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1.
The participation of private landowners in conservation is crucial to efficient biodiversity conservation. This is especially the case in settings where the share of private ownership is large and the economic costs associated with land acquisition are high. We used probit regression analysis and historical participation data to examine the likelihood of participation of Danish forest owners in a voluntary conservation program. We used the results to spatially predict the likelihood of participation of all forest owners in Denmark. We merged spatial data on the presence of forest, cadastral information on participation contracts, and individual‐level socioeconomic information about the forest owners and their households. We included predicted participation in a probability model for species survival. Uninformed and informed (included land owner characteristics) models were then incorporated into a spatial prioritization for conservation of unmanaged forests. The choice models are based on sociodemographic data on the entire population of Danish forest owners and historical data on their participation in conservation schemes. Inclusion in the model of information on private landowners’ willingness to supply land for conservation yielded at intermediate budget levels up to 30% more expected species coverage than the uninformed prioritization scheme. Our landowner‐choice model provides an example of moving toward more implementable conservation planning.  相似文献   

2.
Abstract:  To supply ecosystem services, private landholders incur costs. Knowledge of these costs is critical for the design of conservation-payment programs. Estimating these costs accurately is difficult because the minimum acceptable payment to a potential supplier is private information. We describe how an auction of payment contracts can be designed to elicit this information during the design phase of a conservation-payment program. With an estimate of the ecosystem-service supply curve from a pilot auction, conservation planners can explore the financial, ecological, and socioeconomic consequences of alternative scaled-up programs. We demonstrate the potential of our approach in Indonesia, where soil erosion on coffee farms generates downstream ecological and economic costs. Bid data from a small-scale, uniform-price auction for soil-conservation contracts allowed estimates of the costs of a scaled-up program, the gain from integrating biophysical and economic data to target contracts, and the trade-offs between poverty alleviation and supply of ecosystem services. Our study illustrates an auction-based approach to revealing private information about the costs of supplying ecosystem services. Such information can improve the design of programs devised to protect and enhance ecosystem services.  相似文献   

3.
Many authors have proposed mechanisms to induce regulated polluting firms to truthfully reveal their private information. This paper proposes an alternative scheme in which the regulator offers each firm a menu of linear price-quantity contracts; faced with this menu, each firm′s dominant strategy is to truthfully report its private information and self-select the contract that is ex post efficient. The proposed menu schedule that is more elastic than the firm′s residual marginal damage function engenders a positive quantity effect, thereby counterbalancing the firm′s incentive to misreport prompted by the linearity of price. Due to its built-in price quantity structure, the scheme performs as designed regardless of the elasticities of marginal damage and demand functions.  相似文献   

4.
We consider contracting of a principal with an agent if multilateral externalities are present. The motivating example is that of an international climate agreement given private information about the willingness-to-pay (WTP) for emissions abatement. Due to multilateral externalities the principal uses her own emissions besides subsidies to incentivize the agent and to assure his participation. Optimal contracts equalize marginal abatement costs and, thus, can be implemented by a system of competitive permit trading. Moreover, optimal contracts can include a boundary part (i.e., the endogenous, type dependent participation constraint is binding), which is not a copy of the outside option of no contract. Compared to this outside option, a contract can increase emissions of the principal for types with a low WTP, and reduce her payoff for high types. Subsidies can be constant or even decreasing in emission reductions, and turn negative so that the agent reduces emissions and pays the principal.  相似文献   

