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1.
生态补偿权衡关系研究进展   总被引:6,自引:3,他引:3  
徐建英  刘新新  冯琳  桓玉婷 《生态学报》2015,35(20):6901-6907
生态补偿是以市场机制解决环境外部性问题的方法,其典型特征是通过经济激励而实现生态系统保护和减贫的双赢,因此在世界范围内得到了广泛实施。权衡关系是生态补偿理论和实践中面临的问题和困境之一。生态补偿存在4种权衡关系:生态系统服务之间的权衡、监测成本与交易成本之间的权衡、公平与效率之间的权衡以及生态系统服务供应与减贫之间的权衡。分析了权衡关系的产生源于生态系统服务产生过程的不确定性、自然和社会经济系统的耦合性以及生态补偿实施背景的异质性,并提出应该在理论基础、实践模式和评估系统3个方面加强权衡关系的研究。  相似文献   

2.
Conservation policies are emerging in many places around the world, many of which involve payment for ecosystem services (PES) schemes. PES schemes provide economic incentives for forgoing land uses that reduce the provision of ecosystem services. The efficiency of such schemes depends not only on the ecosystem services provided by an area but also on the willingness of local people to forgo their land use activities. Targeting land for enrollment in PES schemes on the basis of the potential provision of ecosystem services and on the willingness to forgo certain economic activities, may therefore improve the efficiency of these schemes. The objective of this study was to develop a targeting approach, based on three surrogates derived from remotely sensed and ancillary data, for identifying land to be enrolled in one of the largest PES schemes in the world: China's Grain-to-Green Program (GTGP). The GTGP encourages farmers to return steep hillside cropland to forest by providing cash, grain and tree seedlings. The three surrogates used in the targeting approach were slope index, cropland probability, and GTGP enrollment probability. Combining these surrogates through Bernoulli trials allows targeting areas under cropland, with low opportunity costs for farmers and with potentially high soil erosion and landslide susceptibility. Results of applying the targeting approach in a case study area (Baoxing County, Sichuan Province, China) show that around half of the land currently enrolled is placed in areas with gentle slopes and tend to be located distant from forest areas. This reduces the potential benefits obtained from the GTGP. Targeting land using the proposed approach may double the benefits obtained from the program under the same budget, thus improving its efficiency. The approach may be applied to the entire GTGP implementation area in China and with proper modifications it may also be applicable to similar PES programs around the world.  相似文献   

3.
生态系统服务付费的诊断框架及案例剖析   总被引:1,自引:0,他引:1  
朱文博  王阳  李双成 《生态学报》2014,34(10):2460-2469
生态系统服务付费目前已成为生态系统服务研究的热点之一。参考Ostrom的社会-生态系统诊断框架,提取并总结影响生态系统服务付费执行效率的变量,建立了适合区域特点的项目绩效评估体系,并以哥斯达黎加(PSA)项目和中国退耕还林工程为例,探讨了该评估体系在生态系统服务付费效率诊断中的适用性。研究表明,依据该评估体系,未来中国在实施生态系统服务付费项目时应注意以下问题:建立生态系统服务付费的市场机制、实施多样化的付费方式;付费标准应考虑区域特征和供给方特征;建立生态系统服务付费项目的第三方监督和绩效评估机制;加强对生态系统服务的监测。  相似文献   

4.
In recent years, industrial ecology (IE) has become increasingly integrated into formal education as a distinct body of work. The aim of this article is to describe the state of IE in postsecondary education across the world by providing an inventory of programs and courses offered from a search conducted during the summer of 2012. Although some interpretation of the results is conducted, the aim of this article is to provide a snapshot of the state of IE in higher education in 2012 and serve as a starting point for future work. Data were collected on IE courses and programs across the world by Internet search in order to determine the prevalence of IE in postsecondary curricula. Subsequently, 190 universities and colleges from 46 countries were identified as offering courses and/or programs in IE. From this research, a total of 409 courses and 78 programs were inventoried and course content was analyzed (where available). The results indicate that IE is mainly studied at the graduate level within engineering and environmental disciplines, although undergraduate‐level curricula are emerging. In terms of disciplinary departments offering said curricula, IE is presented as a topic of instruction in varied fields of study, such as business and administration, and the arts. From the course syllabi analyzed, the main subjects being taught within IE education are introductory principles and general tools. Advanced or specialized aspects of the field are also covered, however, less frequently.  相似文献   

