different types of coal Anthracite (high quanlity coal, high heat content) Bituminous,

high heat content as well as high sulphur content) lignite ( low heat content ) peat (low heat

content )

- Coal is Pollutant, when burnt it produces CO2 and CO

Petroleum:

- Most important component of commercial energy 40% energy fed by Petroleum

- High heat content

- Burns without ash or smoke.




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- Produce Pollutants such as sulphur oxides CO, Lead etc.

Natural gas:

- an alternative substitute for oil

- It is one of the cleanest fossil fuel

- It burns completely leaving no ash or smoke

- High heat content.

- Transportation of gas cost is high

- Large reserves are estimated to be located in inaccessible areas.

Renewable energy Sources:

(Non – Conventional energy source) Can be renewed again and again either by fostering their growth

with efficient management or they may be available in nature permanently without depletion.

Non – Conventional energy: to conserve conventional energy resource and to meet the energy

crisis, efforts were made for developing new sources of energy. These are called non – conventional

energy sources.

E.g. Solar, wind, tidal, biogas & geothermal

Growing energy needs:

Development in different sectors relies largely upon energy. Agriculture, Industry mining,

transportation, lighting, cooling & heating in buildings all need energy.

With demands of growing population the world is facing further energy deficit.

Fossil fuels at present are supplying 95% of the commercial energy of the world resources.

Developed countries like U.S.A. & Canada constitute about 5% of the world’s population, but consume one fourth of global energy resources.

An average person there Ethiopia, Nepal & Bhutan consumes less than 1 GJ in a year.

Our life style and standards of living are closely related to energy needs.

Alternate energy sources:

Solar energy:

A solar collector is basically a flat box and are composed of three main parts, a transparent cover, tubes

which carry a coolant and an insulated back plate. The solar collector works on the green house effect

principle; solar radiation incident upon the transparent surface of the solar collector is transmitted through

though this surface. The inside of the solar collector is usually evacuated, the energy contained within the

solar collect is basically trapped and thus heats the coolant contained within the tubes. The tubes are

usually made from copper, and the backplate is painted black to help absorb solar radiation. The solar

collector is usually insulated to avoid heat losses.




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Active solar water heating

The main components on an active solar water heating system are

Solar collector to capture the suns energy and to transfer is to the coolant medium

A circulation system that moves the fluid between the solar collector and the storage tank

Storage tank

Back up heating system

Control system to regulate the system operation

The two main types of solar water heating systems are the closed loop system and the open loop system.

The open loop system used water as the coolant, the water circulates between the solar collector and the

storage tank.

There are two main types of open loop system these are the draindown system and the recirculating

system, the main principle behind both systems is the activation of circulation from the collector to the

storage tank when the temperature within the solar collector reaches a certain value.

In the drain down system a valve is used to allow the solar collector to fill with water when the collector

reaches a certain temperature.

In the recirculating system water is pumped through the collector when the temperature in the storage

tank reaches a certain critical value.

In applications where there is likely to be a temperature drop below zero degrees then it is necessary to

use a closed loop system. The main difference between the open loop system is the water is replaced with

a coolant which will not freeze in the temperature range which the solar collector may be subject to. The

coolant will usually be refrigerant, oil or distilled water. Closed loop systems are generally more costly

than their open loop counter parts and great care must be taken to avoid contamination of the water with

refrigerant. The energy captured by the coolant is then transferred to the hot water via a heat




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exchanger. In a drainback system the coolant may be distilled water. The system works on the principle

that there is only water in the collector when the pump is operating. This has the benefit that the coolant

used in the system will not have the chance to cool down during the night when temperature may drop to

a level which may cause the coolant to increase in density and thus perhaps cause is not be as free flowing

as it should. The only necessary feature on the drainback system is that the solar collectors are elevated

from the heat exchanger or drainbak tank in order for the coolant to flow out of the collector. This system

again works on the principle that the water is circulated between the collector and the drainback tank

when the designated temperature is reached between the solar collector and the hot water.

Active solar space heating

The system components in a space heating application are the same for water heating with the addition of

radiators for space heating or under floor heating coils or even forced air systems.

A radiator system will generally work in a very similar manner to the hot water application, the main

difference is the inclusion of a boiler, heated water from the collector is passed through the heat

exchanger or drainback tank and is then passed to a boiler with is used to supplement the water hearing

requirements before passing into the radiators to be used for space heating.

Air distribution systems.




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Again the air distribution system works in a manor very similar to the hot water system, the main

difference is the inclusion of a blower and an air duct. The system uses an additional controlled which

will allow air flow over the coil when the temperature in the storage tank is high enough that passing air

over the coils in the return duct of the apparatus will allow the system to make a positive contribution to

the heating space heating demand.

In large commercial or industrial applications system design is slightly different from residential

applications. It is worth noting that the temperature rise across a collector is fairly constant to use an

example if the temperature of supply to the collector is around 60F and the temperature of return is

around 73oC or the return is 173F and the supply is 160C, this basically means that high and low

temperature applications should not be put in series inside a loop. The low temperature application would

basically drag down the higher temperature application. Vacuum collectors are excellent performers in

high temperature applications the collector loop should be dedicated to the higher temperature application

until the load is satisfied. In applications such as for hospitals, hotels or commercial office blocks are may

be necessary for the installation of two or more tanks connected in series.

1. storage tank 2. preheat tank 3. cold feed 4.mixing valve 5. supply and return to collector 6. hot water

out

system operation: Hot water from the collector passes through the coil in tank one (1), Then, depending

on it's temperature, it is diverted by a three way valve (4) to either: the coil in tank (2) if it is above




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the set temperature, (meaning tank (1) is hot) or the collector, if it is below the set temperature of the

mixing valve.

Commercial and industrial design considerations: The system can be expanded to include more than one

preheat tanks, the heat exchange coils are linked by three way valves and the water which is to be heated

runs in series through the tanks in the opposite direction. The three way valve can either be thermally

controlled or electrically operated. No more than 100 tubes should be plumbed in series. Care must be

taken when designing the pipe work in each section to ensure that each section receives equal flow.

Advantages Disadvantages

Save money Making solar cells produces toxic chemicals

Reduce air pollution 99% less than coal Solar systems last only 30 – 40 years.

Greatly reduce CO2 emissions Solar cells & Solar thermal take large

amounts of land because of diffuse nature of

sunlight.

Last as long as coal and nuclear plants Can damage fragile desert ecosystem used to

collect Solar energy

Back up and storage device available (gas

turbine, batteries, flywheel)

Need back up systems at night and during

cloudy and rainy weather.

Back up need reduced by distributing and

staring solar produced H2 gas

Solar cells & solar thermal systems still two

costly.

Solar energy:

1. Passive solar heating system.

2. Active Solar heating system.

3. Passive solar heating system – absorbs and stores heat from the sun directly within a structures.

4. Active solar heating system collectors absorb solar energy and a fan or a pump supplies part of

building space heating or water heating needs.

Passive SHS

Energy efficient windows and attached green houses face the sun to collect solar energy by direct

gain walls and floors of concrete, brick, store, water in metal or plastic container store much of the

collected solar energy as heat and release it slowly through out the day and night.

Active SHS:

Several connected collectors are usually mounted on the roof with an unobstructed exposure to the

sun some of heat can be used directly. The rest can be stored in insulated tanks containing rocks, water or

a heat absorbing chemical for release needed. It can also supply hot water.




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Passive or Active Solar heating


Energy is free Need access to sun 60 % of time.

Net energy is moderate (active ) to high

(passive

Blockage of sun access by other structures.

Quick Installation Need heat storage system.

No CO2 emission High cost

Very low air & water Pollution Active system needs maintenance and repair

Very low land disturbance (built into roof or

window)

Active collectors unattractive.

Moderate cost ( Passive)

Solar energy to generate high temperature, heat and electricity

Solar thermal systems collect and transform radiant energy from the sun into high temperature thermal

energy, which can be used directly or converted to electricity.

1. Central receiver system – Power tower

Huge arrays of computer controlled mirrors called heliostats track the sun & focus sunlight on a

central heat collection tower.

2. Distributed receiver system, in which sunlight is collected and focused on oil filled pipes running

through the middle of curved solar collectors. This concentrated sunlight can generate temperature




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high enough for industrial process or for producing steam to run turbines and generate electricity.

3. A different type of distributed receiver system uses parabolic dish collectors instead of troughs. These

collectors can track sun along two axes and are more efficient than troughs.

Solar cookers:

Concentrate sunlight and cook food. They can be made by fitting an insulated box big enough to

hold three or four pots with a transparent, removable top.

Solar energy for high temperature heat and electricity


Moderate net energy Low efficiency

Moderate environmental impact High cost

No CO2 emission Needs backup or storage system

Fast construction High land use

Cost reduced with natural gas turbine backup May disturb desert areas.

Solar Cells:

Solar energy can be converted directly into electrical energy by photovoltaic cells (PV cells) solar

cells. It is a transparent wafer containing a semi conductor material. Sunlight energizer and causes an

electron in the semi conductor to flow creating a current. A single cell produces only tiny amount of

energy. Thus many cells are wired together in modular panels to produce the amount of electricity

needed.

Large scale hydro power:

High dam is built across large river to create a reservoir. Some of the water stored in the




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reservoir is allowed to flow through huge pipes at controlled rates, spinning turbines and producing

electricity.

Small scale hydro power:

Low dam with no reservoir is built across a small stream and the streams flow of water is used to

spin turbines and produce electricity.

Tidal energy:

Twice a day in high and low tides, water that flows into and out of coastal bays and estuaries can

spin turbines to produce electricity.

Wave energy:

The kinetic energy in Ocean waves created primarily by wind is another potential source of

electricity.

Ocean Thermal energy conversion

The large temperature difference between the cold water and sun warmed surface water of tropical

oceans are used for producing electricity.




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Wind Energy:

The high speed winds have lot of energy in them as KE due to their motion. The driving force of

the wind is sum. It is harnessed by wind mills.

The blades of windmill keep on rotating continuously due to the force of the striking wind. The

rotational motor of blade drives a number of machines like water pumps, flour mills and generator. Ideal

location is coastal region, open grass lands or hilly regions, particularly mountain passes where the winds

are strong and steady.

The wind power potential in our country is estimated to be 20000 MW, while at present we are

generating of about 1020 MW.

Geo thermal energy:

Heat contained in underground rocks & fluid is a source of energy.

Geothermal energy from earth’s mantle has been transferred to three types of underground reservoirs.

1. Dry steam which consists of steam with no water droplets

2. Wet stream consists of a mixture of steam & H2Odroplets.

3. Hot water trapped in fractured or porous rock at various places in the earth’s crust. If such sites are close to surface, wells can be drilled to extract the dry / wet stream or hot water.

This energy can be used to heat homes buildings and to produce electricity.




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Hydrogen fuel:

When H2 burns in air, it combines with O2 gas in the air and produces non polluting H2O

2H2 +O2 2H2O

Wide spread use of this fuel would eliminate most of air pollution problem.

It reduces the threat from global warming by enacting noCO2

H2 is produced by electrolysis of water

H2 is produced in high temperature or by chemical processes.

Photolysis of Water:

Decomposition of sewage and wet bio mass produce H2.

Energy from Biomass:

Biomass consists of plant materials and animal wastes used as sources of energy.

It can be burned directly as a solid fuel or converted into gaseous or liquid biofuels.

- One way to produce biomass fuel is to plant, harvest and burn large numbers of fast

growing trees (Cotton wood, poplar, willows, leucaenas) (biomass plantation)

- In agricultural areas, crop residues and animal manure can be collected and burned or

converted to biofuels.

Bio gas

Mixture of 60% CH4, & 40% CO2

Bacteria and various chemical processes can convert some forms of biomass into gaseous and

liquid biofuels.




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Biogas digesters convert plant and animal wastes into methane fuel for heating and cooking.

These simple devices can be built for about $ 50 including labour.

After biogas has been separated, solid residue is used as fertilizer.

Ethanol can be made from sugar and grain crops by fermentation and distillation.

Methanol is produced from wood, wood wastes agricultural wastes, sewage, garbage and coal.

LAND RESOURCES

Land as a Resource:

Land is a finite and valuable resource upon which we depend for our food, fibre and fuel wood,

the basic amenities of life. Soil, especially the top soil, is classified as renewable resources because it is

continuously regenerated by natural process through at a very slow rate. About 200 – 1000 years are

needed for the formation of one inch or 2.5 cm soil, depending upon the climate and the soil type. But,

when rate of erosion is faster than rate of renewal, then the soil becomes a non renewable resource.

Land Degradation:

With increasing population growth the demands for arable land for producing food, fibers and

fuel wood is also increasing. Hence, there is more and more pressure on the limited land

resources which are getting degraded due to over – exploitation. Soil degradation is a real

cause of alarm because soil formation is an extremely slow process as discussed above and the

average annual erosion rate is 20 – 100 times more than the renewal rate.

Factors responsible for land degradation:

1.Soil Erosion:

The literal meaning of ‘soil erosion’ is wearing away of soil. Soil erosion is defined as the

movement of soil components, especially surface – litter and top soil from one place to another soil




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erosion results in the loss of fertility because it is the top soil layer which is fertile.

2. Soil pollution:

Application of chemicals in the form of fertilizers, pesticides, herbicides and insecticides into the

field for getting more agricultural production creates soil pollution.

3. Salinization and water logging

Poor irrigation practices saturate land with salts and reduce the fertility. Excessive usage of water

for agriculture and flooding create water logging problems.

4. Shifting cultivation:

In the recent time, due to exploding population, more and more agricultural land is being

sacrificed for housing. This poses great threat to soil fertility and food production.

5. Desertification:

Soil erosion creates infertility of soil and leads to loss in soil productivity and formation of deserts.

6. Urbanization:

Because of urbanization, grasslands, croplands and forests are affected. Fertile and productive

land deteriorates due to developmental activities such as human settlement, industries, roads, railways,

airports, dams etc.

7. Continuous irrigation:

Sowing crops without fertilizers season after season drains the soil of its lifeblood nutrients.

Methods of Controlling land degradation:

Afforestation: Controls the land degradation

Reforestation: Replanting forests at places where they were destroyed by overgrazing,

excessive felling, forest fires, etc.

Desertification can be checked by planting several rows of trees at right angles to the

prevailing wind direction

Better agricultural practices.

1) Terracing: The sloppy agricultural drainage land can be divided into a number of small

distinct fields.

2) Regular cultivation: To reduce land degradation the fields should not be left bare and there

should be regular cultivation.

3) Rotation of Crop: Sowing of different crops in the same field in the regular sequence for a

number of years.

