Mk. Pertanian Berlanjut PERTANIAN BERKELANJUTAN Oleh : Smno.agroekotek.fpub.agst2013
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Transcript of Mk. Pertanian Berlanjut PERTANIAN BERKELANJUTAN Oleh : Smno.agroekotek.fpub.agst2013
Mk. Pertanian Berlanjut
PERTANIAN BERKELANJUTAN
Oleh:Smno.agroekotek.fpub.agst2013
MAKNA SAINTIFIK “PERTANIAN”
PERTANIAN TROPIKA
IKLIM
TANAH
JASAD
AIR
DINAMIKA & RAGAM
BUDIDAYA TANAMAN
MANAJEMEN USAHATANI
PANEN & PASCAPANEN
Penanganan Hasil ; Pengolahan; Pemasaran
Sarana produksi:Tanah/lahanBenih / bibitAirPupuk/Rabuk Pestisida/ ObatTenaga Kerja
Biologi- TanamanTeknologi : Bertanam Memelihara
KEBERLANJUTAN
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PERMASALAHAN SERIUS dalam Pertanian
Semakin meningkatnya biaya dan ketergantungan thd input eksternal (bahan kimia dan
energi)
Semakin menurunnya produktivitas tanah
akibat erosi tanah dan kehilangan (pencucian)
hara dari tanah
Semakin meningkatnya
pencemaran air akibat pupuk dan
pestisida
Semakin meningkatnya ancaman residu bahan agrokimia thd kualitas dan keamanan pangan
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PERTANIAN BERKELANJUTAN itu Apa?
The word "sustain," from the Latin sustinere (sus-, from below and tenere, to hold), to
keep in existence or maintain, implies long-term support or permanence.
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PERTANIAN BERKELANJUTAN = SUSTAINABLE AGRICULTURE
“Pertanian yg dapat berkembang secara tidak terbatas ke arah manfaat yg semakin besar bagi manusia, penggunaan sumberdaya yg lebih efisien, dan berkesetimbangan dg kondisi lingkungan yang sesuai untuk manusia dan
spesies lainnya”.
Manfaat bagi
manusiaPenggunaan sumberdaya
yg efisien Lingkungan yg sesuai bagi manu-sia & spesies lain
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TIGA ELEMEN PENTING PERTANIAN BERKELANJUTAN
Income Generation
(menghasilkan pendapatan)
Food availability and consumption
(Pangan dan bahan konsumsi
lain)
Natural Resource
Conservation (Konservasi Sumberdaya
Alam)
Sustainable agriculture integrates three main
goals: environmental stewardship,
farm profitability,
and prosperous
farming communities.
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KONSEP “LOW INPUT” PERTANIAN BERKELANJUTAN
BIOLOGICAL FARMING
REGENERATIVE FARMING
ECOLOGICAL FARMING
NATURAL FARMING
BIODYNAMIC FARMING
LOW RESOURCES FARMING
AGROECOLOGICAL FARMING
ECO-AGRICULTURE ECO-FARMING
ORGANIC FARMING ALTERNATIVE
FARMING
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PRASYARAT BAGIPERTANIAN BERKELANJUTAN
1. Kualitas tanah tidak boleh rusak, topsoil tidak boleh menipis
2. Sumberdaya air tersedia harus mampu memenuhi kebutuhan tanaman, tdk berlebihan & tdk kekurangan
3. Integritas biologis dan ekologis harus dilestarikan melalui berbagai upaya pengelolaan sumberdaya genetik, siklus hara, hama tanaman, dll
4. Sistem harus menguntungkan secara ekonomis
5. Ekspektasi sosial dan norma budaya harus dipenuhi, spt kebutuhan sandang dan pangan masyarakat
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PERTANIAN BERKELANJUTAN
Sustainable agriculture integrates three main goals: environmental stewardship, farm profitability, and prosperous farming communities.
These goals have been defined by a variety of disciplines and may be looked at from the vantage point of the farmer or the consumer.
