VALUASI EKONOMI SUMBERDAYA

LAHAN:EKSTERNALITAS

Diabstraksikan : soemarno, jtnh fpub 2014

EKSTERNALITAS

Diunduh dari Sumber: http://lecture.ub.ac.id/anggota/marno/activity/16054/ .................... 5/11/2012 .

Dalam proses produksi pertanian, masukan-masukan yang berupa material, tekno¬logi, menejemen dan unsur-unsur agro ekologi akan diproses untuk menghasilkan keluaran-

keluaran yang berupa hasil-hasil tanaman dan ternak.

Hasil-hasil sampingan dan limbah dari proses produksi tersebut dapat berupa hasil sedimen, hasil air, dan bahan-bahan kimia yang dapat menjadi pencemar lingkungan.

Limbah ini biasanya diangkut ke luar dari sistem produksi dan menimbulkan biaya eksternal dan efek eksternalitas.

Biasanya sistem produksi pertanian di daerah hulu sungai mempunyai efek eksternal yang cukup luas dan akan diderita oleh masyarakat di daerah bawah.

Dalam suatu daerah aliran sungai yang mempunyai bangunan pengairan seperti bendungan, waduk dan jaringan irigasi, efek eksternalitas tersebut menjadi semakin

serius, karena dapat mengancam kelestarian bangunan-bangunan tersebut.

EKSTERNALITAS

Diunduh dari Sumber: http://dickyhendramulyadi.blog.com/2012/02/04/eksternalitas-lingkungan/.................... 5/11/2012 .

“Eksternalitas” timbul kalau kegiatan produksi (dan konsumsi) memiliki pengaruh yang tidak diharapkan (tidak langsung) terhadap produsen dan

/atau konsumen lain. “Eksternalitas positif” terjadi kalau kegiatan yang dilakukan oleh seseorang

memberikan manfaat pada pihak lain tanpa melalui mekanisme pasar. “Eksternalitas negatif” terjadi kalau kegiatan oleh individu menghasilkan

dampak yang merugikan pihak lain. Pencemaran air sungai atau air sumur dapat ditimbulkan oleh proses

produksi pertanian yang berasal dari penggunaan pestisida dan pupuk.

Adanya eksternalitas menyebabkan terjadinya perbedaan antara manfaat (biaya ) sosial dengan manfaat (biaya) privat. Perbedaan manfaat (biaya ) ini

berkaitan dnegan alokasi sumberdaya yang tidak efisien. Pihak yang menyebabkan eksternalitas tidak memiliki dorongan untuk menanggung

dampak dari kegiatannya yang diderita oleh pihak lain.

EKSTERNALITAS EROSI TANAH.

Diunduh dari Sumber: http://ryniforfun.blogspot.com/2010/03/erosi-tanah-dampaknya-bagi-kehidupan.html.................... 5/11/2012 .

“Erosi tanah” merupakan proses terangkutnya material tanah atau sedimen oleh aliran air yang terjadi di permukaan tanah.

Kerusakan yang dialami oleh tanah di tempat yang ada erosi a.l.:1. Kehilangan unsur hara dan bahan organik.2. Menurunnya kapasitas infiltrasi (kemampuan tanah untuk meresapkan air) dan

kemampuan tanah menyimpan air.3. Meningkatnya kepadatan dan ketahanan penetrasi tanah.4. Berkurangnya kemantapan struktur tanah yang pada akhirnya menyebabkan

memburuknya pertumbuhan tanaman dan menurunnya produktifitas.

Eksternalitas lingkungan akibat erosi tanah a.l.:5. Sedimentasi dan pendangkalan waduk6. Tertimbunnya (sedimentasi) jaringan irigasi.7. Memburuknya kualitas air sungai , air sumur, air permukaan lainnya,8. Kerugian ekosistem perairan.

EKSTERNALITAS

Diunduh dari Sumber: .................... 31/10/2012 .

The problem is that the way owners use their land may affect others. If they dump garbage on their neighbors' land, clearly they are infringing upon

others' rights. But how about if they burn garbage and the resulting smoke blows onto nearby properties?

What if they pollute a stream and it ends up affecting everyone's water source, or flush sewage away and it ends up in an ecologically stressed bay? Although the field of economics traditionally likes to deal with items that can be easily demarcated, quantified, and tagged with ownership, this becomes

difficult when dealing with our shared ecosystems.

Economics has dealt with this largely by labeling such items externalities, costs for which the responsible party does not pay.

It then becomes up to the community, and usually the government, to decide how to deal with externalities.

Diunduh dari Sumber: http://www.compilerpress.ca/ElementalEconomics/271%20Environmental/Econ%20271%202.0%20Environmental%20Economics%20b.htm .................... 5/11/2012 .