4) Fallowing: Ploughing the field extensively and then leaving them without sowing for a

year or two by this way, aeration, texture and fertility of soil can be improved

Man induced landslides:

Movement of earthy material from higher region to lower region through a certain plane is called

lands lids.

The occurrence of lands slide is particularly common in geodynamically sensitive belts, the

mountain regions.




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Following human activities induces the land slide

Cutting and deep excavations on slopes for buildings, roads, canals and mining activities

trigger mass – movement.

The addition on the slopes like dumping of debris or wastes and the construction of heavy

structures increase the chances of landslides.

Due to transport movements in the unstable sloppy regions, landslides occur.

Underground mining activities may cause subsidence of the ground.

Removing of vegetation in the sloppy area creates soil erosion and leads to landslides.

Soil Erosion:

Loss or removal of the superficial layer of the soil by the action of water, wind by the activities of

man is termed as soil erosion.

Causes of soil erosion:

The mountain ranges are prone to erosion caused by heavy rains that strip topsoil from steep slopes.

Grazing of cattle over vegetal carpet not only damages the forest, but the soil as well.

Deforestation is another reason by which the soil gets eroded easily.

Land slide produces soil erosion.

Wind erosion, carrying away finer particles and creates soil erosion.

Because of the tidal and wave action, varying degrees of erosion is taking place along the coastal regions.

The construction of roads disturbs the stability of the hillside, removes the protective vegetal cover and

leads to soil erosion.

Controlling measures of soil erosion:

It is very important to prepare erodibility maps to control soil erosion.

Soil loss can be avoided by covering the watershed with vegetation.

Soil conservation can be achieved by constructing a series of check dams in the watershed

area.

Channel beds and sides can be protected by introducing vegetation.

In deserts, the movement of the sand can be effectively arrested by building wind breakers.

Further application of chemicals, asphalt and rubber solutions stabilize the surface of the

dunes.

Along the coasts, groynes have proved very effective in controlling erosion and building up

beaches.

Fetties are massive structures, constructed along the channels of estuaries and lagoons for

retarding erosion.

Desertification:

The loss of productivity of soil as a consequence of degradation or pervasive dryness called

Desertification.

Climate is one of the most important factor in the development of desertic conditions the abuse of




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land and over – exploitation of vegetal and water resources are primarily responsible for the expansion of

desert of aggravation of desertic conditions Measures to combat desertification.

1. Desertification hazard map:

The first step in this process is the preparation of a desertification hazard map.

2. Change in grazing practices:

Livestock should not be allowed to graze freely. The cattle should be protected but

permitted to graze only in the specially fenced reserves.

3. Stabilizing active dunes:

To prevent wind erosion a cover of grasses, shrubs and trees having deep roots may be grown

4. Construction of wind breaks or shelters – belts in the wind ward side of the settlements and

agricultural farms reduce the velocity of winds and check the advancement of the dunes.

5. Spray of asphalt mulch and spread of jute nettings on the dunes is another protective measure for

desertification.

6. The practice of Rain water Harvesting is useful solution for water scarcity problem in desert

regions.

Consequences of Desertification:

Reduction of agricultural land, cattle and vegetal productivity

Loss of fertility and causes soil salinity.

Uncontrolled water losses by evaporation.

Worsens drought and famine

Economic Losses.

Creates lower living standard of the people and environmental refuges.

CONSERVATION NATURAL RESOURCES; ROLE OF AN INDIVINDUAL

Different natural resources like forests, water, soil food, mineral and energy resources play a vital

role in the development of a nation. However, overuse of these resources in our modern society is

resulting in fast depletion of these resources and several related problems. If we want our mankind to

flourish there is a strong need to conserve these natural resources.

Environment belongs to each one of us and all of us have a responsibility to contribute towards its

conservation and protection. With our small individual efforts we can together help in conserving our

natural resources to a large extent. Let us see how individuals can help in conservation of different

resources.

CONSERVE WATER:

Don’t keep water taps running while brushing, saving washing or bathing. In washing machines fill the machine only to the level required for your clothes.

Install water saving toilets (6 litres per flush)

Check for water leaks and repair etc.

Re use the soapy water of washings from clothes for washing off courtyards, drive ways etc.

Water the plants in evening when evaporation losses are minimum.




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Use drip and sprinkling irrigation to improve its efficiency and reduce evaporation.

Install a small system to capture rain water and collect normally wasted used water from sinks,

clothe – washers, bath tubs etc which can be used for watering the plants.

Build Rain water harvesting system.

PROTECT THE SOIL:

While constructing house, don’t uproot the trees as far as possible. Plant disturbed areas with fast growing native covers.

Grow grass in open area which will bind the soil and prevent its erosion.

Donor irrigate the plants using a strong flow of water as it would wash off the soil

Better use sprinkling irrigation.

Use green manure and mulch in the garden and kitchen garden which will protect the soil.

Use mixed cropping so that specific soil nutrients do not get depleted.

Do not over irrigate your fields without proper drainage to prevent water logging and salinisation.

PROMOTE SUSTAINABLE AGRICULTURE

Do not waste food. Take as much as you can eat.

Reduce the use of pesticides

Fertilize the soil with organic fertilizers

Use drip irrigation.

Eat local & Seasonable vegetation. This saves tot of energy on transport storage and preservation.

Control pests by a combination of cultivation and biological control methods.

Do not use endangered species products

RESPONSIBLE CONSUMERISM:

Practice living simply

Recycle or Reuse the materials

Encourage ecofriendly products

Buy organic food

Buy locally grown and made item

Invest green business.

Before buying costly items think twice environmental impacts and yours need.

CONSERVE ENERGY:

Use stair instead of elevators

Use public transportation, walk or ride a bicycle.

Turn off lights, fans and other appliances when not in use

Use solar cooker, solar heater,

Plants trees around the building to make Cool so that it will cut off your electricity charges.

Add more insulation to your house

Recycle and Reuse, glass, metals and paper

Buy always locally made long testing materials.




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REDUCING WASTE:

Buy foods that come with less packaging

Take some container / bag from home to market for purchase.

Better to take your own washable, refillable beverage containers to meetings and functions.

Prefer to buy item which can be recyclable / revisable

Buy environmentally degradable products.

Separate at source the plastic papers, glass for recycling.

Compost all garden wastes & Vegetable wastes.

Support government, which will be interested in environmental conservation.

LOWERING YOUR FOREST IMPACTS

Reuse & Recycle paper

Make double sided copies

Use email

Avoid using timber and plywood

Encourage sustainably harvested wood.

Encourage minor forest produce items on which tribal people depend.




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UNIT-IV

SOCIAL ISSUES AND THE ENVIRONMENT

From unsustainable to sustainable development:

Brundland commission describes sustainable development as the development that meet needs of present generation without compromising ability of future generations to meet their own need Concept of sustainable development A symbiotic relationship between consumer human race and producer natural system

Compatibility between ecology and economics

Aim of sustainable development: Inter generational equity

Intra generational technology

Significance of sustainable development: Developing appropriate technology

Reduce , reuse, recycle of natural resources

Providing environmental education and awareness

Consumption of renewable resources

Conservation of nonrenewable resources

Population control

Urban problems related to energy: Urbanization: Movement of human population from rural areas top urban areas for betterment of education, communication, health, employment etc Causes; Cities are main centers of economic growth, trade, transportation, education, medical facilities and employment Urban sprawl: Urban growth is fast , so difficult to accommodate with their limited area .So cities spread into rural areas Urban energy requirement:

Residential and commercial lighting

Public and private transportation

Electrical and electronic appliances




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Solution: Use public transport instead of motor cycles Energy consumption must be minimized Use solar and wind energy Impose strict laws, penalty, and energy audit Water conservation: Process of saving water for future utilization Water source: Fresh water

River

Stream

Pond

Ocean

Need for water conservation: Population increases water requirement also increases

Due to deforestation annual rainfall decreases

Over exploitation of ground water

Ways of water conservation Reducing evaporation loss

Reducing irrigation loss

Reuse water

Avoid sewage discharge Water conservation method

Rain water harvesting

Watershed management

Rain water harvesting Objective: To meet increasing demands of water Raise water table by recharging ground water Reduce ground water contamination from salt water intrusion Roof top rainwater harvesting




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Involves collecting water that falls on roof of house

Rainwater from roof top, road surface, play ground diverted to surface tank Advantages of rainwater harvesting

Increases the well water availability

Raise ground water level

Minimizes soil erosion

Watershed management: It is defined as land area bounded by divide line from which water drains under influence of gravity in to stream, lakes, reservoir. Eg. Pits, dams, Farm, ponds, Himalaya. Types

1. Micro 2. Mini 3. Macro Watershed

Management; The management of rainfall & resultant runoff.

Forestry

Halt deforestation, provide vegetative cover, degraded land and supplement folder and fuel wood resources available to rural communities Agriculture

- Aims to increase agricultural productivity in sustained manner and to diversify crop production - Major objective shall be achieved through organizing farmers, training camps and exposure visits. - Construct check dams, water harvesting tanks, storage tanks and channels , repair of old

channels , implementing measures to check soil erosion Horticulture establishment of private orchard

Rejuvenation of existing orchards

Distribution of horticulture plant for home garden planting.

Animal husbandry

Energy conservation

Community participation

Training and awareness programme

Advantages of Watershed projects

- Improved access to drinking water in project areas during drought - Increase in cultivation area leading to increase in employment




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- Increase in crop yield, resulting better income to rural population - Improved availability of fodder for animals and increase in milk yield - Increase in employment & involvement of women - Increase in net returns from all crops. - Decrease in soil erosion. - Restoration of ecological balance.

Resettlement and Rehabilitation of people: Resettlement – simple relocation or displacement of human population. Rehabilitation – making, system to work again by allowing, system to function naturally. Includes replacing the lost economic assets, Safeguard Employment, Provide safe land for building Repair damaged infrastructure.

Effects: Loss of land

Loss of recourse

Unsatisfactory comp[enasation

Social and cultura problems

Changes in tradition of indigenous people

Spread of disease

Submergence of valuable forest

Waterlogging

Extinction of wild life

Environmental ethics:-

Over exploitation of forests, land, water as well as various living components of biosphere and failure to tackle the problem of pollution and environmental degradation are exposing the humanly to the thread of a global environment crisis.

It emphasis that real development cannot occur unless the strategies which are formulated are

implemented are environmentally sustainable. Even though our government is formulating several rules, regulations, policies, laws, it is the duty of each and every one to protect our nature.

Therefore human beings are ethically responsible for the preservation of the world‟s ecological

integrity. The environment ethics literally means conscious efforts to protect environment and to maintain its stability from the pollutants. Following are some of the ways to safeguard environment.

1. To sacrifice the consumption of some of the good which reduces environment quality 2. Minimize the resource utilization and conservation 3. Adopt sustainable and eco friendly development. (e.g) reduction of waste, recycling, waste

management and harvesting non conventional energy If we change as individuals then the society will also change by itself. The society is nothing bu




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an extension of the individual. CLIMATE CHANGE

Context - The Earth's climate has changed over the last century and by 2001 there was strong evidence

that most of the warming observed the previous 50 years was attributable to human activities.

Moreover, computer models already predicted that temperatures would continue to rise over the 21st

century.

This was revealed by the Third Assessment Report of the Intergovernmental Panel on Climate Change

(Daphnia) which involved many hundreds of scientists from many countries.

An increasing number of observations indicates that the world has warmed:

Variations of the Earth’s surface temperature over the last 140 years.

Variations of the Earth’s surface temperature over the last 1000 years. The average surface temperature has increased over the 20th century by about 0.6C (± 0.2°C). This

increase occurred mainly from 1910 to 1945 and 1976 to 2000. The increase is larger at night time and

over land area.

It is likely that in the Northern Hemisphere, over the past 1000 years:

the temperature increase in 20th century was the largest,

the 1990s was the warmest decade and 1998 the warmest year.

Temperatures have risen during the past four decades in the lowest 8 kilometers of the atmosphere.

Snow cover and ice extent have decreased.

The sea level has risen by 10 to 20 cm (4 to 8") during the 20th century. Ocean temperature has

increased since the late 1950s

CLIMATE CHANGE OBSERVED

Precipitation is likely to have increased in the 20th century in some land areas and decreased in

others.

It is likely that there has been some increase in cloud cover.



http://www.greenfacts.org/glossary/def/daphnia.htm

http://www.greenfacts.org/en/climate-change-ar3/toolboxes/figspm-1as.htm#a1









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It is very likely that there has been less extreme low temperatures and slightly more extreme high

temperatures.

There have been more warm episodes of the El Niño since the mid-1970s.

There were relatively small global increases in severe drought or severe wetness over the century

but an increase in droughts in some regions in recent decades.

The following aspects of our climate have NOT changed.

No warming is apparent in some parts of the Southern Hemisphere oceans and parts of Antarctica.

No systematic rainfall change over the Southern Hemisphere.

No significant trends of Antarctic sea-ice extent.

No clear change in tropical and extra-tropical storm intensity and frequency or in the frequency of

tornadoes, thunder days, or hail events.

CAUSES OF CLIMATE CHANGE

Changes in climate are the result of both internal variability within the climate system and external factors

(both natural and anthropogenic).Human emissions are significantly modifying the concentrations of

some gases in the atmosphere. Some of these gases are expected to affect the climate by changing the

earth's radiative balance, measured in terms of radiative forcing.

Greenhouse gases, which have a global effect, tend to warm the earth surface by absorbing some of the

infrared radiation it emits.

The principal anthropogenic greenhouse gas is carbon dioxide (CO2), whose concentration has

increased by 31% since 1750 to a level which is likely to have not been exceeded for 20 million

years. This increase is predominantly due to fossil fuel burning, but also to land-use change,

especially deforestation.

The other significant anthropogenic greenhouse gases are methane (CH4) (151% increases since

1750, 1/3 of CO2's radiative forcing), halocarbons such as CFCs and their substitutes (100%

anthropogenic, 1/4 of CO2's radiative forcing) and nitrous oxide (N2O) (17% increases since 1750,

1/10 of CO2's radiative forcing).

Anthropogenic aerosols, which have a regional effect, are short-lived and mostly tend to cool the earth

down. Known natural factors such as changes in solar irradiance and volcanic eruptions are expected to

have only made small contributions to radiative forcing over the past century.

Although more research is needed, understanding of climate processes and computer models have

improved (More...), leading the IPCC to draw the following conclusion

Most of the warming over the last 50 years is likely to have been due to man-made activities.

CONSEQUENCES OF CLIMATE CHANGE

Regional changes in climate, particularly increases in temperature, have already affected some physical

and biological systems.