DESKRIPSI
Sustainable agriculture refers to the ability of a farm to produce food indefinitely, without causing severe or irreversible damage to ecosystem
health.
Two key issues are biophysical (the long-term effects of various practices on soil properties and processes essential for crop productivity) and socio-economic (the long-term ability of farmers to obtain inputs and manage
resources such as labor).
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PERTANIAN BERKELANJUTAN
As it pertains to agriculture, sustainable
describes farming systems that are
"capable of maintaining their productivity and usefulness to society
indefinitely. Such systems... must be
resource-conserving, socially supportive,
commercially competitive, and environmentally
sound."
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CIRI PENTING PERTANIAN BERKELANJUTAN
CROP ROTATION
Field crop - Legume -
Forage crop
NUTRIENT MANAGEMENT
Pupuk - Rabuk Kandang/Kompos -
Rabuk Hijau
Weed Control Olah tanah
Selective Herbicides
Pest Control: Biological control
Pesticide treatment
Prod. TERNAK:
Pakan hijauanRabuk kandang
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PELUANG BESAR untuk PERTANIAN BERKELANJUTAN
Internal Soil External Hydrophonic Medium
Sun: Radiasi Sumber utama energi Energi ini sbg katalis untukkonversi energi fosil
Water Utamanya hujan dan Sistem distribusi air terpusat,ditunjang air irigasi Bendungan-waduk-jaringan
Nitrogen Dihimpun dari udara Terutama dari pupuk sintetikdan di-daur ulang (pupuk buatan)
Mineral dilepaskan dari cadangan Ditambang, diolah, diimpor tanah dan di daur-ulang
Weed & pest Biologis & Mekanis Dengan pestisidacontrol
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PELUANG BESAR untuk PERTANIAN BERKELANJUTAN
Internal Soil Eksternal Hydrophonic Medium
ENERGY Sebagian dihasilkan Tergantung bahan bakaron-farm fosil
SEED Sebagian dihasilkan Semuanya/seluruhnya dibelion-farm
Management Oleh petani & masya- Sebagian dilakukan olehdecisions rakatnya produsen SAPROTAN
ANIMALS Dihasilkan secara siner- Produksi pakan di tempatgis on-farm lain yg terpisah
CROPPING- Rotasi dan diversitas MonocroppingSYSTEM sangat diutamakan
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PELUANG BESAR untuk PERTANIAN BERKELANJUTAN
Internal Soil External Hydrophonic Medium
VARIETAS Tahan thd keterbatasan Memerlukan input yang air dan kesuburan tanah banyak
LABOR Sebagian besar kerja Sebagian besar pekerjaan dilakukan rumahtangga dilakukan tenaga upahan
bertempat-tinggal on-farm
CAPITAL Sumber awal rumah- Sumber awal adalah kredit tangga & masyarakat; dan keuntungan terutama peningkatan kesejahteraan mengalir ke luar dari farm diinvestasikan secara lokal
…………...
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KOMPONEN-KOMPONENSISTEM PERTANIAN BERKELANJUTAN
Pengelolaan Kesuburan
Tanah
Pergiliran Tanaman
Innovative Cropping Systems
Bioteknologi &
Crop Breeding
Integrated Pest
Management
Weeds Management
Conservation Tillage
Feedcrop Management
Animals Roles
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• Sustainable agriculture is one that produces abundant food without depleting the earth’s resources or polluting its
environment. • It is agriculture that follows the principles of nature to
develop systems for raising crops and livestock that are, like nature, self-sustaining.
• Sustainable agriculture is also the agriculture of social values, one whose success is indistinguishable from vibrant rural communities, rich lives for families on the farms, and
wholesome food for everyone.• But in the first decade of the 21st Century, sustainable
agriculture, as a set of commonly accepted practices or a model farm economy, is still in its infancy.