5.
Using forests to mitigate climate change has gained much interest in science and policy discussions. We examine the evidence for carbon benefits, environmental and monetary costs, risks and trade-offs for a variety of activities in three general strategies: (1) land use change to increase forest area (afforestation) and avoid deforestation; (2) carbon management in existing forests; and (3) the use of wood as biomass energy, in place of other building materials, or in wood products for carbon storage. We found that many strategies can increase forest sector carbon mitigation above the current 162-256 Tg C/yr, and that many strategies have co-benefits such as biodiversity, water, and economic opportunities. Each strategy also has trade-offs, risks, and uncertainties including possible leakage, permanence, disturbances, and climate change effects. Because approximately 60% of the carbon lost through deforestation and harvesting from 1700 to 1935 has not yet been recovered and because some strategies store carbon in forest products or use biomass energy, the biological potential for forest sector carbon mitigation is large. Several studies suggest that using these strategies could offset as much as 10-20% of current U.S. fossil fuel emissions. To obtain such large offsets in the United States would require a combination of afforesting up to one-third of cropland or pastureland, using the equivalent of about one-half of the gross annual forest growth for biomass energy, or implementing more intensive management to increase forest growth on one-third of forestland. Such large offsets would require substantial trade-offs, such as lower agricultural production and non-carbon ecosystem services from forests. The effectiveness of activities could be diluted by negative leakage effects and increasing disturbance regimes. Because forest carbon loss contributes to increasing climate risk and because climate change may impede regeneration following disturbance, avoiding deforestation and promoting regeneration after disturbance should receive high priority as policy considerations. Policies to encourage programs or projects that influence forest carbon sequestration and offset fossil fuel emissions should also consider major items such as leakage, the cyclical nature of forest growth and regrowth, and the extensive demand for and movement of forest products globally, and other greenhouse gas effects, such as methane and nitrous oxide emissions, and recognize other environmental benefits of forests, such as biodiversity, nutrient management, and watershed protection. Activities that contribute to helping forests adapt to the effects of climate change, and which also complement forest carbon storage strategies, would be prudent.  相似文献   

6.
Incentives for wetland creation   总被引:1,自引:1,他引:1  
When information about soil quality is complete, wetland creation with a take-it-or-leave-it contract, which specifies wetland size and transfer, yields higher social benefits than if a uniform contract, which offers a payment proportional to the wetland size, had been used. This result points to a paradox because uniform contracts have been used a lot in practice.This article concentrates on the presence of asymmetric information about soil quality as a possible explanation for this paradox. It shows that the choice of instrument for wetland creation has welfare implications. Different contracts typically yield quite different social welfare surpluses and distribution between interest groups. It is not obvious, which of four contracts studied dominates when a farm characteristic affecting costs is unknown to the social planner. The probability distribution of the characteristic, the size of the excess burden, the elasticity of costs and benefits to wetland size and the cost of acquiring missing information influence the outcome.  相似文献   

7.
Cost‐effectiveness is an important aspect in the assessment of payments for environmental services (PES) initiatives. In participatory field trials with communities in Western Kenya, we combined procurement auctions for forest enrichment contracts with performance‐based payments and compared the outcomes with a baseline scenario currently used by the Kenyan Forest Service. Procurement auctions were the most cost‐effective. The competitive nature of the auction reduced contracting expenses (provision costs), and the result‐oriented payments provided additional incentives to care for the planted seedlings, resulting in their improved survival rates (service quantity). These gains clearly exceeded increases in transaction costs associated with conducting an auction. The number of income‐poor auction participants and winners was disproportionately high and local institutional buy‐in was remarkably strong. Our participatory approach may, however, require adaptations when conducted at a larger scale. Although the number of contracts we monitored was limited and prohibited the use of statistical tests, our study is one of the first to reveal the benefits of using auctions for PES in developing countries. Combinando Subastas y Pagos Basados en Desempeño en un Ensayo de Campo de Enriquecimiento de Bosques en el Oeste de Kenia  相似文献   

8.
森林碳汇的估算方法及其发展趋势   总被引:9,自引:0,他引:9  
森林生态系统是地球陆地生物圈的主体,也是陆地表面最大的碳库,在全球碳循环研究中扮演着重要角色,它通过同化作用吸收固定大气中的CO_2,抑制其浓度上升的功能对于应对气候变化问题具有积极的现实意义.准确地估算森林生态系统的碳汇储量,不仅有利于解释全球碳收支不平衡的问题,也有利于促进林业碳汇交易的快速发展.但是目前的估算方法在具有一定适用性的同时也都存在着各自的不足.评述了目前国内外应用最为广泛的样地清查法、涡度相关法及应用遥感技术的模型模拟法三种森林碳汇估算方法的发展历史和应用现状,并分析了各方法的优点与局限性.最后指出:应根据实际情况选择适合的单一方法或几种方法的结合来估算森林碳汇,以便提高估算精度;应加强森林生态系统内部联系及数据时空转换、插补的研究,并充分发挥各方法的优势,采取多种方法相结合的方式完善连续观测系统和区域监测网络的建设,降低估算方法中的不确定性,为大尺度估算提供合理的参数和数据分析基础.  相似文献   