Both natural and human systems are vulnerable to climate change because of their limited adaptive

capacity. This vulnerability varies with geographic location, time, and social, economic and

environmental conditions.

Some extreme weather events and the damage, hardship, and death they cause are projected to increase




95

with global warming. There is also a potential for large-scale and possibly irreversible impacts which pose

risks that have yet to be reliably quantified; their likelihood is probably very low but is expected to

increase with the rate, magnitude, and duration of climate change.

Man will have to adapt to and cope with the climate change consequences that are not prevented by

mitigation. Economic losses can be expected, especially in poorest regions; the higher the warming, the

greater the losses. Promoting adaptation, sustainable development and equity can be mutually reinforcing.

EFFECTS OF CLIMATE CHANGE IN THE FUTURE

Projected changes in climate are expected to have both beneficial and adverse effects on water resources,

agriculture, natural ecosystems and human health. But the larger the changes in climate the more the

adverse effects should dominate.

For instance, some crop and forest productivities could benefit from a small climate change. But for many

other natural systems, the adverse effects should be dominant, especially if warming exceeds a few

degrees.

Human populations are expected to face increasing flooding and heat waves but reduced cold spells. The

geographic range for infectious diseases should increase

The vulnerability of human populations and natural systems to climate change differs substantially across

regions and across populations within regions.

CONTROL OF GREENHOUSE GAS EMISSIONS

Climate change is a unique, global, long-term problem, involving complex interactions.

There are many technological options for reducing greenhouse gas emissions, some at low or negative

cost. Forests and agricultural lands provide significant but not necessarily permanent carbon sinks, which

may allow time for other options.

There will be both costs and benefits to reducing greenhouse gases. Most studies project that in 2010, the

Kyoto Protocol should cost developed countries a reduction in projected GDP of about 0.2% to 2%

without emission trading and about half of that with emission trading. Greenhouse gas reduction programs

need to overcome many barriers. Governments have a wide array of instruments at their disposal. With

coordinated actions and international regimes, efficiency and equity should improve. Further research is

required to strengthen future assessments and to reduce uncertainties.

ECOSYSTEMS AND CLIMATE CHANGE

Ecosystems have a limited capacity to adapt to climate change; some might not be able to cope as they

had done in earlier periods and are expected to suffer damages because:

The rate and extent of climate change is expected to be faster and greater than in the past and

could exceed nature's maximum adaptation speed;

Human activities and pollution have increased the vulnerability of ecosystems.

The earth's climate has changed over the last century. There is new and stronger evidence that most of the

warming observed the last 50 years is attributable to human activities. Evolving computer models are

predicting that, because of greenhouse gas emissions, temperatures should continue to rise over the 21st

century), impacting nature and mankind both positively and negatively.

The impacts should vary among regions, but they can not yet be predicted accurately, especially for small-




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scale areas. However, it is expected that:

1. the more the greenhouse gases are emitted, the higher the tendency for the earth to warm

2. the greater and faster the warming, the more the adverse effects will dominate,

3. and the higher the possibility, although probably remote, of large-scale and possibly irreversible

impacts.

Therefore, although an acceptable level for greenhouse gases has not yet been determined, reducing

emissions should reduce the risk of adverse effects. Many options for emission reductions are available

;their costs need to be balanced with the risks left for future generations.

GLOBAL WARMING

Global warming is the increase in the average temperature of the Earth's near-surface air and oceans

since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ±

0.18 °C (1.33 ± 0.32 °F) during the last century. The Intergovernmental Panel on Climate Change (IPCC)

concludes that increasing greenhouse gas concentrations resulting from human activity such as fossil fuel

burning and deforestation caused most of the observed temperature increase since the middle of the 20th

century. The IPCC also concludes that variations in natural phenomena such as solar radiation and

volcanoes produced most of the warming from pre-industrial times to 1950 and had a small cooling effect

afterward. These basic conclusions have been endorsed by more than 40 scientific societies and

academies of science, including all of the national academies of science of the major industrialized

countries. A small number of scientists dispute the consensus view.

Climate model projections summarized in the latest IPCC report indicate that the global surface

temperature will probably rise a further 1.1 to 6.4 °C (2.0 to 11.5 °F) during the twenty-first century.

GREEN HOUSE EFFECT

Life on earth depends on energy from the sun. About 30 percent of the sunlight that beams toward Earth is

deflected by the outer atmosphere and scattered back into space. The rest reaches the planet’s surface and is reflected upward again as a type of slow-moving energy called infrared radiation.

As it rises, infrared radiation is absorbed by “greenhouse gases” such as water vapor, carbon dioxide, ozone and methane, which slows its escape from the atmosphere.

Although greenhouse gases make up only about 1 percent of the Earth’s atmosphere, they regulate our climate by trapping heat and holding it in a kind of warm-air blanket that surrounds the planet.

This phenomenon is what scientists call the "greenhouse effect." Without it, scientists estimate that the

average temperature on Earth would be colder by approximately 30 degrees Celsius (54 degrees

Fahrenheit), far too cold to sustain our current ecosystem.

While the greenhouse effect is an essential environmental prerequisite for life on Earth, there really can be

too much of a good thing.

The problems begin when human activities distort and accelerate the natural process by creating more

greenhouse gases in the atmosphere than are necessary to warm the planet to an ideal temperature.

Burning natural gas, coal and oil —including gasoline for automobile engines—raises the level

of carbon dioxide in the atmosphere.

Some farming practices and land-use changes increase the levels of methane and nitrous oxide.

Many factories produce long-lasting industrial gases that do not occur naturally, yet contribute



http://en.wikipedia.org/wiki/Instrumental_temperature_record

http://en.wikipedia.org/wiki/Celsius

http://en.wikipedia.org/wiki/Fahrenheit

http://en.wikipedia.org/wiki/Intergovernmental_Panel_on_Climate_Change

http://en.wikipedia.org/wiki/Greenhouse_gas

http://en.wikipedia.org/wiki/Anthropogenic

http://en.wikipedia.org/wiki/Fossil_fuel

http://en.wikipedia.org/wiki/Deforestation

http://en.wikipedia.org/wiki/Attribution_of_recent_climate_change

http://en.wikipedia.org/wiki/Solar_variation

http://en.wikipedia.org/wiki/Volcano

http://en.wikipedia.org/wiki/Pre-industrial

http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change

http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change

http://en.wikipedia.org/wiki/National_academy

http://en.wikipedia.org/wiki/G8

http://en.wikipedia.org/wiki/G8

http://en.wikipedia.org/wiki/List_of_scientists_opposing_the_mainstream_scientific_assessment_of_global_warming

http://en.wikipedia.org/wiki/Climate_model

http://en.wikipedia.org/wiki/Global


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significantly to the enhanced greenhouse effect and “global warming” that is currently under way. Deforestation also contributes to global warming. Trees use carbon dioxide and give off oxygen

in its place, which helps to create the optimal balance of gases in the atmosphere. As more forests

are logged for timber or cut down to make way for farming, however, there are fewer trees to

perform this critical function.

Population growth is another factor in global warming, because as more people use fossil fuels

for heat, transportation and manufacturing the level of greenhouse gases continues to increase. As

more farming occurs to feed millions of new people, more greenhouse gases enter the atmosphere.

Ultimately, more greenhouse gases means more infrared radiation trapped and held, which gradually

increases the temperature of the Earth’s surface and the air in the lower atmosphere. The Average Global Temperature is Increasing Quickly

Today, the increase in the Earth’s temperature is increasing with unprecedented speed. To understand just how quickly global warming is accelerating, consider this:

During the entire 20th century, the average global temperature increased by about 0.6 degrees Celsius

(slightly more than 1 degree Fahrenheit).

Using computer climate models, scientists estimate that by the year 2100 the average global temperature

will increase by 1.4 degrees to 5.8 degrees Celsius (approximately 2.5 degrees to 10.5 degrees

Fahrenheit).



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Greenhouse gases:

Many chemical compounds present in Earth's atmosphere behave as 'greenhouse gases'. These are gases

which allow direct sunlight (relative shortwave energy) to reach the Earth's surface unimpeded. As the

shortwave energy (that in the visible and ultraviolet portion of the spectra) heats the surface, longer-

wave (infrared) energy (heat) is reradiated to the atmosphere. Greenhouse gases absorb this energy,

thereby allowing less heat to escape back to space, and 'trapping' it in the lower atmosphere. Many

greenhouse gases occur naturally in the Atmosphere, such as carbon dioxide, methane, water vapor, and

nitrous oxide, while others are synthetic. Those that are man-made include the chlorofluorocarbons

(CFCs), hydro fluorocarbons (HFCs) and Per fluorocarbons (PFCs), as well as sulfur hexafluoride

(SF6). Atmospheric concentrations of both the natural and man-made gases have been rising over the

last few centuries due to the industrial revolution. As the global population has increased and our

reliance on fossil fuels (such as coal, oil and natural gas) has been firmly solidified, so emissions of

these gases have risen.

Causes of Global Warming

1. Carbon Dioxide from Power Plants

Coal emits around 1.7 times as much carbon per unit of energy when burned as does natural gas and 1.25

times as much as oil. Natural gas gives off 50% of the carbon dioxide, the principal greenhouse gas,

released by coal. Coal contains about 80 percent more carbon per unit of energy than gas does, and oil

contains about 40 percent more.

2. Carbon Dioxide Emitted from Cars

Vehicles with poor gas mileage contribute the most to global warming. For each gallon of gas a vehicle

consumes, 19.6 pounds of carbon dioxide are emitted into the air.

If car manufacturers were to increase their fleets' average gas mileage about 3 miles per gallon, this

country could save a million barrels of oil every day, while US drivers would save $25 billion in fuel

costs annually.

3. Carbon Dioxide from Airplanes

The UN's Intergovernmental Panel on Climate Change estimates that aviation causes 3.5 percent of global

warming, and that the figure could rise to 15 percent by 2050.

4. Carbon Dioxide from Buildings

Buildings structure account for about 12% of carbon dioxide emissions.

5. Methane

While carbon dioxide is the principal greenhouse gas, methane is second most important. According to

the IPCC, Methane is more than 20 times as

effective as CO2 at trapping heat in the atmosphere.

6. Water Vapor in the Atmosphere Increasing

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presence is the result of warming caused by carbon dioxide, methane and other greenhouse gases. Water

vapor holds onto two-thirds of the heat trapped by all the greenhouse gases. As the Earth heats up relative

humidity is able to increase, allowing the planet's atmosphere to hold more water vapor, causing even

more warming.

7. Nitrous oxide

Another greenhouse gas is Nitrous oxide (N2O), a colourless, non-flammable gas with a sweetish odour,

commonly known as "laughing gas", and sometimes used as an anaesthetic. Nitrous oxide is naturally

produced by oceans and rainforests. Man-made sources of nitrous oxide include nylon and nitric acid

production, the use of fertilisers in agriculture, cars with catalytic converters and the burning of organic

matter.

8. Deforestation

After carbon emissions caused by humans, deforestation is the second principle cause of atmospheric

carbon dioxide. Deforestation is responsible for 20-25% of all carbon emissions entering the atmosphere,

by the burning and cutting of about 34 million acres of trees each year.

9. Permafrost

Permafrost is a solid structure of frozen soil, extending to depths of 2.200 feet in some areas of the arctic

and subarctic regions, containing grasses, roots, sticks, much of it dating back to 30,000 years. About

25% of the land areas of the Northern Hemisphere hold permafrost, which is defined as soil whose

temperature has been 32 degrees Fahrenheit (0 degrees Celsius) for a period of at least 2 years. Permafrost

is under 85% of Alaska land surface and much of Canada, Scandinavia and Siberia and holds about 14 per

cent of the world's carbon.

Present Danger of Global Warming

As the eagle was killed by the arrow winged with his own feather, so the hand of the world is wounded by

its own skill. -Helen Keller

Deaths due to climate change

Increasing Storms and Floods

Weather-Related Natural Disasters

Killer Heat Waves

Islands are Endangered by Rising Seas

Coral Bleaching

The Trend to Dead Zones in Oceans

Decline in Antarctic Krill

Severe Diseases Caused by Climate Change

Forest's Enemy, Beetles

Threat to Animals

Coastal Flooding

Wildfires Increasing

Warming Ocean Waters Kills Plankton

The Danger to Birds

Australia may be facing a permanent drought



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Besides global warming, here's what fossil fuel dependency gives us

1. Deaths Due to Climate Change

A study, by scientists at the World Health Organization (WHO) determined that 154,000 people die every

year from the effects of global warming, from malaria to malnutrition, children in developing nations

seemingly the most vulnerable. These numbers could almost double by 2020.

2. Increasing Storms and Floods

Global warming has produced an increase in precipitation during the 20th century, mostly in the form of

heavy rainstorms, little in moderate, beneficial rainstorms.

Scientists are saying that global warming is causing early snowmelts.

3. Weather-Related Natural Disasters

On November 28, 1998 the San Francisco Chronicle ran an Associated Press article reporting that dollar

damages from weather-related natural disasters (floods, storms, droughts, fires) worldwide for 1998

totaled $89 billion. Total damages for the entire decade of the 1980's were $83 billion

4. Killer Heat Waves

In June, 2003, 1700 people died during a heat wave that hit India, while 35,000 Europeans died in a heat

wave the following August.

5. Islands are Endangered by Rising Seas

Many islands and beaches are in danger of flooding all over the world.

The island state of Kiribati (population, 75,000) is being threatened with rising seas, engulfing

homes and crops. These are rising sea levels, surges during sunny weather. Says one islander, "It's

nice weather, and all of a sudden water is pouring into your living room."

6. Coral Bleaching

Although coral reefs cover less than 0.2% of the ocean's area, they contain 25% of marine fish species.

An example of coral reef biodiversity are the reefs of the Florida Keys, which sustain 500 species of fish,

more than 1700 species of mollusks, five species of sea turtles, and hundreds of species of sponges.

Coral bleaching is happening all over the world in many countries. Whenever coral is stressed by higher

water temperatures, even only 2 or 3 degrees Fahrenheit warmer, it may expel the algae that nourishes it

and gives the coral its color, thus coral bleaching. Coral usually recovers from bleaching, but it cannot

survive the stress of constant warming waters.

7. The Trend to Dead Zones in Oceans

In a study released February 15, 2008 researchers noted that coastal waters are showing dead zones,

extending from the state of Washington down to California. The reason for the areas of depleted oxygen is

the persistent, strong winds that are pushing surface waters. The unusually strong winds promote the

growth of plankton and hold low-oxygen water on the continental shelf for longer periods.