PERTANIAN BERKELANJUTAN
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PRODUKSI TANAMAN
PRODUKSI TERNAK
TANAMAN PAKAN DALAM ROTASI
RABUK KANDANG
RESIDU / LIMBAH
TANAMAN
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Farming sustainably means growing crops and livestock in ways that meet three objectives simultaneously: – Economic profit – Social benefits to the farm family and the community – Environmental conservation
• Sustainability can be observed and measured; indicators that a farm or rural community is achieving the three objectives of sustainability include: economic, social, environment
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• Economic Sustainability– The family savings or net worth is consistently
going up. – The family debt is consistently going down. – The farm enterprises are consistently profitable
from year to year. – Purchase of off-farm feed and fertilizer is
decreasing. – Reliance on government payments is
decreasing.
PERTANIAN BERKELANJUTAN
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The farm enterprises are profitable from year to year:
Tumpangsari Pepaya dg padi gogo.
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• Social Sustainability– The farm supports other businesses and
families in the community. – Money circulate within the local economy. – The number of rural families is going up or
holding steady. – Young people take over their parents'
farms and continue farming. – College graduates return to the community
after graduation.
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• Environmental Sustainability– There is no bare ground. – Clean water flows in the farm's ditches and
streams. – Wildlife is abundant. – Fish are prolific in streams that flow
through the farm. –The farm landscape is diverse in vegetation.
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PERTANIAN BERKELANJUTAN
1.These three objectives are managed more as a single unit, even though we must discuss them separately.
2.The three objectives overlap constantly. For example, economic decisions affect the local community—buying from out of state instead of from a local supplier.
3.Environmental decisions affect the economics—allowing soil erosion increases the need for irrigation and more fertilizer.
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Economic Sustainability
• Selecting Profitable Enterprises to Ensure Economic Sustainability
– Economic sustainability increasingly depends on selecting profitable enterprises, sound financial planning, proactive marketing, risk management, and good overall management.
– The key for row-crop producers may be to explore income opportunities other than traditional commodity crops, such as contract growing of seeds for vegetable, rice and specialty crops.
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These specialty crops are not for
everyone;
only a certain number of
hectares of land can be grown
because of limited markets.
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Economic Sustainability
Selecting Profitable Enterprises to Ensure Economic Sustainability
– Expanding organic markets suggest another possible niche. "Alternative" crops like herbs, mushrooms or guava may be an option.
– When we try to produce a single product such as corn, or groundnuts our risk is high because "all our eggs are in one basket."
– When we integrate plant and animal agriculture we distribute overhead and risk among several enterprises.
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Economic Sustainability
Perencanaan keuangan yang komprehensif haruslah:
The holistic financial planning process provides a monthly roadmap to help people navigate through their financial year,
assured that the profit will be there at year's end.
The income is planned first, then a planned profit is allocated as the first expense item.
The remaining expense money is allocated sequentially where it will do the most good.
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Economic SustainabilityPerencanaan keuangan yang komprehensif
haruslah:
This sequential allocation requires that the farmer spend no more than necessary to run the enterprise for a year, while
preserving the planned profit.
This potent financial planning process empowers people to make decisions that are simultaneously good for the environment, the
local community, and the bottom line.
Also evaluate other financial planning tools that allow enterprise budgeting, cost calculations, partial budgeting analysis, and
these can be available from normal softwares available in the market.
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• Setiap usahatani memerlukan perencanaan pemasaran yang jelas.
• Marketing can take many forms, ranging from passive marketing to the commodity chain all the way up to marketing a retail product directly to consumers.
• Which marketing method you choose will have a profound effect on the price your product commands.
• Doing some market research is essential in order to understand your market, competition, and consumer trends, and to project potential sales volume and prices.
• Specialty and direct markets such as organic, GMO-free, and other "green" markets yield more income but require more marketing by the producer.
• Pemasaran langsung tidak berlaku untuk setiap orang .
PERTANIAN BERKELANJUTAN
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Social Sustainability
Pengambilan keputusan usahatani berdampak
langsung pada masyarakat sekitarnya .