Until now we have assumed that market

price includes or 'internalizes' all relevant costs and benefits. This

means the consumer captures all benefits and the producer pays all the

costs. An externality refers to costs and benefits that

are not captured by market price for

whatever reasons, i.e., they are external to

market price.

EXTERNALITYIn effect, the market demand curve reflects only marginal private benefits (MPB) of consumers

but not the external benefits accruing to society. When such external benefits are added,

vertically, we derive the marginal social benefit curve (MSB) inclusive of both private and public

benefits. Similarly, the market supply curve reflects only

marginal private costs (MPC) but not costs external to the firm’s accounting, e.g., pollution

that society must pay. When social costs are added, vertically, to the supply curve we derive the marginal social cost (MSC) curve inclusive of

both private and public costs.

EXTERNAL BENEFIT

Diunduh dari Sumber: .................... 5/11/2012 .

MSC = MC + MEC

EXTERNAL COSTMSC = marginal social cost; MC = marginal

cost

MEC = marginal external costMPC = marginal private cost

MC = MPC

EKSTERNAL COST – IN-EFISIENSI

Adanya biaya eksternal mengakibatkan in-efisiensi

dalam proses produksi

Diunduh dari Sumber: http://cnx.org/content/m38612/latest/.................... 5/11/2012 .

A negative externality is a cost associated with an action that is

not borne by the person who chooses to take that action.

Inefficiency from Negative Externality

When there is a negative externality, the market equilibrates

where the total social marginal cost exceeds the marginal benefit

of the last unit of a good and society is not as well off as it could

be if less were produced.

NEGATIVE EXTERNALITIES

Diunduh dari Sumber: http://www.grin.com/en/doc/230776/a-computable-general-equilibrium-analysis-of-aggregates-materials-recycling.................... 5/11/2012 .

The failure to internalize the negative externality results in diminished social well-

being.

The over-production occurs when the external costs of waste disposal in the

community are ignored (not internalized).

In this figure, the private profit- maximizing quantity of landfill deposits produced (Qp )

are greater than the socially optimal production that occurs when the external

costs are included (Q s ). The amount of overproduction is equal to the distance from Qp to Qs . In order to account

for the external costs imposed on the community from producing additional

(aggregates) deposits into the landfill, it is important to increase the costs of these

deposits from Pp to Ps .

Over-production with a negative externality

Pp

Ps

QpQs

Diunduh dari Sumber: .................... 5/11/2012 .

What happens when one form of government intervention (a Pigouvian tax on the disposal of aggregates) is

implemented. With a Pigouvian tax, the tax is set

equal to the marginal external costs at the socially optimal point of

production.

In this case, the tax on deposits elevates the price of disposal, leading

to a reduction in the amount of deposits.

A reduction of deposits into the local landfill would most likely result from

corresponding reductions in the amount of aggregates waste created

in the production process or from finding alternative means of disposal

of the waste.

Pigouvian tax applied to a negative externality

Diunduh dari Sumber: http://www.tcd.ie/Economics/staff/amtthews/FoodPolicy/LectureTopics/Environment/Lecture20.htm .................... 5/11/2012 .

These environmental costs are externalised, and there is thus divergence between the

marginal private cost of production (to which the producer responds) and the marginal

social cost of production (which determines the socially optimal level of production).

Over-production of farm output which causes environmental damage is shown in the

following diagram. The farmer would produce at Q1 where his

marginal private cost equals marginal revenue, although the socially efficient level of output is Qo which takes into account the

additional social costs of agricultural production.

Kerusakan Lingkungan sebagai Eksternalitas NegatifSome adverse environmental impacts may be internalised into a farmer's decision-making process, e.g. soil erosion, as this may impact on the revenue-generating potential of the farm in the future.

However, the problem with many environmental impacts is that the costs are not borne by the producer because there is no mechanism to price the damage being done and require the producer

to pay.

Diunduh dari Sumber: http://www.sciencedirect.com/science/article/pii/S0301420704000340 .................... 5/11/2012 .

The paper defines the concept of land degradation and costs and effects of soil erosion. Through the concept of

optimal levels of soil erosion, a conceptual model of the social costs of

soil degradation is elaborated. The discussion focuses on the

measurement aspects of the economic scarcity of soil in the agriculture sector. Reliable estimates of the true impacts of soil degradation can only be made if

data on marginal damage costs and marginal conservation costs are

available. The different scarcity indicators are

evaluated and competitive land rental prices are considered as appropriate in

indicating soil scarcity in agriculture.

Divergensi Biaya Sosial dan Biaya Privat

Optimal level of soil quality and soil costs.

Diunduh dari Sumber: http://www.sciencedirect.com/science/article/pii/S0301420704000340 .................... 5/11/2012 .