8. Decline in Populations of Antarctic Krill

Because of increasing temperatures, areas of sea ice in the Antarctic Peninsula region have diminished

significantly. And the algae that grows on the underside of the shrinking sea ice is therefore also

diminishing. The algae is a food source of krill, which is also disappearing in antarctic waters. Scientists

report a tenfold decline in krill populations during the past 10 years.



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9. Severe Diseases Caused by Climate Change

A recent study by New Zealand doctors, researchers at the Wellington School of Medicine's public health

department said outbreaks of dengue fever in South Pacific islands are directly related to global warming.

"Many of the most important diseases in poor countries, from malaria to diarrhoea and malnutrition are

highly sensitive to climate," said Diarmid Campbell-Lendrum, of the World Health Organization (WHO),

and a co-author of a report published in the science journal Nature on November 17, 2005. The report

says that climate change is the driving force behind an increase in debilitating illnesses such as malaria,

malnutrition and diarrhea.

10. Threat to Animals

Habitats of many wildlife animals are threatened due to change in the temperature.

Polar Bear-Temperatures in the Antarctic and Arctic has increased significantly to the point that sea ice

has diminished in the both regions. In the Arctic this has meant a decreased habitat for the polar bear.

11. Coastal Flooding

Global warming is melting ice to the tune of 50 billion tons of water a year from the Greenland ice sheet.

A NASA high-tech aerial survey shows that more than 11 cubic miles of ice is disappearing from the ice

sheet annually. This is increasing the likelihood of coastal flooding around the world, if this meltdown

trend continues.

12. Wildfires Increasing

The forests of Canada, Alaska and the former Soviet Union including Siberia are apparently burning like

never beforeThe likely reason: Global warming is drying out northern timber and brush. As a result,

lightning bolts spark infernos of colossal extent.

FUTURE THREAT OF GLOBAL WARMING

"Global warming is real; the risks it poses are real; and the American people have a right to know it and a

responsibility to do something about it. The sooner Congress understands that, the sooner we can protect

our nation--and our planet--from increased flood, fire, drought, and deadly heat waves." President Bill

Clinton, July 25, 1998. (Quotation from transcript of President Clinton’s radio address of July 25, 1998) Deaths Due to Global Warming

1. The Threat of Mass Extinction

2. Species Threatened by Climate Change

3. Coral Bleaching & Disintegration

4. The Trend to Dead Zones in Oceans

5. Floods

6. More Intense Hurricanes on the Way

7. Heat Waves

8. Increasing Power Outages

9. Forests and Wildfires

10. Global Warming, Forests & Bark Beetles

11. Threat to Boreal Forests

12. Sea Level Rise & Climate Change Refugees

13. Sea Level Rise & Impact on US Cities

14. Coastal Wetlands



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15. Spread of Infectious Diseases

16. Escalating Increase in Allergens

17. Global Warming And Asthma

18. Loss of Arctic Sea Ice

19. Weather-Related Damage

20. Disappearing Beaches

21. Damage & Loss of World's Ecosystems & Biomes

22. Effect on Stratospheric Ozone

23. Effect on World's Food Production

24. Thawing Permafrost & Tundra As Sources of CO2 Emissions

25. Disappearing Glaciers

26. Water Shortages & More Droughts

27. Increasing ocean storms and coastal erosion

28. Greenland - A key to accelerating climate change

29. The Sky is Rising

30. Disappearing Plankton - Bottom of the Food Chain

31. Threat to Krill - Food Source of Fish, Seabirds, Squids, Whales, Seals, Penguins

32. Threat to Winter Sports Industry

33. Carbon dioxide emissions increase acidity of ocean waters

Personal Solutions to Global Warming

Individual choices can have an impact on global climate change. Reducing your family's heat-trapping

emissions does not mean forgoing modern conveniences; it means making smart choices and using

energy-efficient products, which may require an additional investment up front, but often pay you back in

energy savings within a couple of years.

Since Americans' per capita emissions of heat-trapping gases is 5.6 tons—more than double the amount of

western Europeans—we can all make choices that will greatly reduce our families' global warming

impact.

1. The car you drive: the most important personal climate decision.

When you buy your next car, look for the one with the best fuel economy in its class. Each gallon

of gas you use is responsible for 25 pounds of heat-trapping gases in the atmosphere. Better gas

mileage not only reduces global warming, but will also save you thousands of dollars at the pump

over the life of the vehicle. Compare the fuel economy of the cars you're considering and look for

new technologies like hybrid engines.

2. Choose clean power. More than half the electricity in the United States comes from polluting

coal-fired power plants. And power plants are the single largest source of heat-trapping gas. None

of us can live without electricity, but in some states, you can switch to electricity companies that

provide 50 to 100 percent renewable energy. (For more information go to Green-e.org.)

3. Look for Energy Star. When it comes time to replace appliances, look for the Energy Star label

on new appliances (refrigerators, freezers, furnaces, air conditioners, and water heaters use the

most energy). These items may cost a bit more initially, but the energy savings will



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pay back the extra investment within a couple of years. Household energy savings really can make

a difference: If each household in the United States replaced its existing appliances with the most

efficient models available, we would save $15 billion in energy costs and eliminate 175 million

tons of heat-trapping gases.

4. Unplug a freezer.

One of the quickest ways to reduce your global warming impact is to unplug the extra refrigerator

or freezer you rarely use (except when you need it for holidays and parties). This can reduce the

typical family's carbon dioxide emissions by nearly 10 percent.

5. Get a home energy audit.

Take advantage of the free home energy audits offered by many utilities. Simple measures, such as

installing a programmable thermostat to replace your old dial unit or sealing and insulating heating

and cooling ducts, can each reduce a typical family's carbon dioxide emissions by about 5 percent.

6. Light bulbs matter.

If every household in the United States replaced one regular light bulb with an energy-saving

model, we could reduce global warming pollution by more than 90 billion pounds over the life of

the bulbs; the same as taking 6.3 million cars off the road. So, replace your incandescent bulbs

with more efficient compact fluorescents, which now come in all shapes and sizes. You'll be doing

your share to cut back on heat-trapping pollution and you'll save money on your electric bills and

light bulbs.

7. Think before you drive.

If you own more than one vehicle, use the less fuel-efficient one only when you can fill it with

passengers. Driving a full minivan may be kinder to the environment than two midsize cars.

Whenever possible, join a carpool or take mass transit.

8. Buy good wood.

When buying wood products, check for labels that indicate the source of the timber. Supporting

forests that are managed in a sustainable fashion makes sense for biodiversity, and it may make

sense for the climate too. Forests that are well managed are more likely to store carbon effectively

because more trees are left standing and carbon-storing soils are less disturbed.

9. Plant a tree.

You can also make a difference in your own backyard. Get a group in your neighborhood together

and contact your local arborist or urban forester about planting trees on private property and public

land. In addition to storing carbon, trees planted in and around urban areas and residences can

provide much-needed shade in the summer, reducing energy bills and fossil fuel use.

10. Let policymakers know you are concerned about global warming.

Our elected officials and business leaders need to hear from concerned citizens. Sign up for the

Union of Concerned Scientists Action Network to ensure that policymakers get the timely,

accurate information they need to make informed decisions about global warming solutions.

Causes for ozone depletion:-

Chloroflouro carbons (CFC) commonly known as Freon’s. These chemically stable (non reactive), odorless, nonflammable, nontoxic and non corrosive compounds are cheap to make.



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They are used as coolants in air conditioners and refrigerators (replacing toxic sulfur dioxide and

ammonia), propellants in aerosol spray can, Cleaners for electronic parts, sterility for hospital instruments,

Fumigants of granaries and bubbles in plastic foam used for Insulation and packaging.

In 1974, Chemists Sherwood Rowland and Mario Molina at the University of California indicated

that CFCS were lowering the average concentration of ozone in the stratosphere.

CFCs remain the troposphere because they are insoluble in water and are chemically unreactive.

Over, 11-20 years, they rise into the stratosphere mostly through convection, random drift and the

turbulent mixing of air in the troposphere.

Once they reach the stratosphere, the CFC, molecules break down under the influence of high

energy UV radiation.

It releases highly reactive ozone (O3) into O2 and O in a cyclic chain of chemical reactions. This

causes ozone in various parts of the stratosphere to be destroyed faster than it is formed.

CFCl3 + UV___ CFCl2 + Cl

Cl + O3 ---- ClO + O2

ClO + O ----- Cl + O2

Finally each CFC can last in the stratosphere for 65 -385 years. Depending on its type – the most

widely used CFCs last 75-111 years. During that time, each chlorine atom released from these molecules

can convert unto 1,00,000 molecules of O3 to O2.

Ozone depletion in Stratosphere:

A layer of ozone in the lower stratosphere keeps about 95% of the sun’s harmful UV radiation from reaching the earth’s surface. Formation of Ozone:-

Ozone is a form of oxygen and it contains three atoms of oxygen (O3)

-In the stratosphere ozone is continuously being created by the absorption of

short wave UV radiations.

UV radiations less than 242nm decompose molecular oxygen into atomic (O)

by photolytic decomposition.

(O2+UVB ---- O+O)

The atomic oxygen rapidly reacts with molecular oxygen to form ozone.

(O2+O ---- O3)

Some free oxygen atoms combine with O3 to form two oxygen molecules.

O+ O3 -------- O2 + O2

When ozone absorbs UVB, it is converted to free oxygen and molecular oxygen.

O3 + UVB ------O + O2

The amount of ozone in the stratosphere is dynamic.

However, the presence of CFC and other chemicals may alter this equilibrium. Ozone Concentration in

stratosphere is about 10ppm. This is disturbed by reactive atoms of chlorine, bromine etc, which destroy

ozone, molecules. It results in thinning of ozone layer generally called ozone hole. The amount of

atmospheric ozone is measured by Dobson spectra Photoemission and is expressed in Dobson units (DU).




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One DU =0 .01 mm.

Other Chemicals deplete ozone:-

CFCs are not the only ozone depleting compounds. Other examples are halons. Methyl bromide (

fumigant ), hydrogen chloride ( emitted by US space shuttles) and cleaning solvents such as carbon tetra

chloride, methyl chloroform, n-propyl bromide and hexachloride butadiene.

Effects of ozone layer depletion

Human health

Worse sunburn

Skin Cancer

Cataracts

Pterygium

Photo allergy

Premature ageing

Suppressed immune system

Crops

Impaired growth

Impaired photosynthesis

Poor crop yield

Affects nitrogen fixing bacteria

Damage DNA

Impaired reproductive capacity

Animals

Affects reproduction

Cancer

Affects whole eco system

THE RESPONSE TO OZONE LAYER DEPLETION

Vienna Convention for the Protection of the Ozone Layer was entered into force in 1985 and agreement

was made to take appropriate measures to protect the ozone layer and to do research, monitoring and

exchange of information

The Montreal Protocol on Substances that Deplete the Ozone Layer was entered into force in 1989. It

controls on production, consumption and use of ozone depleting substances (ODS)

United Nations declared September 16 as International Ozone Day

ACID RAIN

Acid rain is rain or any other form of precipitation that is unusually acidic. It has harmful effects on

plants, aquatic animals, and infrastructure. Acid rain is mostly caused by human emissions of sulfur and

nitrogen compounds which react in the atmosphere to produce acids.

Definition

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cloudwater, dew) and dry (acidifying particles and gases) acidic components. A more accurate term is

“acid deposition”. Distilled water, which contains no carbon dioxide, has a neutral pH of 7. Liquids with a

pH less than 7 are acidic, and those with a pH greater than 7 are bases. “Clean” or unpolluted rain has a slightly acidic pH of about 5.2, because carbon dioxide and water in the air react together to form

carbonic acid, a weak acid (pH 5.6 in distilled water), but unpolluted rain also contains other chemicals.[1]

H2O (l) + CO2 (g) → H2CO3 (aq)

Carbonic acid then can ionize in water forming low concentrations of hydronium and carbonate ions:

2 H2O (l) + H2CO3 (aq) CO32− (aq) + 2 H3O

+ (aq)

Emissions of chemicals leading to acidification

The most important gas which leads to acidification is sulfur dioxide. Emissions of nitrogen oxides which

are oxidized to form nitric acid are of increasing importance due to stricter controls on emissions of sulfur

containing compounds. 70 Tg(S) per year in the form of SO2 comes from fossil fuel combustion and

industry, 2.8 Tg(S) from wildfires and 7-8 Tg(S) per year from volcanoes.[15]

Natural phenomena

The principal natural phenomena that contribute acid-producing gases to the atmosphere are emissions

from volcanoes and those from biological processes that occur on the land, in wetlands, and in the oceans.

The major biological source of sulfur containing compounds is dimethyl sulfide.

Human activity

The principal cause of acid rain is sulfur and nitrogen compounds from human sources, such as

electricity generation, factories, and motor vehicles. Coal power plants are one of the most polluting. The

gases can be carried hundreds of kilometres in the atmosphere before they are converted to acids and

deposited.

Chemical processes

Combustion of fuels creates sulfur dioxide and nitric oxides. They are converted into sulfuric acid and

nitric acid.



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Gas phase chemistry

In the gas phase sulfur dioxide is oxidized by reaction with the hydroxyl radical via an intermolecular

reaction.

SO2 + OH· → HOSO2·

which is followed by:

HOSO2· + O2 → HO2· + SO3

In the presence of water, sulfur trioxide (SO3) is converted rapidly to sulfuric acid:

SO3 (g) + H2O (l) → H2SO4 (l)

Nitrogen dioxide reacts with OH to form nitric acid:

NO2 + OH· → HNO3

Wet deposition

Wet deposition of acids occurs when any form of precipitation (rain, snow, etc.) removes acids from the

atmosphere and delivers it to the Earth's surface. This can result from the deposition of acids produced in

the raindrops (see aqueous phase chemistry above) or by the precipitation removing the acids either in

clouds or below clouds. Wet removal of both gases and aerosols are both of importance for wet

deposition.

Dry deposition

Acid deposition also occurs via dry deposition in the absence of precipitation. This can be responsible for

as much as 20 to 60% of total acid deposition. This occurs when particles and gases stick to the ground,

plants or other surfaces.

Adverse effects

Acid rain has been shown to have adverse impacts on forests, freshwaters and soils, killing insect and

aquatic life-forms as well as causing damage to buildings and having impacts on human health.

Surface waters and aquatic animals

Both the lower pH and higher aluminum concentrations in surface water that occur as a result of acid rain

can cause damage to fish and other aquatic animals. At pH lower than 5 most fish eggs will not hatch and

lower pH can kill adult fish. As lakes and rivers become more acidic biodiversity is reduced. Acid rain has

eliminated insect life and some fish species.