Misalnya, the decision to expand your operation
requires the acquisition of your neighbor's farm.
To have your neighbor's farm, you must make the decision that your neighbor's farm is more important to you than
your neighbor.
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Social SustainabilityKeputusan sosial termasuk:
1. buying supplies locally rather than ordering from out of state,
2. figuring out ways to connect local consumers with your farm,
3. taking a consumer-oriented approach to production and management practices where both the farmer and consumer wins,
4. finding opportunities to ensure that neighboring communities can learn about sustainable food production.
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• Marketing strategies such as community supported agriculture (CSA), direct marketing through farmers markets or road side stalls all have a positive impact on the local community.
• When people have a choice between supporting local producers or paying a little less for the products of the industrial food system, they will often choose to support their neighbors.
• Farmers selling locally benefit from differentiating their products and services by qualities other than price.
• Fresh produce, specialty items, and locally grown and processed foods are competitive in the market place, especially when consumer education and personal contact with the farmer are part of the marketing plan.
PERTANIAN BERKELANJUTAN
Marketing strategies , direct marketing through farmers markets or road side stalls all have a
positive impact on the local community.
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PERTANIAN BERKELANJUTANSocial sustainability also
includes the quality of life of those who work and live on the
farm, including good communication, trust, and
mutual support.
Full family participation in farm planning is an indication that
the quality of life is high.
Talking openly and honestly, spending time together, a feeling of progress toward
goals, and general happiness.
Quality of life will be defined somewhat differently by each
individual and family, based on their values and goals
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Perencanaan & Pengambilan Keputusan
– Managing for three objectives simultaneously (economics, society, environment) depends on clear goal-setting and effective decision-making.
– Several good tools for decision-making, goal-setting, and whole-farm management are available to farmers.
– It is useful to assume that if your plan will not work, then develop a system for determining (as soon as possible) if it isn't working.
– For example, if the goal includes increased biodiversity, the farmer needs to know—quickly—if the grazing or cropping system being used is actually increasing the number of plant species in the area of concern.
– Monitoring is particularly important in sustainable agriculture, which relies on natural systems to replace some of the work done by input products like fertilizer and pesticides.
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PERTANIAN BERKELANJUTAN
Kemampuan mengevaluasi dan merencanakan-kembali sangat penting bagi petani
guna keberlanjutan ushataninya
When part of the plan is not working as intended, it
becomes necessary to replan.
The concept of planning-monitoring-controlling-
replanning is a key characteristic of Holistic-
Management and is referred to as the feedback loop.
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• The transition toward more sustainable farming requires not only planning and decision-making skills, but access to appropriate and helpful information.
• Fortunately, increased interest in sustainable agriculture has stimulated greater
investment in research and education. • As a result, much more usable information is
available today than ever before, accessible through various means
PERTANIAN BERKELANJUTAN
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Environmental Sustainability
• Sustainable agriculture can be viewed as ecosystem management of complex interactions among soil, water, plants, animals, climate, and people.
• The goal is to integrate all these factors into a production system that is appropriate for the environment, the people, and the economic conditions where the farm is located.
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PUPUK
PESTISIDA
TANAMANROTASI KULTIVASI
Gulma Hama Penyakit
Anorganik Organik
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PERTANIAN BERKELANJUTAN
Farms become and stay environmentally sustainable by imitating natural systems—creating a farm landscape that
mimics as closely as possible the complexity of healthy ecosystems.
The wastes of industrial agriculture (non-point-source pollution) include suspended soil, nitrates, and phosphates
in stream water, and nitrates and pesticides in ground water.
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Nature tends to function in cycles, so that waste from one process or system becomes input for another.
Industrial agriculture, in contrast, tends to function in a linear fashion similar to a factory: inputs go in one end, and products and
waste come out the other.
It is a premise of sustainable agriculture that a farm is a nature-based system, not a factory.
