首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Policymakers seeking to modify financial incentives to increase the flows of ecosystem services in and around tropical moist forests must consider where to focus their attention and what collection of incentives can effectively achieve policy objectives. In most cases, policymakers focus on extensively forested areas where the flows of ecosystem services between agriculture and the environment is generally characterized by massive flows of carbon and soil nutrients from forests to agriculture. In these forest margin areas the stock of primary forest is eventually exhausted and the cheap ingredients provided by nature to agriculture become increasingly scarce. At this point, policy interest generally wanes, and agriculture and the environment begin slow declines in ecosystem service exchange, often with negative consequences for rural poverty. How does one promote increased flows of ecosystem services from agricultural lands without increasing poverty when forests and soils have been depleted? Can the standard instruments, e.g., payments for ecosystem services, be effective in such situations, and if so, do the costs to society of securing these services increase? Here we focus on the flows of ecosystem services at the end of the cycle of converting primary forest to agriculture. Primary data from the Bragantina area in the southeastern Brazilian Amazon, an area cleared of primary forest decades ago, are used to characterize smallholder production systems, to describe the flows of ecosystem services into and from these systems, and to develop a bioeconomic model of smallholder agriculture capable of predicting the effects of several types of policy action on ecosystem services provided by and to agriculture, and on-farm household incomes and food self-reliance. Of particular interest is the Proambiente Pilot Program in Brazil, which uses smallholder payment schemes to induce farmers to manage land and forest resources in ways that generate more ecosystem services. Baseline results suggest that smallholder agriculture leads to a gradual loss of ecosystem services (mainly above-ground and root carbon) provided by secondary forest fallows, and that reduction in fallow age leads to reductions in plant diversity. Intensifying agricultural activities accelerates this process, but considerably increases smallholder incomes. Paying farmers for ecosystem services linked to the retention of secondary forests and the Proambiente program both increase area in forest fallow, but the latter substantially reduces farm income because of input use restrictions. In general, programs aiming to promote the production of ecosystem services should not limit farmers' choices of ways to provide them. Employment and food self-reliance issues associated with policy options for increasing on-farm stocks of carbon and plant biodiversity are also explored.  相似文献   

2.
Analyses were carried out on financial compensation to avoid loss of tropical forests and related carbon (C) emissions when marginal financial yield declined for land-use options with extended areas, and when a risk-averting perspective (modeled according to financial theory around the capital asset pricing model) is assumed. The approach in this study was to consider natural forest, forest plantation, pasture, and cropland simultaneously to investigate how an optimized land-use distribution may reduce the amount of compensation necessary to avoid C emissions from forest loss.The financial compensations derived were as high as US$ 176 per hectare per year when comparing natural forests only with the most profitable alternative (croplands). However, compensation decreased to US$ 124 for risk-neutral decision-makers, who would strive for optimized land-use allocation, and to only US$ 47 per hectare per year for risk-avoiders, who would look to maximize the reward-to-variability ratio. Sensitivity analyses indicated that the compensation under risk-aversion increased much less than under risk-ignoring when increased productivity of agricultural land-use or growing demand for agricultural products was simulated. It was concluded that considering appropriate diversification strategies and the well documented human behavior to avoid risks is an important step in developing cost-effective compensation policies.  相似文献   

3.
Climatic changes will affect the dynamics of a forest ecosystem. Consequently, carbon sequestration costs can only be estimated correctly if changes in climatic conditions are considered. This article determines the changes in mitigation costs of an optimal forest management regime in the presence of climatic changes and varying prices, and takes account of substitution processes between timber production and carbon sequestration at the stand level. The study demonstrates that in the presence of climate change the sequestration costs per ton of carbon increase with higher amounts of carbon sequestered per hectare. This finding can be used to identify a threshold for the amount of sequestered carbon per hectare below which the costs of carbon sequestration are hardly influenced by climate change.  相似文献   

4.
In a recent paper in this journal Nuñez et al. [Nuñez, D., L. Nahuelhual, and C. Oyarzun, 2005. Forest and water: the value of native temperate forests in supplying water for human consumption. Ecological Economics 58: 606-616] presented a model to estimate the economic value of Chilean temperate forests in their function to contribute to maintain fresh water supply. We discuss and correct the estimated values of ecosystem services per household and per hectare.  相似文献   