Soils

Soil biology and chemistry can be seriously damaged by acid rain. Some microbes are unable to tolerate

changes to low pH and are killed. The enzymes of these microbes are denatured (changed in shape so they

no longer function) by the acid. The hydronium ions of acid rain also mobilize toxins such as aluminium,

and leach away essential nutrients and minerals such as magnesium.Soil chemistry can be dramatically

changed when base cations, such as calcium and magnesium, are leached by acid rain thereby affecting

sensitive species, such as sugar maple (Acer saccharum).

Forests and other vegetation

Adverse effects may be indirectly related to acid rain, like the acid's effects on soil (see above) or high

concentration of gaseous precursors to acid rain. High altitude forests are especially vulnerable as they are

often surrounded by clouds and fog which are more acidic than rain.



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Other plants can also be damaged by acid rain, but the effect on food crops is minimized by the

application of lime and fertilizers to replace lost nutrients.

Human health

Scientists have suggested direct links to human health. Fine particles, a large fraction of which are formed

from the same gases as acid rain (sulfur dioxide and nitrogen dioxide), have been shown to cause illness

and premature deaths such as cancer and other diseases.

Other adverse effects

Acid rain can also cause damage to certain building materials and historical monuments. This results

when the sulfuric acid in the rain chemically reacts with the calcium compounds in the stones (limestone,

sandstone, marble and granite) to create gypsum, which then flakes off.

This result is also commonly seen on old gravestones where the acid rain can cause the inscription to

become completely illegible. Acid rain also causes an increased rate of oxidation for iron. Visibility is

also reduced by sulfate and nitrate aerosols and particles in the atmosphere.

Prevention methods

1. Improvement in technologies and switching to clean combustion technologies are highly

essential in order to monitor the air pollution.

2. Emissions of SO2 and NO2 from industries and power plants should be reduced by using

pollution control equipments.

3. Coal with lower sulphur content is desirable to use in thermal plants. Replacement of coal

by natural gas would also reduce the problem.

4. Liming of lakes and soils should be done to correct the adverse effect of acid rain.

5. The real solution is to cut back on the use of fossil fuels by reducing our dependency on

motor vehicles and unnecessary utility of motor articles.

Environmental laws

In the Constitution of India it is clearly stated that it is the duty of the state to ‘protect and improve the environment and to safeguard the forests and wildlife of the country’. It imposes a duty on every citizen ‘to protect and improve the natural environment including forests, lakes, rivers, and wildlife’. Reference to the environment has also been made in the Directive Principles of State Policy as well as the

Fundamental Rights. The Department of Environment was established in India in 1980 to ensure a healthy

environment for the country. This later became the Ministry of Environment and Forests in 1985.

The constitutional provisions are backed by a number of laws – acts, rules, and notifications. The EPA

(Environment Protection Act), 1986 came into force soon after the Bhopal Gas Tragedy and is considered

an umbrella legislation as it fills many gaps in the existing laws. Thereafter a large number of laws came

into existence as the problems began arising, for example, Handling and Management of Hazardous

Waste Rules in 1989.

Following is a list of the environmental legislations that have come into effect:

General, Forest and wildlife, Water, Air

General

1986 - The Environment (Protection) Act authorizes the central government to protect and improve



http://en.wikipedia.org/wiki/Particulate


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environmental quality, control and reduce pollution from all sources, and prohibit or restrict the setting

and /or operation of any industrial facility on environmental grounds.

1986 - The Environment (Protection) Rules lay down procedures for setting standards of emission or

discharge of environmental pollutants.

1989 - The objective of Hazardous Waste (Management and Handling) Rules is to control the

generation, collection, treatment, import, storage, and handling of hazardous waste.

1989 - The Manufacture, Storage, and Import of Hazardous Rules define the terms used in this

context, and sets up an authority to inspect, once a year, the industrial activity connected with hazardous

chemicals and isolated storage facilities.

1989 - The Manufacture, Use, Import, Export, and Storage of hazardous Micro-organisms/

Genetically Engineered Organisms or Cells Rules were introduced with a view to protect the

environment, nature, and health, in connection with the application of gene technology and

microorganisms.

1991 - The Public Liability Insurance Act and Rules and Amendment, 1992 was drawn up to provide

for public liability insurance for the purpose of providing immediate relief to the persons affected by

accident while handling any hazardous substance.

1995 - The National Environmental Tribunal Act has been created to award compensation for damages

to persons, property, and the environment arising from any activity involving hazardous substances.

1997 - The National Environment Appellate Authority Act has been created to hear appeals with

respect to restrictions of areas in which classes of industries etc. are carried out or prescribed subject to

certain safeguards under the EPA.

1998 - The Biomedical waste (Management and Handling) Rules is a legal binding on the health care

institutions to streamline the process of proper handling of hospital waste such as segregation, disposal,

collection, and treatment.

1999 - The Environment (Siting for Industrial Projects) Rules, 1999 lay down detailed provisions

relating to areas to be avoided for siting of industries, precautionary measures to be taken for site selecting

as also the aspects of environmental protection which should have been incorporated during the

implementation of the industrial development projects.

2000 - The Municipal Solid Wastes (Management and Handling) Rules, 2000 apply to every

municipal authority responsible for the collection, segregation, storage, transportation, processing, and

disposal of municipal solid wastes.

2000 - The Ozone Depleting Substances (Regulation and Control) Rules have been laid down for the

regulation of production and consumption of ozone depleting substances.

2001 - The Batteries (Management and Handling) Rules, 2001 rules shall apply to every manufacturer,

importer, re-conditioner, assembler, dealer, auctioneer, consumer, and bulk consumer involved in the

manufacture, processing, sale, purchase, and use of batteries or components so as to regulate and ensure

the environmentally safe disposal of used batteries.

2002 - The Noise Pollution (Regulation and Control) (Amendment) Rules lay down

such terms and conditions as are necessary to reduce noise pollution, permit use of loud speakers or public




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address systems during night hours (between 10:00 p.m. to 12:00 midnight) on or during any cultural or

religious festive occasion

2002 - The Biological Diversity Act is an act to provide for the conservation of biological diversity,

sustainable use of its components, and fair and equitable sharing of the benefits arising out of the use of

biological resources and knowledge associated with it

Forest and wildlife

1927 - The Indian Forest Act and Amendment, 1984, is one of the many surviving colonial statutes. It

was enacted to ‘consolidate the law related to forest, the transit of forest produce, and the duty leviable on timber and other forest produce’. 1972 - The Wildlife Protection Act, Rules 1973 and Amendment 1991 provides for the protection of

birds and animals and for all matters that are connected to it whether it be their habitat or the waterhole or

the forests that sustain them.

1980 - The Forest (Conservation) Act and Rules, 1981, provides for the protection of and the

conservation of the forests.

Water

1882 - The Easement Act allows private rights to use a resource that is, groundwater, by viewing it as an

attachment to the land. It also states that all surface water belongs to the state and is a state property.

1897 - The Indian Fisheries Act establishes two sets of penal offences whereby the government can sue

any person who uses dynamite or other explosive substance in any way (whether coastal or inland) with

intent to catch or destroy any fish or poisonous fish in order to kill.

1956 - The River Boards Act enables the states to enroll the central government in setting up an

Advisory River Board to resolve issues in inter-state cooperation.

1970 - The Merchant Shipping Act aims to deal with waste arising from ships along the coastal areas

within a specified radius.

1974 - The Water (Prevention and Control of Pollution) Act establishes an institutional structure for

preventing and abating water pollution. It establishes standards for water quality and effluent. Polluting

industries must seek permission to discharge waste into effluent bodies.

The CPCB (Central Pollution Control Board) was constituted under this act.

1977 - The Water (Prevention and Control of Pollution) Cess Act provides for the levy and collection

of cess or fees on water consuming industries and local authorities.

1978 - The Water (Prevention and Control of Pollution) Cess Rules contains the standard definitions

and indicate the kind of and location of meters that every consumer of water is required to affix.

1991 - The Coastal Regulation Zone Notification puts regulations on various activities, including

construction, are regulated. It gives some protection to the backwaters and estuaries.

Air

1948 – The Factories Act and Amendment in 1987 was the first to express concern for the working

environment of the workers. The amendment of 1987 has sharpened its environmental focus and

expanded its application to hazardous processes.

1981 - The Air (Prevention and Control of Pollution) Act provides for the control and abatement of air




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pollution. It entrusts the power of enforcing this act to the CPCB .

1982 - The Air (Prevention and Control of Pollution) Rules defines the procedures of the meetings of

the Boards and the powers entrusted to them.

1982 - The Atomic Energy Act deals with the radioactive waste.

1987 - The Air (Prevention and Control of Pollution) Amendment Act empowers the central and state

pollution control boards to meet with grave emergencies of air pollution.

1988 - The Motor Vehicles Act states that all hazardous waste is to be properly packaged, labelled, and

transported.

ENVIRONMENTAL PROTECTION ACT, 1986

The Bhopal gas mass disaster on 3rd December 1984 led the government to enact EPA. According

to this act the definitions of “environment”, “environmental pollution” and “hazardous substances” are given below.

Environment: It includes water, air and land and the inter relationship which exists among and between

water, air and land and human beings, other living creatures, plants, microorganisms and property.

Environmental pollution: It means any solid, liquid or gaseous substances present in such concentration

as may be or tend to be injurious to environment.

Hazardous substances: Any substance which by reason of its chemical or physiochemical properties is

liable to cause harm to human being, other living creatures, plants, microorganisms, property or the

environment.

This act is a broad based environmental legislation. Under this act, central government is

authorized to develop new national standard for the quality of the environment; to regulate cities of big

industries; to prescribe procedure for manufacturing hazardous chemicals; for preventing accidents and

to collect and disseminate information regarding environmental pollution

OBJECTIVES

1. Plans and executes a nationwide programme for the prevention, control and abatement of

environmental pollution.

2. Provision to tackle various types of pollution, such as water pollution, air pollution, noise

pollution etc.

3. Lays down standards for emission or discharge of environmental pollutions from various

sources whatsoever.

4. An individual person can also approach court against the polluter.

PENALTIES:

1. Imprisonment for a term which may extend to five years or fine, which may extend to one

lakh rupees or both.

SUGGESTIONS

1. Having a knowledge of standards for various pollution,

2. Adhering to the laws strictly,

3. Representing any public causes in the court,

4. Participating in the awareness activities, and

5. Celebrating eco-concern days.




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AIR (PREVENTION AND CONTROL OF POLLUTION) ACT, 1981

To obligate the U.N conference on the human environment held at Stockholm in June 1972, our

parliament enacted the air (Prevention and control of pollution) Act in 1981.The main objective of

enacting this law is to control air pollutant sources so that ambient pollutant concentration are reduced to

levels considered safe. The framework of this act is similar in the line of water act.

OBJECTIVES

1. It deals only with air pollution.

2. This act leads to establishment of state and central to control measures.

3. It empowers the state government to declare air pollution areas and to prohibit the use of

any fuel which is likely to cause air pollution.

4. This act helps to maintain performance standards of anti- pollution control measures.

5. The state boards are required to prescribe emission standard for industry and automobiles

in consultation with central boards.

6. Under this act, all industries operating within designated areas shall have to obtain a permit

from the respective state boards.

The act was amended in 1987 to strengthen the enforcement machinery and prescribing

stiffer penalties. Under this amendment act the state boards may close down a defaulting industrial plant

or may stops its supply of electricity or water or may move to the court.

The other acts relating to air pollution are,

1. The factories Act,1948.

2. The Industries ( Development and regulation) Act, 1951

3. The Indian Explosives Act, 1884

4. The explosive substances Act,1908

PENALTIES

Each violation may be punished with imprisonment for six months to one year which may

extend upto six years, with additional fine of five thousand rupees.

SUGGESTIONS

1. Reducing the usage of fuels for example instead of using motor cycles to travel a short

distance, we can walk or can use bicycles.

2. We can reduce the usage of green house gases, which creates hole in the ozone layer.

3. We can file complaints against the violating industries, in a court of law.

WATER (PREVENTION AND CONTROL OF POLLUTION) ACT 1974

In 1974 Indian parliament came out for the first time legislation for controlling water pollution by

enacting Water (prevention and Control of pollution) Act. It was passed with the object of prevention and

control of water pollution and restoring the wholesomeness of the water quality.

OBJECTIVES

1. This act makes provision for constituting the central and state pollution control boards.

2. The central board should advice central government on matters pertaining to prevention and




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control of water pollution.

3. It restricts the usage of wells, ponds or lakes to discharge the waste water.

4. The board has power to take appropriate remedial action when an accident occur causing

pollution.

5. The board has the power to enter and inspect any plant, record, register, document etc and give

directions.

The Board’s function includes advice to control government concerning the prevention and control of water pollution and coordinating the efforts of state boards, giving technical assistance and guidance to

states. Sponsoring of research and training of person engaged in the field of water pollution. The act was

amended in 1988 to strengthen the acts implementation provisions.

PENALTIES

1. Imprisonment for a period of three months or fine upto Rs.5000 or both.

2. In cases of continuing violations, an additional fine extending to Rs.1000 per day of violations.

SUGGESTIONS

1. Avoiding wastage of water

2. Preventing water pollution

3. Recycling the wastewater

WILDLIFE (PROTECTION) ACT,1972

India is probably the first country to enact a wildlife protection act. The wild birds and

animals protection act was first enacted in 1887 and in 1912. A new Wildlife (protection) Act was again

enacted in 1972. Under this act, possession, trapping, shooting of wild animals, serving their meat for

eating, their transport and export(alive or dead) are all controlled and watched by chief wildlife warden

and other authorized officers under him.

OBJECTIVES

1. Mainly aims at the protection of wild animals and plants.

2. Hunting of wild animals is strictly prohibited especially female and young ones.

3. Threatened species are completely protected and others have been provided protection according

to their state of population size etc.

4. Under this act provisions are given to establish sanctuaries, national parks and biosphere reserves.

5. It empowers individuals to file complaints against offends.

6. The acts and laws enforced for wildlife protection should be given to those who are found guilty.

The other Acts related to wild life conservation are.

1. The Madras elephant preservation Acts (1873 and 1879)

2. The Indian Arms Acts (1978)

3. The wild birds and animals Protection Act 1932.

PENALTIES

Violators of this law are punishable with simple imprisonment for a term, which may extend to

3 years or with fine which may extend toRs.25,000/- or with both.

SUGGESTIONS




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1. Hunting of animals should be stopped

2. Killing of animals for profit though sale of their fur & products and buying them should be

avoided.