9.
The integration of carbon sequestration value of forest ecosystems into forest management planning models has become increasingly important in sustainable forest management. This study analyses the economic effects of different minimum cutting ages on timber and carbon sequestration values for a Scots pine forest clumped mainly in older age classes in northeast Turkey. The analysis is performed by formulating three optimisation models. The objective of each model is to maximise net present value (NPV) of harvested timber, net present value of carbon sequestration and the total net present value of timber production and carbon sequestration, respectively. Results showed that increasing the minimum cutting ages by 10 years increased the NPV of timber by 10.5%. However, the current minimum cutting ages were optimal for maximizing the NPV of carbon and the sum of the NPV of timber and carbon benefits. In addition, the model outputs were found to be quite sensitive to unit carbon prices.  相似文献   

10.
Evaluating the outcomes and tracking the trajectory of biodiversity offsets is essential to demonstrating their effectiveness as a mechanism to conciliate development and conservation. We reviewed the literature to determine the principles that should underpin biodiversity offset planning and the criteria for offset evaluation at the project level. According to the literature, the core principles of equivalence, additionality, and permanence are used as criteria to evaluate conservation outcomes of offsets. We applied the criteria to evaluate offsets of a large iron ore mining project in the Atlantic Forest in Brazil. We examined equivalence in terms of the amount of area per biodiversity value affected and fauna and flora similarity, additionality in terms of landscape connectivity, and permanence in terms of guarantees to ensure protection and restoration offsets lasting outcomes. We found an offset ratio (amount of affected area:offset area) of 1:1.8 for forests and 1:2 for grasslands. Ecological equivalence (i.e., similarity between affected and offset areas) was found for forested areas, but not for ferruginous rupestrian grasslands or for fauna. Landscape metrics showed that connectivity improved relative to the preproject situation as a result of locating restoration offsets in the largest and best-connected forest patch. Permanence of offsets was addressed by establishing covenants and management measures, but financial guarantees to cover maintenance costs after mine closure were lacking. Offsets should be equivalent in type and size, provide conservation outcomes that would not be obtained without them (additionality), and be lasting (permanence). To monitor and evaluate offsets, it is necessary to determine how well these 3 principles are applied in the planning, implementation, and maintenance of offsets. Achieving measurable conservation outcomes from offsets is a long-term endeavor that requires sustained management support, and is information intensive. Thus, offsets require ongoing monitoring and evaluation as well as adaptive management.  相似文献   

11.
Self-insurance against natural disasters   总被引:1,自引:0,他引:1  
Expenditures on self-insurance to mitigate the effects of natural disasters on the value of private assets are examined in a model where individuals are partially insured against financial loss by a public relief program and where private insurance is unavailable. The model predicts that optimal private expenditures on self-insurance will be excessive or insufficient according to the nature of the technology by which individuals protect their assets. The comparative static effects of variations in the level of public compensation, individual wealth, and attitudes toward risk and the degree of environmental uncertainty on self-insurance expenditures and on the magnitude and frequency of public compensation are also characterized and their implications for remedial government policies are examined.  相似文献   

12.
Offset schemes help avoid or revert habitat loss through protection of existing habitat (avoided deforestation), through the restoration of degraded areas (natural regrowth), or both. The spatial scale of an offset scheme may influence which of these 2 outcomes is favored and is an important aspect of the scheme's design. However, how spatial scale influences the trade-offs between the preservation of existing habitat and restoration of degraded areas is poorly understood. We used the largest forest offset scheme in the world, which is part of the Brazilian Forest Code, to explore how implementation at different spatial scales may affect the outcome in terms of the area of avoided deforestation and area of regrowth. We employed a numerical simulation of trade between buyers (i.e., those who need to offset past deforestation) and sellers (i.e., landowners with exceeding native vegetation) in the Brazilian Amazon to estimate potential avoided deforestation and regrowth at different spatial scales of implementation. Allowing offsets over large spatial scales led to an area of avoided deforestation 12 times greater than regrowth, whereas restricting offsets to small spatial scales led to an area of regrowth twice as large as avoided deforestation. The greatest total area (avoided deforestation and regrowth combined) was conserved when the spatial scale of the scheme was small, especially in locations that were highly deforested. To maximize conservation gains from avoided deforestation and regrowth, the design of the Brazilian forest-offset scheme should focus on restricting the spatial scale in which offsets occur. Such a strategy could help ensure conservation benefits are localized and promote the recovery of degraded areas in the most threatened forest landscapes.  相似文献   