5.
Global conservation discourses and practices increasingly rely on market-based solutions to fulfill the dual objective of forest conservation and economic development. Although varied, these interventions are premised on the assumption that natural resources are most effectively managed and preserved while benefiting livelihoods if the market-incentives of a liberalised economy are correctly in place. By examining three nationally supported payment for ecosystem service (PES) schemes in Vietnam we show how insecure land tenure, high transaction costs and high opportunity costs can undermine the long-term benefits of PES programmes for local households and, hence, potentially threaten their livelihood viability. In many cases, the income from PES programmes does not reach the poor because of political and economic constraints. Local elite capture of PES benefits through the monopolization of access to forestland and existing state forestry management are identified as key problems. We argue that as PES schemes create a market for ecosystem services, such markets must be understood not simply as bald economic exchanges between ‘rational actors’ but rather as exchanges embedded in particular socio-political and historical contexts to support the sustainable use of forest resources and local livelihoods in Vietnam.  相似文献   

6.
Climate finance investments and international policy are driving new community-based projects incorporating payments for ecosystem services (PES) to simultaneously store carbon and generate livelihood benefits. Most community-based PES (CB-PES) research focuses on forest areas. Rangelands, which store globally significant quantities of carbon and support many of the world''s poor, have seen little CB-PES research attention, despite benefitting from several decades of community-based natural resource management (CBNRM) projects. Lessons from CBNRM suggest institutional considerations are vital in underpinning the design and implementation of successful community projects. This study uses documentary analysis to explore the institutional characteristics of three African community-based forest projects that seek to deliver carbon-storage and poverty-reduction benefits. Strong existing local institutions, clear land tenure, community control over land management decision-making and up-front, flexible payment schemes are found to be vital. Additionally, we undertake a global review of rangeland CBNRM literature and identify that alongside the lessons learned from forest projects, rangeland CB-PES project design requires specific consideration of project boundaries, benefit distribution, capacity building for community monitoring of carbon storage together with awareness-raising using decision-support tools to display the benefits of carbon-friendly land management. We highlight that institutional analyses must be undertaken alongside improved scientific studies of the carbon cycle to enable links to payment schemes, and for them to contribute to poverty alleviation in rangelands.  相似文献   

7.
Deforestation and conversion of native habitats continues to be the leading driver of biodiversity and ecosystem service loss. A number of conservation policies and programs are implemented—from protected areas to payments for ecosystem services (PES)—to deter these losses. Currently, empirical evidence on whether these approaches stop or slow land cover change is lacking, but there is increasing interest in conducting rigorous, counterfactual impact evaluations, especially for many new conservation approaches, such as PES and REDD, which emphasize additionality. In addition, several new, globally available and free high-resolution remote sensing datasets have increased the ease of carrying out an impact evaluation on land cover change outcomes. While the number of conservation evaluations utilizing ‘matching’ to construct a valid control group is increasing, the majority of these studies use simple differences in means or linear cross-sectional regression to estimate the impact of the conservation program using this matched sample, with relatively few utilizing fixed effects panel methods—an alternative estimation method that relies on temporal variation in the data. In this paper we compare the advantages and limitations of (1) matching to construct the control group combined with differences in means and cross-sectional regression, which control for observable forms of bias in program evaluation, to (2) fixed effects panel methods, which control for observable and time-invariant unobservable forms of bias, with and without matching to create the control group. We then use these four approaches to estimate forest cover outcomes for two conservation programs: a PES program in Northeastern Ecuador and strict protected areas in European Russia. In the Russia case we find statistically significant differences across estimators—due to the presence of unobservable bias—that lead to differences in conclusions about effectiveness. The Ecuador case illustrates that if time-invariant unobservables are not present, matching combined with differences in means or cross-sectional regression leads to similar estimates of program effectiveness as matching combined with fixed effects panel regression. These results highlight the importance of considering observable and unobservable forms of bias and the methodological assumptions across estimators when designing an impact evaluation of conservation programs.  相似文献   

8.
Brazil faces an enormous challenge to implement its revised Forest Code. Despite big losses for the environment, the law introduces new mechanisms to facilitate compliance and foster payment for ecosystem services (PES). The most promising of these is a market for trading forest certificates (CRAs) that allows landowners to offset their restoration obligations by paying for maintaining native vegetation elsewhere. We analyzed the economic potential for the emerging CRA market in Brazil and its implications for PES programs. Results indicate a potential market for trading 4.2 Mha of CRAs with a gross value of US$ 9.2±2.4 billion, with main regional markets forming in the states of Mato Grosso and São Paulo. This would be the largest market for trading forests in the world. Overall, the potential supply of CRAs in Brazilian states exceeds demand, creating an opportunity for additional PES programs to use the CRA market. This expanded market could provide not only monetary incentives to conserve native vegetation, but also environmental co-benefits by fostering PES programs focused on biodiversity, water conservation, and climate regulation. Effective implementation of the Forest Code will be vital to the success of this market and this hurdle brings uncertainty into the market. Long-term commitment, both within Brazil and abroad, will be essential to overcome the many challenges ahead.  相似文献   