3. Birds and animals should be protected; we should love them and care for them.

4. We should visit the sanctuaries, national parks and biosphere reserves to see the natural life

style of animals.

FOREST (CONSERVATION) ACT, 1980

Today we have only 74mha of officially notified forests land. The area covered by good natural

forests is substantially lesser than that. Thus with a view to conserve forests and to stop the

growing deforestation and the resulting environment degradation the parliament enacted this act.

OBJECTIVIES

I. To protect the forests from illegal cutting, encroachment, fire, grazing and shifting

cultivation.

II. To develop a network for future planning

III. To improve forest productivity

IV. It mainly aims at preventing deforestation activity

V. The reserved forest should not dereserved without prior permission of central government

VI. A committee is constituted under the act to look into above said proposals.

Six regional offices have been established at Bangalore, Bhopal, Bhubaneshwar, Lucknow,

Shillong and Chandigarh to monitor the implementation of the conditions imposed while

conveying approval for diversion of forest land non-forest use and also to evaluate on going forest

development projects and schemes.

PENALTIES

Whoever contravenes or abates the contravention of any of the provisions in this law shall

be punishable with simple imprisonment for a period which may extend to 15 days.

SUGGESTIONS

1. Cutting of trees should be avoided

2. we should practice the habit of planting trees

3. creating awareness among people

4. Minimizing the use forest products must be practiced (Eg. Paper, wood etc.)

ISSUES INVOLVED IN THE ENFORCEMENT OF ENVIRONMENTAL LEGISLATION

At present Indian environmental law is in era of new developments. The Environment

protection bill was passed to rectify some loopholes that were noticeable in earlier laws.

Environmental law is an open system of various legal tools and instruments to combat pollution.

These instrument vary greatly and may be used alternatively or cumulatively such as,

administrative measures accompanied by penal and civil actions. The other problems which are

involved in the enforcement of environmental legislation are as follows:

1. Lack of awareness among the people,

2. Lack of cooperation between the people and the various responsible agencies,

3. Lack of direction in line of attack,




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4. Lack of inter-linkages among the various agencies,

5. Lack of proper infra structure,

6. Lack of funds,

7. Lack of truthfulness on the part of industries,

8. Lack of sufficient manpower in pollution control boards,

9. Lack of information storage,

10. Lack of surveillance to identify willful defaulters,

11. Lack of innovative approach in the study and

12. Frequent change of the chairman and the member secretary.

THE NEED FOR PUBLIC AWARENESS

Man started playing a very important part in shaping his environment, and he has been

responsible for degrading the quality of his environment ever since he appeared on this earth. At

first he contaminated the atmosphere by the use of fire, which added gases, smoke and ash to it.

When he came out of the cave age and began to settle into village, towns and cities, the situation

gradually worsened. The degradation of the environment was caused mostly by his activities such

as burning of wood, smelting of ores, tanning leather, primitive methods of sewage disposal and

so on. With the advent of industrial revolution, coupled with urbanization, all kinds of impurities

began to be added to the natural air, water, as well as soil, causing almost irreparable damage to

environment. Some of the problem such as depletion or resource, soil erosion, pollution,

deforestation and extinction of wild animals due to increased human population has reached global

level.

Legal and regulatory framework

Basis for action

Laws and regulations suited to country’s specific conditions are among the most important instruments for transforming into a better and friendly environment and development policies into

action, not only through “command and control” methods, but also a formative framework for economic planning and market instruments. Yet, although the volume of legal texts in this field is

steadily increasing, much of the law making in many countries seems to adhoc and piecemeal, or

has not been endowed with the necessary institutional machinery and authority for enforce and

timely adjustment.

While there is continuous need for law improvement in the countries, many developing

countries have been affected by shortcomings of law and regulations. To effectively integrate

environment and development in the policies and practices of each country, it is essential to

develop and implement integrated, enforceable and effective laws and regulations that are based

upon social, ecological, economic and scientific principles. It is equally critical to develop

workable programmes to review and enforce compliance with the laws, regulations and standards

that are adopted. Technical support may be needed for many countries to accomplish these goals.

Technical cooperation requirements in this field include legal information, advisory services and

specialized training and institutional capacity building.

The enactment and enforcement of laws and regulations (at the regional, national,




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state/provincial or local/municipal level) are also essential for the implementation of most

international agreements in the field of environment and development, as illustrated by the

frequent treaty obligation to report on legislative measures. The survey of existing agreements

undertaken in the context of conference preparations has indicated problems of compliance in this

respect, and the need for improved national implementation. In developing their national priorities,

countries should take account of their international obligations.

Objectives

The overall objective is to promote, in the light of country-specific conditions, the

integration of environment and development policies through appropriate legal and regulatory

policies, instruments and enforcement mechanisms at the national, state, provincial and local level.

Recognizing that countries will develop their own priorities in accordance with their needs and

national and, where appropriate, regional plans, policies and programme.

Making laws and regulations more effective

Governments, with the support, where appropriate, of competent international organizations,

should regularly assess the laws and regulations enacted and the related

institutional/administrative machinery established at the national/ state and local/municipal level

in the field of environment and sustainable development, with a view to rendering them effective

in practice.

Programmes for this purpose could include the promotion of public awareness, preparation

and distribution of guidance material, and specialized training, including workshops, seminars,

education programmes and conferences, for public officials who design, implement, monitor and

enforce laws and regulations.

Public awareness

At this juncture, it is unavoidable and essential to have knowledge about the environment

in which we are living, its status, and our position and role in the environment degradation, and

our responsibility to reconstruct and establish a harmonious living pattern with other forms of life.

Knowing, understanding, and applying the technology in accordance with the rules and

regulations of environmental ethics is vital to the sustainable development, and prosperity of

humanity.

Awareness Generation

The awareness on the above lines could be generated through the following

agencies/programmes:

1. Governmental agencies, 2. Environment Campaign, 3. Non-Governmental agencies, 4.

Educational Institutions, 5. Youth clubs, 6. Environment Activists, 7. Mass media, 8. Visual

Communication, 9. Building local partnerships, 10. Eco-Development camps, 11. National Public

Awareness campaign, 12.ENVIS Nodes, 13. Environmental Awareness Education, 14.

Information Technology, 15.Observing/Celebrating various eco-concern days.




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UNIT –V

HUMAN POPULATION AND THE ENVIRONMENT

The term population, as defined by Clarke in 1954, refers to the total number of individuals of the same

species occupying a particular geographical area at a given time.

Human population is increasing at a great rate all over the world, and India, unfortunately, is leading the

charge. A rise in population directly affects the environment and development. In the beginning of human

civilization, during the stone age, the population was quite stable. The 14th century experienced large

scale deaths due to plague when about 50% people in Asia and Europe died due to diseases. With

scientific and technological advancement, life expectancy increased. People started living in definite

settlements which lead to a stable life. Scientists conquered infant mortality and famine-related deaths.

Population growth climbed to unprecedented heights, at the rate of 3-4% a year, accounting for about 90-

95% of the total population growth of the world in the last 50 years

The population of the world, which was 2.5 billion in 1950, had increase to 6.6 billion by 2006. It is

expected to increase to about 8 billion by 2020. The rapid growth in population has caused a global

environment crisis. A larger population means a requirement of greater Natural resources. To this end,

people are gradually converting natural ecosystems of the world to man-managed ecosystem.

EFFECT OF POPULATION GROWTH

Increase in population has lead to several socio-economic problems. Some of them are described below:

1. More deforestation activities arising to meet the requirements of fuel wood,

agriculture, settlement, and also for industrial establishments.

2. Excessive exploitation of natural resources causes ecological imbalance in nature. An

increase in the number of people means that a majority of them end up living in

poverty and have decreased access to social, health, and education services.




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Unemployment is another serious problem arising because of overpopulation.

3. The indiscriminate felling of trees for agricultural expansion and timber products has

lead to the degradation of watersheds, thereby affecting the water catchments areas.

4. Due to the increasing population pressure, water resources are exploited more and

more for various uses including domestic, livestock, and industrial uses further, it has

lead to the extensive economic activities and rising pollution in rivers, lakes, and

ponds. Water crisis also lead to water allocation and user conflicts.

5. Population growth affects the availability of nature resources. It causes increase in

demand for food, water, arable land other essential materials, such as firewood.

VARIATION OF POPULATION AMONG NATIONS

WORLD POPULATION DISTRIBUTION

Population growth rates vary greatly among countries and also between regions of the same

countries. It is so because climatic conditions and reproductive potential of various countries vary. For

example, the population of china in 2002 was 1285 million and that of Naru (located in south pacific) in

2002 was 11,845 only. Asia accounts for over 60% of the world population with almost 3.8 billion people.

China and India alone comprise 20% and 16% respectively. Africa follows with 840 million people, 12%

of the world population. Europe’s 710 million people make up 11% of the world’s population. North America is home to 514 million (8%), and South America to 371 million (5.3%).

Australia, Canada, New Zealand, and the United States have the highest population growth rates,

which may be due to the effect of immigration. Hungary, Italy, Latvia, Portugal, the Russian Federation,

and Spain are countries which have population growth near zero, a number of eastern European countries

are reflecting negative population growth due to poorer health and rising death rates, as well as

emigration. The population of south central Asia, which includes the Indian sub-continent, Iran , and five

former soviet republics, is likely to increase by about 50 percent over the next 30 years, while Pakistan’s fertility rates remain persistently high, family size in Bangladesh in now declining steadily. India presents

a mixed picture, with high rates of fertility in the north of the country and low ones in the south.

Throughout the region, efforts to improve the states of women, including better reproductive health care

and education, are gaining momentum.

FACTORS AFFECTING VARIATION OF POPULATION

Following are the factors affecting the variation of population among nations:

1. Age of human settlement:

Australia and the USA have low density of population. Human habitation in these countries is of

recent origin. Besides this, these countries also practice strict immigration procedures which manage to

keep the population density far below the total potential.




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2. Means of transport and communication

Highly developed means of air, surface, and water transport and communication add to the density of

population in a particular region because people can carry on agricultural, commercial, and industrial

activities very safely and swiftly.

3. Cultural factors

The density of population is low in areas where nomadic tribes live who are engaged in food gathering

to support their families.

4. Soils

East and south East Asian region, and the northern plains of India are densely populated because these

lands are fertile and produce a variety of crops to support dense populations.

5. Climatic conditions

Moderate climate leads to the growth of population because it is pleasant and refreshing. In these

regions, density of population is high. Similarly, Canada is sparsely populated because of the cold climate

prevailing there. In India, Rajasthan, Deccan hills and the Himalayan regions are sparsely populated.

6. Natural resources

Areas having rich wealth of natural resources like coal, water, minerals, and forest wealth favour the

growth of population, because these resources help in the development of trade and industry.

POPULATION CONTROL

High population growth adversely affects growth economy through its harmful

effects on production, natural resources, labour supply, and capital formation. There is an increase of

three humans per second in human population because in every second, five children are born and two

other people die. The difference between birth rate and death rate is three. This boom in population

growth is known as ‘population explosion. Population control is the practice of limiting population increase, usually by reducing birth rate.

A. TEMPORARY METHODS

These methods are used for the temporary avoidance of pregnancy. These include:

1. MECHANICAL METHODS

THE DIAPHRAGM

The diaphragm works by keeping the sperm from entering the cervix and going

into the uterus.

INTRAUTERINE DEVICES

An intrauterine device (IUD) usually is a small, flexible plastic frame. It often

has a copper wire or copper sleeves on it. It is inserted into a women’s uterus through her vagina. CONDOM

A condom is a device, usually made of latex, or polyurethane, that is used during

sexual intercourse.

2. CHEMICAL METHODS

SPERMICIDES are chemicals that make the sperm unable to function, or, we can say,

they ‘kill’ sperm.




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ORAL CONTRACEPTIVES are medically prescribed drugs that inhibit normal fertility.

3. NATURAL METHODS

The rhythm method is a method of natural birth control that involves counting the days of

a women’s menstrual cycle in order to achieve or avoid pregnancy. STERILIZATION

These methods of contraception are permanent in their effect on the ability to conceive.

These include:

Vasectomy provides permanent contraception for men who have decided that they

do not want more children.

Female sterilization provides permanent contraception for women who do not want

more children.

ABORTION

In India, abortion is not a family planning measure . In 1971, a law called the ‘Medical Termination of pregnancy act’ was passed permitting legal abortion on grounds, of health of the mother, humanitarian grounds, or in case of risk of physical and mental abnormalities to the child.

FAMILY WELFARE PROGRAMMES

A family planning programme is a programme that works on checking the problem of

population explosion. Unfortunately, the family welfare programme is widely misunderstood in India as

a family planning programme. Most experts believe that it is a powerful tool to check the population

growth for lesser developed countries. Family welfare programme can accelerate the decline in birth rate.

The Family Welfare programme in India has been initiated by the Heath Department of the Indian

Government. A combination of good access to family planning services and high levels of education

among women has supported declining fertility rates in southern India and Sri Lanka. Family planning is

directly related to the health and welfare of women and prosperity of nation in general terms. The success

of the programme depends upon public awareness, education of women, proper family counseling, and

easy availability of means of birth control. Better medical facilities and nutritional programmes also

support such family welfare programmes.

Family Welfare Programmes

Measures for population control

India chalked out and adopted the policy of family planning. Upto fifth Five year plan

Government allotted good sum of money but it was not satisfactory.

In 1976 the Government announced revised population policy, marriage age for boys 21 and for

the girls it was fixed 17.

The census of 1971 was considered as the base for allocating central grants to the plans of

different states in the sphere of family planning. Population control and related family welfare

programmes.

Special stress and necessary efforts were made for the education of women, particularly in the

rural and backward areas to imbue the knowledge of family planning.

Basic infrastructure related programmes

a. Family Welfare services are provided to the community through a network of Subcentres,




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Primary Health Centres(PHCs) and Community Health Centres(CHCs) in the rural areas and hospitals

and dispensaries etc. in the urban areas. This network, being set up under the minimum needs

programme (now reorganized as Basic Minimum Services (BMS) programme), is also supported by

an expanding number of Post Partum Centres at district and sub-district levels.

b. The Child Survival and safe Motherhood (CSSM) programme

c. Reproductive child Health (RCH) programme

d. Child Health Programme

e. Universal Immunization Programme

ENVIRONMENT AND HUMAN HEALTH

Definitions of Environment Health

Agency for Toxic Substances and Disease Registry-“Environment health is the branch of public health that protects against the effects of environmental hazards that can adversely effect health

or the ecological balances essential to human health and environmental quality”. The Archives of Environmental Health publishes articles dealing with the effects of

environmental agents on human health. These include epidemiological, clinical, or experimental

studies of man. “Environment” involves occupational or personal environments as well as the global

environment, land, water, and air.

