VALUASI EKONOMI SUMBERDAYA LAHAN: EKSTERNALITAS

1. VALUASI EKONOMI SUMBERDAYA LAHAN: EKSTERNALITAS Diabstraksikan : soemarno, jtnhfpub 2014

2. EKSTERNALITAS Dalamprosesproduksipertanian, masukan-masukan yang berupa material, tekno¬logi, menejemendanunsur-unsur agro ekologiakandiprosesuntukmenghasilkankeluaran-keluaran yang berupahasil-hasiltanamandanternak. Hasil-hasilsampingandanlimbahdariprosesproduksitersebutdapatberupahasilsedimen, hasil air, danbahan-bahankimia yang dapatmenjadipencemarlingkungan. Limbahinibiasanyadiangkutkeluardarisistemproduksidanmenimbulkanbiayaeksternaldanefekeksternalitas. Biasanyasistemproduksipertaniandidaerahhulusungaimempunyaiefekeksternal yang cukupluasdanakandideritaolehmasyarakatdidaerahbawah. Dalamsuatudaerahaliransungai yang mempunyaibangunanpengairansepertibendungan, wadukdanjaringanirigasi, efekeksternalitastersebutmenjadisemakinserius, karenadapatmengancamkelestarianbangunan-bangunantersebut. DiunduhdariSumber: http://lecture.ub.ac.id/anggota/marno/activity/16054/ .................... 5/11/2012 .

3. EKSTERNALITAS “Eksternalitas” timbulkalaukegiatanproduksi (dankonsumsi) memilikipengaruh yang tidakdiharapkan (tidaklangsung) terhadapprodusendan /ataukonsumen lain. “Eksternalitaspositif” terjadikalaukegiatan yang dilakukanolehseseorangmemberikanmanfaatpadapihak lain tanpamelaluimekanismepasar. “Eksternalitasnegatif” terjadikalaukegiatanolehindividumenghasilkandampak yang merugikanpihak lain. Pencemaran air sungaiatau air sumurdapatditimbulkanolehprosesproduksipertanian yang berasaldaripenggunaanpestisidadanpupuk. Adanyaeksternalitasmenyebabkanterjadinyaperbedaanantaramanfaat (biaya ) sosialdenganmanfaat (biaya) privat. Perbedaanmanfaat (biaya ) iniberkaitandneganalokasisumberdaya yang tidakefisien. Pihak yang menyebabkaneksternalitastidakmemilikidoronganuntukmenanggungdampakdarikegiatannya yang dideritaolehpihak lain. DiunduhdariSumber: http://dickyhendramulyadi.blog.com/2012/02/04/eksternalitas-lingkungan/.................... 5/11/2012 .

4. EKSTERNALITAS EROSI TANAH. “Erositanah” merupakanprosesterangkutnya material tanahatausedimenolehaliran air yang terjadidipermukaantanah. Kerusakan yang dialamiolehtanahditempat yang adaerosia.l.: Kehilanganunsurharadanbahanorganik. Menurunnyakapasitasinfiltrasi (kemampuantanahuntukmeresapkan air) dankemampuantanahmenyimpan air. Meningkatnyakepadatandanketahananpenetrasitanah. Berkurangnyakemantapanstrukturtanah yang padaakhirnyamenyebabkanmemburuknyapertumbuhantanamandanmenurunnyaproduktifitas. Eksternalitaslingkunganakibaterositanaha.l.: Sedimentasidanpendangkalanwaduk Tertimbunnya (sedimentasi) jaringanirigasi. Memburuknyakualitas air sungai , air sumur, air permukaanlainnya, Kerugianekosistemperairan. DiunduhdariSumber: http://ryniforfun.blogspot.com/2010/03/erosi-tanah-dampaknya-bagi-kehidupan.html.................... 5/11/2012 .

5. EKSTERNALITAS 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. DiunduhdariSumber: .................... 31/10/2012 .

6. EXTERNALITY 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. In 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. DiunduhdariSumber: http://www.compilerpress.ca/ElementalEconomics/271%20Environmental/Econ%20271%202.0%20Environmental%20Economics%20b.htm .................... 5/11/2012 .

7. EXTERNAL BENEFIT

8. EXTERNAL COST MSC = marginal social cost; MC = marginal cost MSC = MC + MEC MEC = marginal external cost MPC = marginal private cost MC = MPC DiunduhdariSumber: .................... 5/11/2012 .

9. EKSTERNAL COST – IN-EFISIENSI Adanyabiayaeksternalmengakibatkan in-efisiensidalamprosesproduksi

10. NEGATIVE EXTERNALITIES 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. DiunduhdariSumber: http://cnx.org/content/m38612/latest/.................... 5/11/2012 .

11. Over-production with a negative externality 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 . Ps Pp Qs Qp DiunduhdariSumber: http://www.grin.com/en/doc/230776/a-computable-general-equilibrium-analysis-of-aggregates-materials-recycling.................... 5/11/2012 .

12. Pigouvian tax applied to a negative externality 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. DiunduhdariSumber: .................... 5/11/2012 .

13. KerusakanLingkungansebagaiEksternalitasNegatif Some 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. 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. DiunduhdariSumber: http://www.tcd.ie/Economics/staff/amtthews/FoodPolicy/LectureTopics/Environment/Lecture20.htm .................... 5/11/2012 .

14. DivergensiBiayaSosialdanBiayaPrivat 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. DiunduhdariSumber: http://www.sciencedirect.com/science/article/pii/S0301420704000340 .................... 5/11/2012 .

15. Optimal level of soil quality and soil costs. DiunduhdariSumber: http://www.sciencedirect.com/science/article/pii/S0301420704000340 .................... 5/11/2012 .