13.
郭月峰  姚云峰  秦富仓  祁伟 《生态环境》2013,(10):1665-1670
选择燕山典型流域6个林龄序列的小叶杨(Populus simonii)和5个林龄序列的山杏(Prunus sibirica)主要造林树种为研究对象,利用时间替代空间样地测量法量化退牧还林后生物量碳储量、凋落物碳储量和土壤碳储量及生态系统碳储量的变化规律,同时以各组成碳库-林龄序列中的最大碳储量之和作为生态系统饱和碳储量,以未退牧的天然草地生态系统碳储量作为初始植被类型的碳储量,分析总结了退牧还林对生态系统碳储量和碳循环的影响。结果表明,退牧还林后生态系统的生物量碳储量、凋落物碳储量基本随退牧年限的增加而增加,土壤碳储量随退牧年限的增加呈现先减小后增加的趋势。在没有人为干扰的情况下,9、15、18、22及29 a生小叶杨林的生态系统碳储量分别为7147.45、7461.67、7509.895、8468.375及8247.85 g·m^-2,9、15、18、22及26 a生山杏林的生态系统碳储量分别为6695.44、6700.82、8011.86、8001.92及7981.92 g·m^-2;9、15、18、22、29及36 a生小叶杨林的生态系统固碳潜力分别为757.08、1071.3、1119.53、2078.01、1857.48及1312.21 g·m^-2,9、15、18、22及26 a生山杏林的生态系统固碳潜力分别为310.45、1621.49、1611.55、1591.55及757.08 g·m^-2。长期来看,研究区退牧还林对提高生态系统碳汇能力是可观的、积极的。研究结果对提高造林对碳汇影响的估测能力提供数据支持,也为政府参与国际全球气候变化的谈判提供一个很好的案例研究和科学根据。  相似文献   

14.
Abstract: Current networks of protected areas are biased in many countries toward landscapes of low productivity. Voluntary conservation incentives have been suggested as a socially acceptable way to supplement existing networks with more productive, privately owned areas of high priority for nature conservation. The limited resources committed to nature conservation demand cost‐efficiency. Efficiency, however, depends not only on costs incurred to society from alternative ways of maintaining biodiversity but also on ecological values that can be captured. We examined the ecological efficiency of the new market‐based voluntary program to preserve forest habitats on private land in southwestern Finland. We compared sites that have become protected (10‐year contracts) in the program with managed forests, with sites that have been negotiated for protection for which no contract has been signed, and with the most ecologically valuable privately owned sites in the region that have not been offered for protection by forest owners. We surveyed sites for the amount of dead wood, wood‐decomposing fungi, and epiphytic lichens to evaluate their ecological quality. Contracted sites had more features important for overall biodiversity than managed forests and negotiated sites with no contract. These results indicate that procedures used during site selection and negotiations were appropriate and not opportunistic. The contracted sites were also as valuable in ecological terms as the best, still‐unprotected, privately owned forests in the region that have not been offered for protection. We conclude that voluntary conservation programs have the potential to yield ecologically valuable sites for protection if the site‐selection procedures are appropriate. Reliance on completely voluntary programs, however, may entail uncertainties and inadequacies, for example, in terms of spatial configuration and persistence of the ecological values. Thus, such programs may often need to be supplemented with alternative methods such as land purchase to achieve an ecologically effective network of protected sites.  相似文献   

15.
The Yellow River Delta region in China is a land area of 1,200,000 ha with rich natural resources. Adverse environmental conditions, such as low rainfall and high salinity, promote the dominance of black locust trees for afforestation. With the increase of CO2 in the atmosphere, this forest and others throughout the world have become valued for their ability to sequester and store carbon. Forests store carbon in aboveground biomass (i.e. trees), belowground biomass (i.e. roots), soils and standing litter crop (i.e. forest floor and coarse woody debris). There are well-developed methods to sample forest ecosystems, including tree inventories that are used to quantify carbon in aboveground tree biomass. Such inventories are used to estimate the types of roundwood products removed from the forest during harvesting. Based on standard plot inventories and stem analyses, carbon sequestration estimates of trees were 222.41 t ha?1 for the Yellow River Delta region accounted for 67.12% of the whole forest. Similarly, carbon storage by herbaceous matter and soil was 0.50 and 50.34 t ha?1, respectively. The results suggest that carbon sequestration in the forest ecosystem was performed by most of the forest, which plays an increasingly important role in sequestering carbon as the stand grows.  相似文献   