Types of Pollution and Health Problems-Air Pollution and Health

Atmospheric pollution is on a global scale. However, it is not only that air over our cities that is

polluted, the entire atmosphere of our planet is now affected to some degree. Automobiles and

industries are responsible for the largest part of this form of pollution, which in some cities is so bad

as to have resulted in number of diseases. Air pollution had also resulted in heart diseases, increased

blood pressure, cancer, and bronchitis amongst other diseases. Long periods of heavy air pollution in

cities have increased the illness and death rate significantly. Most materials get soiled and wear out

faster in pollutes air. Metals like silver and brass get tarnished quickly on long exposure to polluted

air.

Housing Shelter and Health

Shelter is one of the essential requirements for human life. Uncontrolled migration from rural to

urban areas makes housing a major problem. Poor housing has been shown to be associated with

tuberculosis, streptococcal infection, rheumatic fever and rheumatic heart diseases. Housing must be

so designed and constructed as to allow adequate air and sunlight to enter and at the same time,

protect its dwellers from the elements. Where firewood, coal or cow dung cakes are used for cooking,

housing must be provided with smokeless ‘chulhas’ and proper ventilation to let out the smoke from the burning fire, thereby keeping the indoor clean. Residents should have access to safe drinking

water, waste disposal sites and sanitary latrines.

Water and Health

Water pollution reduces the amount of pure, clear, fresh water that is available for drinking

and personal use and for such activities like fishing, swimming and water sports.




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Like air, water pollution is also directly related to population growth, modernization and

insensitivity to the hazards of pollution. Day by day, larger volumes of wastes from industries and

homes are dumped into water bodies. Cycle, which was earlier maintained by the forces of nature,

cannot deal with the new harmful products produced by industries, which are non-biodegradable. In

fact, these products are a threat to marine life and to humans. Humankind is directly affected if such

water is used for drinking or personal use. Food from contaminated waters or food grown using such

water is consumed, toxins and pathogens are transferred to humans.

Solid Waste and Health

Solid wastes are the most visible pollutants which litter roadsides and surroundings and

are seen floating in rivers and streams. Unsightly dumps are seen around heavily populated urban

areas. Solid wastes include rubble from demolished buildings, garbage and litter like used cars, broken

bottles, polythene bags, metal scraps, tyres and tubes, rags, rusty equipment, broken furniture, old

automobiles etc. Garbage pollution makes the local conditions unhygienic which affects the lives of

residents of surrounding areas. To solve the problem of solid waste should ideally be sorted at the

source, collected in separate bags and sent for recycling or composting. This will help in saving

valuable resources. In India rag pickers collect recyclable waste from garbage dumps for their

livelihood. This will drastically reduce the volume of garbage to be disposed off daily and indirectly

reduce pollution.

Radiation and Health

Radioactive pollution or Nuclear Radiation is a potential health hazard of modern times.

Radioactive substances emit extremely dangerous invisible radiation, which can bring about biological

and chemical changes in body cells. Nuclear radiation comes from testing of nuclear weapons and

from nuclear power plants. Ionizing radiation causes mutations, abnormality and lethality in many

organisms, including man. Cancer is commonly caused even under low-level exposures. Radiation

effects persist for a very long period in the environment. Therefore, an utmost caution and complete

foolproof of technology is needed in handling such scientific activities to prevent radioactive

pollution. Lasers, microwave ovens, computer, televisions set and X-ray machines produce

electromagnetic radiation effect on human health in small doses.

Noise Pollution

Sound is produced in many kinds of work and we use and enjoy sound in talk and music. Only

when sound is not liked or unwanted we call it as noise. With rapid urbanization and technological

development, people living in or near cities are often exposed to loud noises. The loud screeching,

gritting or vibrating noise is created by various machines and means of transport. Blaring music,

announcements, television broadcast and fire crackers can affect work and sleep.

Noise can also cause psychological disorders due to a constant strain on the nervous system. It

may also be responsible for development for ulcers and high blood pressure and sometimes it

damages eyesight, brain and liver functioning. While fighting noise pollution it should be remembered

that silence is not only golden but healthy also.

Environmental Protection

Environment protection includes within its compass a wide range of activities such as prevention




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and control of water and air pollution, the maintenance of ecological balance and conservation of non-

renewable resources and proper and careful use of renewable resources. A major issue confronting is

ecology. The term ecology is taken from since, where it means the interrelation of organism and its

environment. In the present century, scientists and technologies have been made greater technological

advances, but the break-through create ecological imbalances. The uncontrolled cutting of trees has

led to extensive impairment of potential cultivable areas and compounded the problems of draught and

nutrition. Of course the most important issue confronting the industrial house and prevention and

control for air, water, noise and solid waste pollution and protecting the society from the leakage of

toxic gasses, explosion and fires resulting out of industrial activity.

Sustainable Approach and Health

Environment deterioration is the main factor in aggravating poverty and disease. Investment in

providing clean, fresh drinking water and sanitation-better drainage, latrines and clean streets and

roads is sustainable approach to environment, human and health and human resource development.

Costs of such an environmental and preventive approach are much smaller, wider in reach than the

mere curative approach of modern medicine. Improvement in environment and health conditions

should be attempted through people’s education, which is participatory in nature. Poverty alleviation programmes and improvement in food and nutrition have to be undertaken. In brief holistic approach

to disease and health taking into account the economic, socio-cultural and environmental factors has

to be adopted in India. The United Nations Conference on Environment and Development the Rio

Declaration, the Agenda 21, the convention on biodiversity and the statement on Forest principles

states: “Indigenous people and their communities and other local communities have a vital role in environmental management and development because of their knowledge and traditional practices…” Regarding the importance of indigenous or traditional medicine, Bodekar notes that an integrated

approach involving traditional and modern health system of medicine is environment friendly and the

case of new strains of malaria resistance virus indicates that the herbal medicine such as cinchona bark

is more effective because of its synergistic or all round effectiveness. In WHO’s word, “a ‘holistic’ view of environment and human health is gaining recognition”. Thus, traditional as well as modern health practices must adopt such a sustainable approach to environment as well as human health.

Suggestions

Convert polluting wastes into harmless products, which are environmentally acceptable.

Recycle the wastes in the same process

Use the waste as the resource or raw material for another process

The raw material used for combustion should be changed. For example, triethyl lead has been

replaced in gasoline as lead was the major pollutant in automobile exhausts.

Equipment should be designed to trap particulates and prevent their release into the

atmosphere, for example, through use of filters in equipment.

Effluent from factories should be treated before it is released

Control on the use of pesticides, fertilizers and radioactive materials should be practiced.

While planning cities and industrial areas, the environment should be preserved, trees should be

planted, parks and gardens should be included in the plan and congestion should be avoided.




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Awareness should be created among citizens about environment related health problems arising

because of rapid and unplanned development and population growth. Collective action on their part

can greatly help in prevention and control of pollution.

HUMAN RIGHTS

UNDERSTANDING HUMAN RIGHTS

Human beings have every right to lead a happy and healthy life. Alone with evolution,

relationships of human within nature and society have also changed. They raised their voice against

religions compulsions, socioeconomic restraints and sometimes against scientific discoveries, right from

the 13th century. How ever, the concept of human right came into existence after the United Nations

universal declaration of human right (UNDHR) in December 1948. UNDHR empowers man with right to

life, freedom, security, law, freedom of thought and expression, equal pay for work, education health care

and rest.

Once out of every five persons does not have enough energy to cook and one out of every five

persons is very poor. Such people hardly think in terms of education, prevention of child labour, or

anything but a loaf of bread for their families.

Economic and social disparity occurs amongst developed, developing, and poor countries. World

conference on human right held at Vienna in 1993, stressed upon the equal economic and social rights.

The concept of human right in India mainly focuses upon bonded labour, child and women abuse,

torture of poor people, custodial deaths, and violence in society. Although the Indian constitution equips

every citizen of India with civil, political, economic, and social right, yet violation of right occurs in India

quite frequently.

The significance of Human Right

Human rights are universal in nature. A classical definition of human right given by Ganston is as

follows: human right by definition is a universal moral right, something which all men, everyone, at all

time ought to have, something of which no one may be deprived of without grave affront to justice,

something which is belonging to every human being simply because they are human.

The main points of universal concept of human right are as follows.

1. All human beings are born free and equal in dignity and right.

2. Every one is entitled to all rights and freedom without distinction of any kind such as race, colour,

sex, language, religion, political or other opinion, nation or social origin, property, birth or other

status.

3. Everyone has the right to life liberty and security.

4. No one shall be held in slavery or captivity.

5. No on shall be subject to torture or to cruel, inhuman, or degrading treatment or punishment.

6. Everyone has the right to recognition everywhere as a person before the law.

7. All are equal before the law and are entitled to protection.

8. Everyone has right to an effective remedy by competent national tribunals for acts violating the

fundamental right granted to him or her by the constitution or by law.

9. No one shall be subjected to arbitrary arrest, detention, or exile.




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10. Everyone is entitled full equality and public hearing by an independent and impartial tribunal in

the determination of his rights and obligations of any criminal charges against him.

Human Right and Environment

The first draft on human right and environment was declared on May 16, 1994 at Geneva. It offers

every human being the right to enjoy a healthy, secure, and ecologically sound environment. A

sustainable society should affirm equity security and environment justice to its entire people. This draft

contains five parts:

Part I deals with human right for ecologically sound environment, sustainable development, and

peace for all. Its also emphasizes the present generation’s right to fulfill its needs to lead a dignified and good quality of life.

Part II mainly deals with human right related to an environment free from pollution and

degradation. It also emphasizes the right to enjoyment of natural ecosystems with their rich biodiversity.

Part III deals with the right of every person to environmental information, education, awareness,

and also public participation in environment decision-making.

Part IV deals with the duties to protect and preserve the environment and prevent environmental

damage.

Part V lay stress on social justice and equality with respect to use of natural recourse and

sustainable development.

VALUE EDUCATION

Though India is a land of rich cultural and spiritual heritage, a look at the current scenario poses a

number of challenges it is becoming clear that several ethical of yester years such as adherence to truth,

discipline, respect for the environment, commitment to morality, sense of duty, etc… are losing their priority. The youth of our country are confronted with misinterpreting values. One of the effective tools to

revitalize our youth and bring meaning and purpose in life is value education.

What is Value?

Values are the yardstick of beliefs that influence our behaviour and help in making of choices.

Faced with many choices man makes his decisions based upon his personal values. Besides, creating

awareness, value education helps an individual to opt for choices which would contribute towards integral

growth and ultimate happiness of the individual and society.

Objectives of Value Education

To bring about an integral personality development.

To develop right understanding among the students about their role and

responsibility towards the society and world around them.

To create an attitude of genuine appreciation for the value and respect for all forms of life.

To create a sense of consciousness among the students by exposing them to the environment

issues.

To equip the students with the capacity to take a stand as responsible human being on

“ecology and development”.




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Goals of Value Education on Environmental Issues

A clear understanding that we are an inseparable part of the bio-sphere.

A broad understanding of the bio-physical environment.

To develop a sense of responsibility to guarantee the preservation and improvement of our

environment.

A fundamental understanding of the nature of the environmental problems confronting us

today.

The 21st century is witnessing an explosion of scientific knowledge and its impact on various

social, environmental, and cultural aspects and on the economy. If we pay attention to the use of science

and technology in current times, we see that human are exploiting natural recourse to fulfill their desires

and aspirations. Therefore, natural resources are depleting day by day and cannot compete with the

desires of population, industrialization, and social and economic development has increased pollution. As

a result the planet is facing a severe crunch in terms of resources available for the present as well as the

future it can be rightly said that the world today is changed with ‘technocratic individualism’ ,which ignore the fact that natural resources are under tremendous pressure. The fast development in various

fields is leading to environmental and economic destruction. It is an act of violence against nature.

Value education is the demand of the day and it is required to ensure the available of natural

recourses like air, water, energy, forest, etc. for future generations for successful as well as sustainable

survival of human beings. Behavioral change of human society is required to preserve natural resources

for the human race tile it survives. It can be only possible if a society has well defined right and duties.

Therefore, the following duties are very important.

i. Humans should act as the custodians of all natural resource and all their possible uses must be

planned for the present as well as the future.

ii. Peaceful coexistence of all living organisms must be ensured.

iii. Necessary precaution to avoid hazardous effects of various technological developments must be

worked out and listed, so that the human race can be made a ware of all detrimental outcomes.

Value education should not only encourage the above mentioned traits in a person, but must also make

human beings understand that to save the environment for our future generations ,it is extremely

essential for a person to learn and practice the age-old traits of sacrifice and sympathy for others.

HIV/AIDS

What is HIV/ADIS?

The epidemic that has spread all over world is the acquired immune deficiency syndrome (AIDS).

It was first recognized as a disease in 1981, and is caused by human immuno-deficiency virus (HIV)

which perhaps came from chimpanzees to humans during the late 1600s.

AIDS (acquired immune deficiency syndrome), sometimes called slim disease, is a fatal illness

caused by a retrovirus known as the human immuno deficiency virus (HIV) which breaks down’s the body’s immune systems, leaving the victim vulnerable to a host of life threatening opportunistic

infections, neurological disorders, or unusual malignancies. Thus, AIDS is not one particular disease but

one that has a variety of symptoms leading to various disorders and a set of diseases.

Transmission of HIV/ADIS




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It is a transmissible disease, transmitted by the following means from one person to another. UNAIDS

suggests that gender inequality in knowledge about HIV transmission is a key factor in the high levels of

infection among African women.

If a person engages in sexual intercourse with an infected person without using a condom, they

can get infected. The sexual act can be both vaginal and anal. Sexual intercourse with a

homosexual/bisexual HIV infected person can also leads to an infection.

On sharing the needle or syringe used by / on an infected person, either for injecting drugs,

drawing blood or for any other purpose involving piercing, one can get infected. Instruments used

for piercing and tattooing also carry a small risk of infection.

Transfer of infected blood from infected person to blood receiving patients. A person can get the

infection if they are given a transfusion of infected blood.

If surgical devices like syringes and scalpels or even certain instruments, used on an infected

person, are used on another person without proper sterilization, they can transmit the infected.

Children born out of infected mother can be HIV positive because an HIV positive mother can

transmit the virus to a child during pregnancy or birth. Breast milk can also act as a transmission-

medium.

Theoretically, oral sex without condom (on men or barriers like dental dam, vaginal dams or

plastic wrap (on women) can also transmit the infection.