5.
Biodiversity loss is a problem of global concern affecting ecosystem functioning and services provided to humans. The Millennium Ecosystem Assessment is built on a conceptual framework that links biodiversity with the services ecosystems provide to society and human welfare. Numerous empirical studies have measured ecosystem goods and services in terms of economic values; however, less evidence is available of the indirect effect of biodiversity on these values. Based on this, we first compile market and non-market forest valuation studies and, secondly, explore the potential of an econometric modelling exercise by conducting a worldwide meta-analysis. This exercise aims to highlight the role of biodiversity indicators on valuation. In this way, we can study the underlying transmission mechanisms that explain to what extent biodiversity is related to human welfare. Furthermore, we also propose to evaluate the magnitudes of the respective distributional impacts, including the different ecosystem goods and services under consideration. Our results show that biodiversity indicators may have an underlying effect on forest ecosystem values, which also depend on the type of ecosystem services. Lastly, the results are discussed and analysed with respect to their policy implications concerning biodiversity conservation.  相似文献   

6.
This study uses biophysical values derived for the Prairie Pothole Region (PPR) of North and South Dakota, in conjunction with value transfer methods, to assess environmental and economic tradeoffs under different policy-relevant land-use scenarios over a 20-year period. The ecosystem service valuation is carried out by comparing the biophysical and economic values of three focal services (i.e. carbon sequestration, reduction in sedimentation, and waterfowl production) across three focal land uses in the region [i.e. native prairie grasslands, lands enrolled in the Conservation Reserve and Wetlands Reserve Programs (CRP/WRP), and cropland]. This study finds that CRP/WRP lands cannot mitigate (hectare for hectare) the loss of native prairie from a social welfare standpoint. Land use scenarios where native prairie loss was minimized, and CRP/WRP lands were increased, provided the most societal benefit. The scenario modeling projected native prairie conversion to cropland over the next 20 years would result in a social welfare loss valued at over $4 billion when considering the study's three ecosystem services, and a net loss of about $3.4 billion when reductions in commodity production are accounted for.  相似文献   

7.
Deforestation and forest degradation are estimated to account for between 12% and 20% of annual greenhouse gas emissions and in the 1990s (largely in the developing world) released about 5.8 Gt per year, which was bigger than all forms of transport combined. The idea behind REDD + is that payments for sequestering carbon can tip the economic balance away from loss of forests and in the process yield climate benefits. Recent analysis has suggested that developing country carbon sequestration can effectively compete with other climate investments as part of a cost effective climate policy.This paper focuses on opportunities and complications associated with bringing community-controlled forests into REDD +. About 25% of developing country forests are community controlled and therefore it is difficult to envision a successful REDD + without coming to terms with community controlled forests. It is widely agreed that REDD + offers opportunities to bring value to developing country forests, but there are also concerns driven by worries related to insecure and poorly defined community forest tenure, informed by often long histories of government unwillingness to meaningfully devolve to communities. Further, communities are complicated systems and it is therefore also of concern that REDD + could destabilize existing well-functioning community forestry systems.  相似文献   

8.
Valuing global public goods like the Amazon rainforest by stated preference surveys of a representative sample of the global population would be very costly and time consuming. We explore the use of the Delphi Method in contingent valuation (CV) by asking a panel of 49 European environmental valuation experts in two rounds what they think would be the result if a European CV survey of Amazon Rainforest protection plans was conducted. The experts’ best guess for the mean willingness-to-pay (WTP) by European households for preserving the current Amazon Rainforest, and thus avoiding a predicted loss in forest area by 2050 from currently 85% to 60% of the original forest in the 1970s, was 28 € per household annually as an additional income tax. Aggregated over all European households this amounts to about 8.4 billion € annually. This preliminary estimate indicate that WTP of distant beneficiaries is substantial, and could justify preservation of global ecosystem services where aggregated benefits of the local population often do not exceed the opportunity costs of preservation in terms of lost income from commercial activities. The income elasticity of WTP with respect to per-capita income in the European countries is 0.5–0.6. Recognizing the limitations and assumptions of the Delphi CV method, it could still be a time saving and cost-effective benefit transfer tool for providing international donors with much needed order-of-magnitude estimates of the non-use value of ecosystem services of global significance.  相似文献   

9.
Researchers generally express the local value of tropical rain forests in dollars/ha/year. The approach is problematic because it produces low values to local users, underestimating the importance of the forest expressed as a share of household consumption or earnings. Here we contribute to valuation studies of rain forests by estimating the financial importance of the forest measured in three ways: (1) the contribution of forests to annual household consumption and (2) earnings; and (3) the value of a hectare of rain forest to villagers measured through the biological goods consumed and sold. We collected panel data on consumption and earnings from 81 households in four villages of two Amerindian societies in two nations (Tsimane’, Bolivia; Tawahka, Honduras). Analyses suggest: (1) forests account for a large share of household consumption (median 38.5%; range 14.65–53.11%); (2) forests contribute more to household consumption than to household earnings (median 22.69%; range 16.56–44.81%); (3) the relative contribution of forests to household consumption and earnings falls among villages closer to towns; and (4) the range of values/year of rain forest/ha is US$7.10–9.70 using 1999 dollars or US$18.46–46.56 using purchasing power parity indexes, below previous estimates. Results show much variation in forest values; valuation methods and stakeholder perspectives affect the variation. Given the variation, a useful strategy to promote forest conservation would transfer income to villagers to compensate them for non-local forest values.  相似文献   