16.
湿地生态系统固碳潜力研究进展   总被引:13,自引:0,他引:13  
段晓男  王效科  尹弢  陈琳 《生态环境》2006,15(5):1091-1095
固碳是湿地生态系统一项重要的服务功能。文章通过对各种类型湿地的固碳量及其潜力进行分析,发现湿地的固碳潜力要高于其他类型的生态系统,维持和恢复湿地的固碳潜力对全球碳循环具有重要的意义。如果湿地遭到破坏或转为他用,其固碳能力就会随之下降,所以保护湿地是保证湿地固碳潜力优先考虑的管理措施。此外通过对泥炭湿地、沿海湿地、森林湿地和人工湿地的恢复措施及效果的分析,发现恢复和创造湿地可以恢复并增强湿地生态系统的固碳潜力,但针对湿地碳库的固碳措施需要进一步的探索和实践。  相似文献   

17.
Abstract: Privately owned lands support a large portion of the biodiversity in some areas, but procedures for identifying those private lands critical to the maintenance of biodiversity vary tremendously. We used habitat-based distribution maps in combination with population conservation goals to help identify strategic habitats on private lands in Florida. We used a vegetation map, occurrence data, and published life-history information to create habitat-based distribution maps for 179 rare taxa. We estimated the security of 130 of the taxa by overlaying public land boundaries on habitat maps and then estimating whether conservation lands satisfied a population goal of supporting at least 10 populations of approximately 200 breeding adults. The remaining taxa were evaluated in terms of number of occurrence records on conservation lands. Of the 179 taxa evaluated, existing conservation lands did not adequately protect 56. We then identified habitats on private lands that could best satisfy the minimum conservation goal or else significantly enhance the survival potential of inadequately protected taxa. Strategic habitats included a mix of large and small sites, incorporated some corridor or stepping-stone connections among habitat patches, and protected multiple species. Additional strategic habitats were identified for shorebirds, four natural plant communities, and 105 globally rare plants. The strategic habitats identified in Florida cover 1.65 million ha (12% of the land area) and would cost $8.2 billion (about 15% of Florida's annual state budget) to purchase and $122 million per year to manage. Existing conservation lands account for 3.07 million ha (22% of the land area).  相似文献   

18.
Actions to slow atmospheric accumulation of greenhouse gases also would reduce conventional air pollutants yielding “ancillary” benefits that tend to accrue locally and in the near-term. Using a detailed electricity model linked to an integrated assessment framework to value changes in human health, we find a tax of $25 per metric ton of carbon emissions would yield NOx-related health benefits of about $8 per metric ton of carbon reduced in the year 2010 (1997 dollars). Additional savings of $4–$7 accrue from reduced investment in NOx and SO2 abatement in order to comply with emission caps. Total ancillary benefits of a $25 carbon tax are $12–$14, which appear to justify the costs of a $25 tax, although marginal benefits are less than marginal costs. At a tax of $75, greater total benefits are achieved but the value per ton of carbon reductions remains roughly constant at about $12.  相似文献   

19.
20.
森林保护对减缓全球变暖有着重要意义。不同森林生态系统由于其所处地理位置不同,气候、土壤、物种构成差异很大,因此其碳汇功能也各不相同,油松是中国北方重要的森林类型之一,为了摸清贺兰山自然保护区森林碳储量,本文通过实地调查取样和室内实验测定的方法,于2011—2012年期间对宁夏贺兰山自然保护区油松林碳储量进行了取样测定,估算了其碳储量。结果表明:油松单株平均含碳率为51.91%,高于国内其他地区的阔叶树种及灌木的含碳率;经估算贺兰山油松林总有机碳储量为13.39kg.m^-2,其中立木碳储量为2.98kg.m^-2,地被层有机碳碳储量为0.86kg·m^-2,土壤层有机碳储量为9.55kg.m^-2,土壤碳储量占林分碳储量的70%以上,是油松林有机碳的主要储存库。总体来看,针叶林的固碳能力要高于阔叶林,在营造固碳林时应优先考虑针叶树种。从分布格局来看,东经105.80°~106.15°,北纬38.36°~39.00°,海拔2000~2400m的区域是油松林的主要分布区域,也是贺兰山森林有机碳的主要分布区,该区域是保护区碳平衡研究和碳汇管理应该关注的重点区域。  相似文献   

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