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1. A low dependence on external / purchased inputs
2. Menggunakan sumberdaya lokal yang “renewable”
3. Dampak lingkungan yang menguntungkan : on - farm & off - farm4. Adapted to the existing local conditions5. Long-term maintenance of productive capacity6. Biological & cultural diversity7. Knowledge of local inhabitants8. Mencukupi kebutuhan barang domestik dan barang dapat diekspor.
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SISTEM PERTANIAN SISTEM ALAMIAH
- Panen tanaman- Teknologi Pengelolaan
- Pemupukan / perabukan- Pengolahan tanah- Pengairan- Aplikasi agrokimia- Agroteknologi lainnya.
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• The simpler we try to make agriculture, the more vulnerable we become to natural disasters and marketplace changes.
• When we try to produce a single product such as wheat, corn, or soybeans we are taking on huge risk.
• If instead we diversify crops and integrate plant and animal agriculture, overhead will be spread over several enterprises, reducing risk and increasing profit.
• Table 1 offers some comparisons between two models of agriculture—farming as an industrial factory and farming as a biological system.
PERTANIAN BERKELANJUTAN
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Table 1. Comparison of the industrial and biological models of agriculture.
Industrial model Biological modelEnergy intensive Information intensiveLinear process Cyclical processFarm as factory Farm as ecosystemEnterprise separation Enterprise integrationSingle enterprise Many enterprises
Monoculture Diversity of plants and animals
Low-value products Higher value productsSingle-use equipment Multiple-use equipmentPassive marketing Active marketing
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On any farm, four major ecosystem processes are at work that, if functioning properly, will conserve the soil and
water resources and eventually reduce the overall operating costs.
Proses alamiah ini: flow, water and mineral cycles, and ecosystem dynamics— dapat diamati dan dapat dikelola.
Farm as Ecosystem: AGROEKOSISTEM
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Farm as Ecosystem: AGROEKOSISTEM
Energy flow is the non-cyclical path of solar energy (sunlight) into and through any biological system.
The natural world runs on sunlight. Our management decisions affect how much of it is captured and put to good use on the farm. (
Savory and Butterfield, 1999)
Energy flow begins when sunlight is converted into plant growth, and continues when animals consume plants, when predator
animals consume prey, and when microorganisms decompose dead plants and animals.
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Farm as Ecosystem: AGROEKOSISTEM
Some energy is lost as heat at every transfer point in the food chain.
On the farm, energy capture is enhanced by maximizing—both in space and in time—the leaf area available for photosynthesis, and
by efficiently cycling the stored solar energy through the food chain.
Off-season cover crops, perennial vegetation, and intercropping are among the tools for capturing more solar energy.
Menangkap energi-matahari dan mengubahnya menjadi produk-ekonomi merupakan sumber orisinal bagi semua
kesejahteraan
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SIKLUS AIR
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• Siklus air yang efektif dicirikan oleh tidak-adanya erosi tanah , air cepat memasuki tanah , dan
kapasitas tanah menyimpan air cukup besar .
• The water cycle is improved by management decisions that add to or maintain the groundcover
percentage and soil organic matter levels—the goal is to get as much water as possible into the soil
during each rainfall.
Farm as Ecosystem: AGROEKOSISTEM
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A surface mulch layer speeds water intake while reducing evaporation and protecting the soil from erosion.
Minimizing or eliminating tillage, growing high-residue crops and cover crops, and adding compost or manure to the soil maintains groundcover and builds organic matter.
Streams flow year-round from the slow release of water stored in the soil.
Farm as Ecosystem: AGROEKOSISTEM
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Minimizing or eliminating tillage, growing cover crops, and adding compost or manure to the soil
maintains groundcover and builds organic matter.
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Farm as Ecosystem: AGROEKOSISTEM
Such an improvement in a soil's water-holding capacity will have a beneficial effect on crop growth, especially during
droughty periods.