9.
Emerging Evidence on the Effectiveness of Tropical Forest Conservation   总被引:1,自引:0,他引:1  
The PLOS ONE Collection “Measuring forest conservation effectiveness” brings together a series of studies that evaluate the effectiveness of tropical forest conservation policies and programs with the goal of measuring conservation success and associated co-benefits. This overview piece describes the geographic and methodological scope of these studies, as well as the policy instruments covered in the Collection as of June 2016. Focusing on forest cover change, we systematically compare the conservation effects estimated by the studies and discuss them in the light of previous findings in the literature. Nine studies estimated that annual conservation impacts on forest cover were below one percent, with two exceptions in Mexico and Indonesia. Differences in effect sizes are not only driven by the choice of conservation measures. One key lesson from the studies is the need to move beyond the current scientific focus of estimating average effects of undifferentiated conservation programs. The specific elements of the program design and the implementation context are equally important factors for understanding the effectiveness of conservation programs. Particularly critical will be a better understanding of the causal mechanisms through which conservation programs have impacts. To achieve this understanding we need advances in both theory and methods.  相似文献   

10.
MOTIVATION: Protein annotation is a task that describes protein X in terms of topic Y. Usually, this is constructed using information from the biomedical literature. Until now, most of literature-based protein annotation work has been done manually by human annotators. However, as the number of biomedical papers grows ever more rapidly, manual annotation becomes more difficult, and there is increasing need to automate the process. Recently, information extraction (IE) has been used to address this problem. Typically, IE requires pre-defined relations and hand-crafted IE rules or annotated corpora, and these requirements are difficult to satisfy in real-world scenarios such as in the biomedical domain. In this article, we describe an IE system that requires only sentences labelled according to their relevance or not to a given topic by domain experts. RESULTS: We applied our system to meet the annotation needs of a well-known protein family database; the results show that our IE system can annotate proteins with a set of extracted relations by learning relations and IE rules for disease, function and structure from only relevant and irrelevant sentences.  相似文献   

11.
12.
Numerous studies have used percutaneous electrical stimulation (PES) in the context of training programs to develop strength and physical performance in healthy populations (sedentary or trained). Significant increases in muscle and fiber cross-sectional area, isokinetic peak torque, maximal isometric and dynamic strength, and motor performance skills have been found after PES training. These strength gains are explained on the basis of the characteristics of PES motor units (MUs) recruitment: (a) a continuous and exhausting contractile activity in the same pool of MUs during the entire exercise period, (b) a supramaximal temporal recruitment imposed by the high frequency chosen (up to 40 Hz), and (c) a synchronous recruitment of neighboring fibers. The PES training method is complementary to voluntary training, mainly because the application of PES causes an unconventional spatial recruitment of MUs that, depending on the muscular topography, may entail the preferential recruitment of the fast-twitch MUs. In addition, the method does not specifically develop elasticity in skeletal muscle, and it must be accompanied by a technical workout.  相似文献   

13.
14.
Data on the development of theoretical basis of immunoenzyme (IE)method s (EMIT analysis and ELISA) and on using these methods in virology are presented. The problems arising in the use of most popular version of IE analysis. ELISA, are elucidated: the schemes for different variants of ELISA; the demands to adsorbent, enzyme and substrate for achieving the maximum of sensitivity of the technique; comparison of the advantages of different ELISA variants in identification of various antigens and antibodies. The data on using ELISA for indication and identification of viral antigens and virus specific antibodies are analyzed. The respiratory viruses have been used to demonstrate the possibilities of IE technique for rapid diagnostic of viral diseases and for studies in viral reproduction and structure.  相似文献   