10.
Agricultural expansion into tropical forests is believed to bring local economic benefits at the expense of global environmental costs. The resulting tension is reflected in Brazilian government policy. The national agrarian reform program has settled farm families in the Amazon region since the 1970s, with the expectation that they will clear forests in order to farm the land. On the other hand, recent Brazilian policy initiatives seek to reduce deforestation to mitigate climate change. We contribute to the policy debate that surrounds these dual goals for the Amazon by estimating the marginal effects of new agricultural land on the full income and assets of farm settlers over a 13-year period from 1996 to 2009. Using micro panel data from agrarian settlements where forest was being rapidly cleared, and controlling for factors that would otherwise confound the relationship, we estimate the effect of converting forest to agriculture on total household income to estimate the opportunity cost of conserving forest. Our measure of income reflects any re-allocation of resources by utility maximizing households and any productivity effects due to loss of forest ecosystem services. The estimated effect of new agricultural land on income is positive, but small relative to the income per hectare of previously cleared land. However, we show that income increases investment in physical assets, which raises households’ income generating capacity and future accumulation of assets. Thus, while there is only a small immediate income gain from clearing more forest, the long-term effects on wealth are still substantial. This demonstrates that given the right conditions, conversion of forest to agricultural land can be an impetus for asset accumulation by smallholders. It also highlights the importance of considering the indirect and long-term welfare benefits of new agricultural land when assessing the opportunity costs of forest conservation.  相似文献   

11.
Peatlands are an important multipurpose ecosystem, supporting huge quantities of biomass and peat soil carbon. A time series of Japanese Earth Resource Satellite-1 (JERS-1) L-band Synthetic Aperture Radar (SAR) data was employed to monitor two dynamic ecosystem processes; deforestation and inundation patterns. Using a change detection analysis for three images acquired during dry seasons of 1994, 1997 and 1998, we detected the deforestation that has occurred in the region due to the anthropogenic and natural causes. At a threshold of ±2 dB change in backscattering response, an area of about 98 km2 of these forests was found to have been cleared during 1994–1997 for conversion to cultivatable lands. However, the agricultural crops miserably failed to grow on these cleared lands because of the adverse water and soil chemistry conditions. The deliberate draining of these lands, by laying and extension of a huge network of canals, created congenial ecological conditions for the spread of forest fires, particularly during the 1997 El Niño period. An area of 250 km2 of forests was thus detected to have been destroyed by these fires between September 1997 and January 1998. These deforested lands are rapidly regenerating since their abandonment and the regenerating carbon stocks were simulated using the CENTURY ecosystem dynamics model. Furthermore, the L-band SAR was able to detect the pixel-wise seasonal and spatial inundation information for particular forest types where the transmissivity of the L-band SAR signals was quite significant. These forest types corresponded to comparatively low biomass areas. The SAR derived information about these two important dynamic processes would be useful for improving the accuracy of modelling the spatial and temporal distribution of the carbon and other trace gases in these ecosystems.  相似文献   

12.
A GIS-based approach was designed to spatially estimate direct use value of ecosystem services and to map results for a case study at county scale. The approach highlights the use of GIS to collect data, perform spatial analysis, and map economic values of ecosystem services. Three key steps of spatial valuation for agricultural products, forest products, and tourism services were illustrated in the GIS-based technical framework. We applied this approach to the Tiantai County (1423.8 km2) in Zhejiang province of southeast China. Selected components of natural products and tourism services in the case area were mapped as data layers in GIS, with each layer containing monetary values for every 25 m cell. The total direct use value of ecosystem services was estimated in RMB to be approximately 538 million Yuan in 2005 (Chinese currency, 8.2 Yuan = US$1), of which agricultural products, forest products and tourism services accounted for 65%, 30% and 5%, respectively. The critical areas for management purpose were identified depending on the heterogeneity of direct use services learned from the case study. The spatially explicit measures provide a mechanism for incorporating spatial context into ecosystem services evaluation. Based on the present GIS-based approach and case study, the suggestions and implications for local resources protection and eco-environmental management were extensively discussed. The work was expected to highlight research avenues to advance the ecosystem services framework as an operational basis for regional ecosystem-based management.  相似文献   