Many people do not develop symptoms after getting infected with HIV. Some people feel ill within

several days to a few weeks after exposure to the virus. They complain of fever, headache, tiredness and

enlarged lymph glands in the neck. These symptoms usually disappear automatically within a few weeks

and are often mistaken for some viral infection. During this time, the virus continues to multiply actively

and infects and kills cells of the immune systems. The virus destroys the cells that are the primary

infection fighters, called CD4+ or T4 cells. Once the immune system weakens, a person infected with

HIV can develop the following symptoms.

Lack of energy

Weight loss

Frequent fever and sweats

Persistent or frequent yeast infections

Persistent skin rashes or flaky skin

Short –term memory loss

Mouth, genital, or anal sores from herpes infections

AIDS is the most advanced stage of HIV infection. AIDS refers to all HIV-infected people who have

fewer than 200 CD4+ cells per micro liter of blood. Most of these conditions are infections caused by

bacteria, virus, fungi, and other organisms.

Almost all the organs is affected. Some of the common symptoms include the following:

Cough and shortness of breath

Seizures and lack of coordination

Difficulty or pain in swallowing

Mental symptoms such as confusion and forgetfulness




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Severe and persistent diarrhea

Fever

Vision loss

Nausea, abdominal cramps and vomiting

Weight loss and extreme fatigue

Coma

People with AIDS are prone to develop various cancers such as Kaposi sarcoma, cervical and cancers

of the immune system known as lymphomas.After the diagnosis of AIDS is made, the average survival

time has been estimated to be two to three years.

Protection from HIV/ADIS

There is no effective vaccine and no cure for HIV. The only way to protect oneself is prevention.

People should either abstain from having sex or use latex condoms, during oral, anal, or vaginal sex.

The risk of HIV transmission from a pregnant woman to her baby is significantly reduced if she

takes AZT during pregnancy, labour, and delivery, and her baby take it for the first six weeks of life.

Following are some of the measures that could prevent HIV infection:

i. The youth should abstain from penetrative sexual contact.

ii. Have sexual intercourse only with a faithful uninfected parent.

iii. Use sterile needles, syringes, and other instruments.

iv. Use blood that is certified HIV free.

v. Avoid pregnancy on infection with the HIV virus.

vi. General awareness and education to people about AIDS.

Misconception regarding AIDS

HIV does not spread by shaking hands, shared use of crockery, glasses, towels, etc. by donating

blood, caring for AIDS patients or HIV positive people or scratches and bites by pests, massage, physical

therapy, cosmetic treatment, acupuncture, piercing of ears, use of public toilets, swimming pools, etc.

HIV Tests

EIA or ELISA

Western blot

Radioimmunoprecipitation assay (RIPA)

Dot-blot immunobinding assay

Immunoflourescence assay

Nucleic acid testing polymerase chin reaction (PCR)

HIV in India

India had a sharp increase in the estimated number of HIV infections, from a few thousand in the

early 1990s.to a working estimate of between 38 million and 4.6 million children and adults living with

AIDS in 2006. The Indian government is criticized for clinging to the idea that the epidemic is limited to

“high-risk groups” such as sex workers, drug users and truck drivers, and that targeting them is the best

strategy; but this approach no longer reflects the reality of at least some Indian states, where the epidemic

is widely prevalent in the general population.




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In 2006, UNAIDS estimated that there were 5.6 million people living with indicated that there

were more people with HIV in India than in any other country in the world. However, the national AIDS

control organization (NACO) disputed this estimate, and claimed that effective figure was lower. In 2007,

using a more effective surveillance system, UNAID Sand NACO agreed on a new estimate between 2

million and 3.6 million people living with HIV. This puts India behind South Africa and Nigeria in

numbers living with HIV.

In terms of AIDS cases, the most recent estimate comes from August 2006, at which stage the

total number of AIDS cases reported to NACO was 124,995. Overall, around 0.36% of India’s population is living with HIV. While this may seem a low rate, India’s population is vast, so the actual number of people living with HIV is remarkably high. There are so many people living in India that a

mere 0.1% increase in HIV prevalence would increase the estimated number of people living with HIV

by over half a million.

In India, as elsewhere, AIDS is often seen as ‘someone else’s problem’ – as something that affects

people living on the margins of society, whose lifestyles are considered immoral. Even as it moves into

the general population, the HIV epidemic in misunderstood and stigmatized among the Indian public.

People living with HIV have faced violent attacks; been rejected by families, spouses and communities;

been refused medical treatment; and even, in some reported cases, denied the last rites before they die.

A 2006 study found that 25% of people living with HIV in India had been refused medical

treatment on the basis of their HIV-positive status. It also found strong evidence of stigma in the

workplace, with 74% of employees not disclosing their status to their employees for fear of

discrimination. Of the 26% who did disclose their status, 10% reported having faced prejudice as a result.

People in marginalized groups – female sex workers, hijras (transgender), and gay men – are often

stigmatized not only because of their HIV status, but also because they belong to socially excluded

groups.

WOMEN AND CHILD WELFARE

Social welfare has, in all ages, been invariably aiming at protecting individuals, groups, and

communities belonging to weaker and vulnerable sections of the society include women and children.

Women and children have an important place in every society. The condition of women in ancient

India was very good. They were placed on a pedestal and worshipped like goddesses. But later this

situation of women changed. A good society treats men and women at par with each other.

Health of children and their up bringing in a suitable atmosphere is a prerequisite for a healthy

society and a healthy nation as well. For better development of children, the following measures are

essential:

i) Nutritious food

ii) Proper education

iii) Ethical and value education

iv) Healthy environment

To create an atmosphere, in which women can acquire equal status, it is necessary to evolve a strategy

to create awareness in the society regarding women’s role responsibilities, and rights in today’s context. With this view in mind, the government of India established a department of women and




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child development in 1985 as a part of the ministry of Human Resource development, which is a

nodal agency responsible for coordinating the activities of women and child development organization

(NGOs), and the government departments. This department has four autonomous organizations:

1) National Commission of Women

2) National Institute of public cooperation and child development

3) Rashtriya mahila kosh

4) Central social welfare board

To support the pursuit of economic independence, to encourage independence of women, and to

encourage women girls facing situations of abuse by providing them with the basic necessities of shelter

and rehabilitation, the department is providing financial assistance to voluntary organizations, local bodies

and cooperative institutions state governments, etc. to construct hostels for working women, crèches for

children below the age of five years, short stay homes for women and girls, etc.

The department of women and child development was setup in the year 1985 to work for

the betterment of women and children. The department formulates plans, policies and programmes,

enact/amends legislation, guides and coordinates the efforts of both governmental and non-governmental

organizations working in the filed of women and child development. It also forms innovative

programmes for children emphasize on nutrition, pre-school education and aspects of health while those

for women relate to welfare and support services, training for employment and income generation,

awareness generation, and gender sensitization. The department has three autonomous organizations viz.

National Institute of Public Cooperation and child development (NIPCCD), Rashtriya mahila kosh

(RMK), and the central social welfare Board (CSWB).

Following is the list of important laws and rules in India to safeguard the interest of women;

o The protection of women against sexual harassment at workplace bill, 2007.

o Protection of women from Domestic Violence Act, 2005

o Dowry prohibition Act, 1961.

o Dowry prohibition rules.

o Indecent Representation of women

o The commission of sati (prevention) Act and rules

o National Commission for Women Act

Female Infanticide

Female infanticide, the prevalent form of sex-Selective infanticide, is the systematic killing of

girls at, or soon after birth. It normally occurs when a society values male children to the point that

producing a female is considered dishonourable, shameful, or an unacceptable investment by the

individuals. Female infanticide is still existent in developing countries, especially developing countries

where males are valued over females.

Child welfare

The department of women and child development has taken several steps to fulfill the needs of

children, taking special care of the girl child. Another Department in 1992 undertook a National plan of

action for the Girl child. Balika Samridhi Yojana, a scheme for prosperity of the girl child was started in

1997 with the objective of raising the overall status of the girl child by bringing about altitudinal changes




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in the families.

Child Immunization

The government has started a program, EPI, from 1971, for the control of six diseases in

children viz. TB, diphtheria, Pertussis, Tetanus, polio and Measles.

Integrated child development services (ICDS)

This scheme provides a package of services including supplementary nutrition, immunization,

medical checkups and referral and nutrition education.

In addition to the efforts made by the department of Women and child development,

government of India social welfare department of the state government, a number of national and state

level organizations are undertaking various projects and schemes towards women and child welfare in our

country.

o The juvenile justice (Care and protection of children) amendment act 2006.

o The juvenile justice (care and protection of children) act2000

o The juvenile justice (care and protection of children) rules

o The commissions for protection of child rights act 2005

o National commissions for protection of child Rights rules, 2006

o The commission for protection of child rights (Amendment) act, 2006

o Child marriage restraint act,1929

o The prohibition of child marriage act, 2006

o The infant milk substitutes act,2003

o Notification issued by the MWCD regarding enforcement of IMS amendment act

o The infant milk substitutes, feeding bottles, and infant foods (regulation of production,

supply, and distribution)act 1992

o The infant milk substitutes, feeding bottles, and infant foods (Regulation of production,

supply and distribution) Amendment act, 2003

o Notification Guidelines on infant and young child feeding

o Amendment proposed in immoral traffic (prevention) act 1956

ROLE OF INFORMATION TECHNOLOGY IN ENVIRONMENT AND HUMAN HEALTH

INTRODUTION

Today is information age and tremendous flow of information is emerging in all fields through out

of the world. Information in this competitive era is more precious than life and without information one

cannot live at all. In India, during the last decade of 20th century, Information Technology (IT) has

emerged as the most important technology revolutionizing the various spheres of life. This has created

many new avenues of employment. During this period Indians have occupied senior positions in IT

industries in developed countries like USA, UK, and Europe etc. India is a vast country endowed with

rich natural resources while facing the problems of poverty, illiteracy, population growth, environment

degradation etc.. IT is creating new possibilities to tackle problems.

What is information technology?

“Informatique” in French and “informatika” in Russian encompasses “the notion of information




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handling and it can be defined accordingly as tools and applications support through which information is

transferred, recorded, edited, stored, manipulated and disseminated with enormous quantities in the

minimum possible time”. The Working Group on IT for Masses explains “IT as a set of media, devices and services out of which proper solutions can be configured based on the needs and affordability of the

target clientele in the country”

Components of Information Technology

The use and implementation of information technology involves various components namely a)

Hardware, b) Software, c) Date, e)Storage and Communications.

Role of IT

Information technology will play a crucial role in this new operating environment by altering

methods of student evaluation, professor’s duties and responsibilities, and the central role of classroom lectures as a mode of institutions. Distance learning systems are likely to become increasingly important

as institutions use this technology to enable students to forego lectures and demonstrations in favor of

multimedia presentations. Teaching skills could change accordingly and shift from instructional delivery

to instructional design.

Application of IT in environment

Remote Sensing

It is an art (aesthetic), science (optic/sensor), and technology (rocket/orbit) of obtaining

information about the terrestrial objects (Land/water/Air) through aerial cameras/sensors from space

platforms (balloons/kites/airplanes/satellites) for preparation of thematic maps for the benefit / solving

problems of the society. The military surveyors and mapping organizations (survey of India) and urban

planner use aerial photographs of various scales (1:1000 to 1million) for the said purposes. The uses from

agriculture, forestry, earth sciences, meteorology, engineering, planning, and other discipline use the

explosive satellite data (digital and analog) for preparation of various thematic maps.

Geographic Information System (GIS)

It is a computer based information processing / thematic map preparation system using vector

(line) and raster (pixel) data. It is applied to update the maps / layers, preparation of complex thematic

maps and also for various mapping practices.

Global Positioning System (GPS)

It is a new addition in mapping of resources, survey of terrestrial positions and understanding the

location of various stationary and moving objects. It was developed for identifying / locating the ships and

later it is applied in various fields including identification of location in non-inhabited areas, higher

altitude zones, moving vehicles etc.

Meteorology

We have already come across various instances, in which lives of thousands of people were saved

due to prediction of cyclones quite in advance, giving time for safeguarding one self. Thus saving lives

and property. This could not have been achieved without use of IT. The weather is studied throughout the




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globe with the help of various weather stations on land as well as through satellites. The data generated is

processed, analyzed and projected using computer system, which are directly connected to satellites, there

by giving a chance for forewarning of probable calamities.

Application of IT in health

A part from helping in the administration of hospitals, IT is playing a key role in the health

industry. On the medical care, the IT has varied applications right from the diagnosis, where there are

latest tools like CT scans, Ultrasound Sonography etc. which use IT as their basis for diagnosis of

ailments. Most of the ICU’s (Intensive Care Units) are now using computers to monitor the progress and condition of the patient, under going treatments, apart from this, with help of IT, expert opinions from

doctors away from the place can be sought with help of IT tools like video conferences/ drugs to be used

in medical treatments.

Bioinformatics

It is an interdisciplinary field using computational techniques to analyze the biological data. With

the progress of human society being rapid, industrialization taking long leaps and at the same time human

population increasing forever, unforeseen problems are cropping up and human society has to find an

urgent answer to maintain a healthy and happy state. Problems like systemic diseases, infectious diseases

(that were once conquered) are cropping up once again, crop plants suffering from large scale destruction

due to pathogens and above all the curse and challenge to human beings from the tiniest of the creatures-

the AIDS virus; all these need a solution urgently. In the quest to find an answer to this-speed is the by

word and that is possible only with computers.

Bioinformatics became so much popular only after the release of human genomic project. Here,

once we identify all genes we can then go on studying the genes causing hereditary diseases and also can

discover drugs for that individual.

GIS and Health

Information technologies are transforming the way health care is delivered. Innovations such as

computer-based patient records, hospital information systems, computer-based decision support tools,

community health information networks, telemedicine, and new ways of distributing health

information to consumers are beginning to affect the cost, quality, and accessibility of health care.

The Role of Information Technologies discusses the synergy between information technologies

and trends in the health care delivery system as health care is brought online. It identifies some of the

opportunities to improve health care delivery through increased use of information technology, and

discusses some of the conceptual, organizational, and technical barriers that have made its adoption

uneven.

Applications of IT in Environment and Health

Environmental Information System-ENVIS

The ENVIS was set by the MOEF in 1982 as a decentralized information network for collection,

storage, retrieval and dissemination of environmental information. ENVIS network presently consists of

25 subject oriented centres known as ENVIS centres. The focal point brings out a quarterly journal,

paryavaran abstracts which are arranged under major categories like Environment Management,

Pollution, Health, Biodiversity etc.,




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