15.
Government-funded payments for ecosystem services (PES) have increasingly been used to facilitate transactions between users of environmental services and their providers. In order to improve the link between payments and the service provided, some countries in the EU have promoted result-based schemes (RBS), which remunerate farmers for ecological results, as part of their agricultural policy. Since PES programs are voluntary, it is important to understand farmers’ responses before more large-scale implementations of RBS are initiated. Using a choice experiment and a mixed logit model, we elicited the preferences of farmers in two Natura 2000 sites in Slovenia for different design elements of a hypothetical scheme for dry grassland conservation. We found that the majority of farmers preferred the result-based approach over the management-based scheme both in terms of payment conditions and monitoring; one group of farmers preferred the RBS very strongly (average WTA of more than 500 EUR/ha/yr) and another group less strongly (average WTA about 200 EUR/ha/yr). Farmers also showed a higher preference for on-farm advise and training in small groups than for lectures, which would be offered to a larger audience. A collective bonus, which would incentivise coordination and could potentially increase participation rates in the scheme, significantly influenced the farmers’ willingness to adopt the scheme. However, the estimated average WTA was comparable or lower than the 40 EUR/ha annual bonus payment. Older farmers and those who managed small and semi-subsistent farms were significantly more likely to be highly resistant to scheme adoption no matter its design.  相似文献   

16.
Economic development and sustainable ecological and environmental development generally target different goals, and there are trade-offs and game-like behaviors between implementers and donors in reducing emissions from deforestation and degradation (REDD+) program. This paper analyzed the effects of evolutionary behaviors of REDD+ implementers and donors with respect to environmental service payments. Within a theoretical analysis framework, the evolutionary stable strategies of the implementers and donors under different contractual payments for ecosystem services (PES) scenarios are analyzed to explore contractual REDD+ payments through evolutionary game models. On this basis, anon-parametric local regression approach is used to analyze arrange of market-based contractual PES schemes in five REDD+ countries (Congo, Brazil, Ecuador, Nepal and Uganda). The results show the following: First, when the opportunity costs are less than the environmental benefits, some middle and high income developing countries are sufficiently incentivized to conserve forests, even without formal contractual PES scheme. This conservation occurs regardless of whether the industrialized countries will pay for the ecosystem services. Second, when the opportunity costs are greater than the environmental benefits, developing countries will generally not take the initiative to conserve forests when industrialized countries do not pay for the associated ecosystem services. Third, when there are enough contractual PES fines, developing countries will conserve forests, and the industrialized countries will pay for the ecosystem services. Finally, contractual PES fines are related to the costs of reducing emissions. Nepal has the largest marginal effect, and Uganda has the smallest. These results have implications for REDD+ program design and implementation: market-based contractual PES scheme should be given priority to regulate behavior of industrialized countries and developing countries in the PES scheme. Developing a targeted and differentiated contractual PES scheme requires an accounting of emission reduction costs in different countries.  相似文献   

17.
In this paper we review the data on intelligence in fra(X) males reported up to now in the literature, with special attention to its evolution with age. The available data suggest a decline in intellectual functioning in relation to age. These findings, however, should be interpreted with caution because of sampling and other methodological problems related with the fra(X) screening procedures and programs in general.  相似文献   

18.
19.
Industrial ecology (IE) is a maturing scientific discipline. The field is becoming more data and computation intensive, which requires IE researchers to develop scientific software to tackle novel research questions. We review the current state of software programming and use in our field and find challenges regarding transparency, reproducibility, reusability, and ease of collaboration. Our response to that problem is fourfold: First, we propose how existing general principles for the development of good scientific software could be implemented in IE and related fields. Second, we argue that collaborating on open source software could make IE research more productive and increase its quality, and we present guidelines for the development and distribution of such software. Third, we call for stricter requirements regarding general access to the source code used to produce research results and scientific claims published in the IE literature. Fourth, we describe a set of open source modules for standard IE modeling tasks that represent our first attempt at turning our recommendations into practice. We introduce a Python toolbox for IE that includes the life cycle assessment (LCA) framework Brightway2, the ecospold2matrix module that parses unallocated data in ecospold format, the pySUT and pymrio modules for building and analyzing multiregion input‐output models and supply and use tables, and the dynamic_stock_model class for dynamic stock modeling. Widespread use of open access software can, at the same time, increase quality, transparency, and reproducibility of IE research.  相似文献   

20.
Phosphorus in sediments — speciation and analysis   总被引:3,自引:0,他引:3  
Characterization of sediment phosphorus is commonly based on sequential chemical extractions, in which phosphorus is supposed to be selectively removed from different compounds in the sediments. The first extraction schemes were designed to quantify discrete chemical or mineralogical compounds. As extraction schemes have been tested on different sediments, several systematic errors have been detected and the schemes have been modified and simplified accordingly. Other chemical extractions or treatments have attempted to determine phosphorus bound to particles with a certain strength or binding energy, the purpose being to determine the labile, loosely bound, exchangeable, mobile or algal-available fraction of sediment phosphorus. All extraction procedures yield operationally defined fractions and cannot be used for identification of discrete phosphorus compounds. The many methodological modifications make it necessary to be cautious when comparing results from the literature in this field.  相似文献   

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