13.
There is currently substantial interest in valuing various services provided by different ecosystems. Concurrently economists have ascribed substantial effort on expanding traditional forest accounting systems by environmental services. This paper contributes to curtailing the existing gap between green accounting theory and applications for valuing forest ecosystem services. The multitude of links between forest ecosystem services and economy are characterized by the theoretical model for forest-economy interactions. By utilizing recently updated data we also incorporate empirical value estimates of these services comparable to other goods into Finnish forest accounting system. Finally, we discuss some problems encountered and clarify the interpretation of some value estimates incorporated to national forest account.  相似文献   

14.
集体林区生态公益林产权市场化探讨   总被引:1,自引:0,他引:1  
在阐述生态公益林产权市场化可能的类型的基础上,分析当前阻碍集体林区生态公益林产权市场运行的主要因素,提出促进生态公益林产权市场化运行的对策建议,主要包括明晰和优化公益林产权,加强公益林生态服务功能价值评估,创建有利于公益林产权市场发展的外部环境。  相似文献   

15.
This paper presents a Choice Modeling application of forest goods and services valuation for an afforestation program in the Northeast of Spain. The results from a random parameter logit model reveal that, on average, individuals would annually pay an average of 11.79 euros for the forests to sequester 68,000 tones of CO2, 0.12 euros for delaying the loss of land productivity for ten years, and 6.33 euros from picnic users for being allowed to picnic in the new forests. On the other hand, individuals would experience a loss in welfare equivalent to − 9.67 euros if four-wheel driving is allowed in the new forests. Finally, being allowed to pick mushrooms in the new forests is valued at an average of 12.82 euros by those who live in rural areas.  相似文献   

16.
《Ecological Economics》2007,60(4):462-476
In this paper, we account for forest wealth in India. Changes in the timber and carbon wealth embodied in these forests are related to important green national accounting aggregates such as genuine saving and the change in wealth per capita. Important accounting issues include the timing of carbon releases that occur when forests are disturbed, as well as the valuation of these releases. Our empirical findings suggest that while India's forest wealth is substantial, net changes in this wealth are arguably not so large at least in relation to GNP. However, when viewed in the context of the wealth-diluting effects of population growth this implies a far larger additional savings effort is required to cover the (net) loss in forest values than otherwise appears to be the case. Finally, we examine ways in which the accounting approach that we adopt can be reconciled with approaches which stress conserving forest wealth.  相似文献   

17.
National accounting issues related to forest resources have attracted much attention recently. The net-depletion method, the most popular method for estimating aggregate changes in the value of timber stocks, tends to overstate both the depreciation of mature forests due to harvests and the appreciation of immature forests due to growth. Alternative, correct methods, which I term the net-price and El Serafy variations, can be derived from an asset valuation model that takes forest age into account. An empirical example indicates that estimates from the net-depletion method can deviate from actual values by up to 40 percent for some age classes.  相似文献   

18.
Ecosystem services valuation has achieved considerable prominence in research and policy circles in recent years. This paper reviews the studies that have tried to estimate the value of forest ecosystem services. Broadly, this study addresses the following questions: (1) What insights do these studies provide on the value of forest ecosystems? (2) What lessons do they offer from an economic and policy perspective? (3) What are the shortcomings of the existing studies, and what are the challenges and issues for future research? Evidence from a cross section of forest sites, countries and regions suggests that not only the total valuation of ecosystem services varies widely across studies but also the valuation of individual services. This variation suggests that policies to conserve ecosystems and their services should emphasise local contexts and values. This paper concludes by discussing the shortcomings of existing studies, and suggests that, among other things, future research should focus on the neglected ecosystem services, ‘disservices’, assess the role of dynamic factors and environmental catastrophes on the provision of ecosystem services, and assess the benefits of keeping forests intact versus converting them to alternative uses.  相似文献   

19.
Payment for ecosystem services: emerging lessons   总被引:1,自引:0,他引:1  
Market based initiatives for management of degrading ecosystems and their services have received the added attention as one of the innovative responses in the reent years. Those initiatives such as direct and indirect payment for ecosystem services like premium for rain forest honey, payment by the people at the lower reach to those at the upper reach for the watershed services etc. have drawn the attention of the decision makers as they have proved to be far more cost effective.This paper wynthesizes the key messages from some of the paper are carbon, watershed services and biodiversity, We find that while credible valuation of ecosystem services for all services remain a critical concern behind setting up the payment mechanism, absent of necessary institutional framework may seriously undermine this innovative response for management of ecosystems. In the paper, necessary institutional mechanisms enabling the market for those services have been sketched out, Key messages from those cases have been synthesized.  相似文献   

20.
Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号