The results of an effective water cycle are low surface runoff, low soil surface evaporation, low
drought incidence, low flood incidence, high transpiration by plants, and high seepage of water
to underground reservoirs.
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Pengelolaan bahan organik tanah sangat
penting dalam usahatani sayuran semusim.
One study (Hudson, 1994), showed that raising the
percentage of organic matter from 1% to 2% in sandy soil increased the available water content of that soil by 60%
(from 5% of total soil volume to 8%).
Farm as Ecosystem: AGROEKOSISTEM
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DEKOMPOSISI RESIDU TANAMAN YG MISKIN N
Jumlah
Waktu
CO2
NO3- NO3- yg baru
Evolusi CO2
Mineralisasi neto
Imobilisasi neto
Nisbah C/N
60
0
20
4 - 8 minggu
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SIKLUS MINERAL
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TANAMAN
TANAH
RESIDU
PANEN
PUPUK
ATMOSFER
KEHILANGAN
60
LIAT
UREA
RABUK
BOTNH4+
NO3-
Pencucian
Jasad renik
N2, N2O NH3
Pupuk N
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Farm as Ecosystem: AGROEKOSISTEM
A well-functioning mineral cycle—the movement of nutrients from the soil through the crops and animals and back to the soil—means less need for fertilizer and feed
from off the farm.
Dalam ekosistem alamiah, unsur hara yang diperlukan oleh tanaman selalu ber-siklus secara kontinyu dengan
sedikit sekali limbah yang terbuang dan tidak memerlukan tambahan pupuk.
Ultimately, to be sustainable, we need to find ways to use the natural mineral cycle to minimize our off-farm purchase
of minerals.
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Conditions and practices that inhibit the natural mineral cycle—erosion, nutrient leaching, organic matter
depletion, selling hay or grain off the farm—tend to reduce the farm's sustainability.
Practices that enhance the mineral cycle include on-farm feeding of livestock, careful management of manure and
crop residues, use of catch crops to reduce nutrient leaching losses, and practices that prevent erosion.
Farm as Ecosystem: AGROEKOSISTEM
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SUSTAINABLE AGRIC. SYSTEM: SOIL EROSION & LAND DEGRADATION
1. Tanpa olah tanah atau olah tanah minimum2. Life mulching --- legume civer crops3. Alley cropping & agroforestry4. Supplying mulch: Erosi dan BOT 5. Fiksasi N2 dan daur ulang hara6. Minimizing fallowing7. Integrasi tanaman pangan , pepohonan, rerumputan dan
ternak8. ………….
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• An effective ecosystem dynamic is indicated by high diversity of plants and animals both above and below ground.
• "Diversity" bukan hanya banyaknya spesies , tetapi juga ragam genetik dalam suatu spesies , dan struktur umur dalam setiap populasi .
• Greater diversity produces greater stability within the system and minimizes pest problems.
• Our choices of practices and tools directly affect the level of biodiversity we have on the farm ( Table 2).
Farm as Ecosystem: AGROEKOSISTEM
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POLA TANAM DAN BIODIVERSITAS PERTANIAN
Table 2. Listing of tools by their effect on biodiversity
Increased Biodiversity
Intercropping
Crop rotation Cover crops Multispecies
grazing
Decreased Biodiversity
Monocropping Tillage Herbicides Insecticides
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PERGILIRAN TANAMAN dalam PERTANIAN BERKELANJUTAN
PADI - PADI - KEDELAIPADI - KEDELAI - JAGUNG
JAGUNG / KEDELAI - UBIKAYU
Manfaat Ekonomi
Manfaat Biologis
Manfaat Lingkungan
BIOLOGICAL STRUCTURING
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Farm as Ecosystem: AGROEKOSISTEM
The first step toward increasing biodiversity on the farm is crop rotation, which helps break weed and pest life cycles
and provides complementary fertilization among the crops in the planting sequence.
Advancing from rotation to strip intercrops brings a
higher level of biodiversity and increases sunlight capture.
Misalnya tumpangsari JAGUNG dan KEDELAI ; PISANG dan NANAS; TEBU dan RUMPUT GAJAH .
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Advancing from rotation to strip intercrops brings a higher level of biodiversity and increases sunlight
capture.
For example, Strip intercropping of sugarcane and elephant-grasses.
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Borders, windbreaks, and special plantings for natural
enemies of pests provide habitat for beneficial organisms, further
increasing biodiversity and stability.
The addition of appropriate perennial crops, shrubs, and
trees to the landscape enhances ecosystem
dynamics still further.
Farm as Ecosystem: AGROEKOSISTEM
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The addition of appropriate
perennial crops, and trees to the
landscape enhances ecosystem
dynamics still further.
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• These four ecosystem processes (energy flow, water cycle, mineral cycle, and ecosystem dynamics) function together as a whole, each one complementing the others.
• When we modify any one of these, we affect the others as well.
• When we build our farm enterprises around these processes, we are applying nature's principles to sustain the farm for our family and for future generations.
• When we fight nature's processes, we incur extra costs and create more problems, hurting ourselves and the ecosystem on which we depend.
Farm as Ecosystem: AGROEKOSISTEM
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PENERAPAN PRINSIP EKOSISTEM
When beginning the transition, the big question is how to
apply the principles of economic profitability, social enhancement,
and ecological improvement ….
in the field, in the
community, in the financial
process.
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The ultimate goal is to farm in such a way that we extract our living as the interest, while preserving the social, water,
and soil capital.
We want to ensure that our activities do not compromise the landscape and community resources over the long
term.
Now let's look at some management concepts aimed at fostering the four ecosystem processes discussed earlier.
PENERAPAN PRINSIP EKOSISTEM
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Menjaga permukaan tanah selalu tertutup vegetasi sepanjang tahun
PENERAPAN PRINSIP EKOSISTEM
Under natural conditions the soil remains covered with a skin of dead plant material, which prevents and moderates
temperature extremes, increases water penetration and storage, and enhances soil aeration.
Most importantly, the soil skin maintains soil structure and
prevents erosion by softening the impact of falling raindrops.
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Under conditions the soil remains
covered with a skin of dead plant
material, which prevents and
moderates temperature extremes,
increases water penetration and
storage, and enhances soil
aeration.
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Bare ground, on the other hand, is vulnerable to water and wind erosion, dries out more quickly, and loses
organic matter rapidly.
The major productivity costs to the farm associated with soil erosion come from the replacement of lost nutrients and reduced water holding ability, accounting for 50 to
75% of productivity loss. (Pimentel et al., 1995)
PENERAPAN PRINSIP EKOSISTEM
Menjaga permukaan tanah selalu tertutup vegetasi sepanjang tahun
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Material tanah yang terangkut oleh EROSI mengandung tiga kali lebih banyak unsur hara dibandingkan dnegan material
tanah yang tertinggal, dan sekitar 1.5 - 5 kali lebih kaya bahan organik . (Pimentel et al., 1995)
This organic matter loss not only results in reduced water holding capacity and degraded soil aggregation, but also loss of plant nutrients, which must then be replaced with
fertilizers.
Menjaga permukaan tanah selalu tertutup vegetasi sepanjang tahun
PENERAPAN PRINSIP EKOSISTEM
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The table below shows the effect of slight, moderate, and severe erosion on organic matter, soil
phosphorus level, and plant-available water on a silt loam soil in Indiana.
(Schertz et al., 1984)
Menjaga permukaan tanah selalu tertutup vegetasi sepanjang tahun
PENERAPAN PRINSIP EKOSISTEM
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Table 3. Effect of erosion on organic matter, phosphorus, and plant-available water.
Erosion level Organic matter Phophorus Plant-available
water
% Kg/ha %
Slight 3.0 69.50 7.4
Moderate 2.5 68.38 6.2
Severe 1.9 44.84 3.6
Source: Schertz et al., 1984.