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61.
Protected areas (PAs) and payments for ecosystem services (PES) are the top two mechanisms available for countries to achieve international REDD agreements, yet there are few empirical comparisons of their effects. We estimate the impacts of PAs and PES on forest conservation, poverty reduction, and population change at the locality level in Mexico in the 2000s. Both policies conserved forest, generating an approximately 20–25% reduction in expected forest cover loss. PES created statistically significant but small poverty alleviation while PAs had overall neutral impacts on livelihoods. Estimates by individual policy type for the same level of deforestation risk indicate that biosphere reserves and PES balanced conservation and livelihood goals better than strict protected areas or mixed-use areas. This suggests that both direct and incentive-based instruments can be effective, and that policies combining sustainable financing, flexible zoning, and recognition of local economic goals are more likely to achieve conservation without harming livelihoods.  相似文献   
62.
Mitigation and offset programs designed to compensate for ecosystem function losses due to development must balance losses from affected ecosystems with gains in restored ecosystems. Aggregation rules applied to ecosystem functions to assess site equivalence are based on implicit assumptions about the substitutability of functions among sites and can profoundly influence the distribution of restored ecosystem functions on the landscape. We investigated the consequences of rules applied to the aggregation of ecosystem functions for wetland offsets in the Beaverhill watershed in Alberta, Canada. We considered the fate of 3 ecosystem functions: hydrology, water purification, and biodiversity. We set up an affect‐and‐offset algorithm to simulate the effect of aggregation rules on ecosystem function for wetland offsets. Cobenefits and trade‐offs among functions and the constraints posed by the quantity and quality of restorable sites resulted in a redistribution of functions between affected and offset wetlands. Hydrology and water purification functions were positively correlated with one another and negatively correlated with biodiversity function. Weighted‐average rules did not replace functions in proportion to their weights. Rules prioritizing biodiversity function led to more monofunctional wetlands and landscapes. The minimum rule, for which the wetland score was equal to the worst performing function, promoted multifunctional wetlands and landscapes. The maximum rule, for which the wetland score was equal to the best performing function, promoted monofunctional wetlands and multifunctional landscapes. Because of implicit trade‐offs among ecosystem functions, no‐net‐loss objectives for multiple functions should be constructed within a landscape context. Based on our results, we suggest criteria for the design of aggregation rules for no net loss of ecosystem functions within a landscape context include the concepts of substitutability, cobenefits and trade‐offs, landscape constraints, heterogeneity, and the precautionary principle.  相似文献   
63.
The discount rate for cost-benefit analysis has to take account of future scarcity of ecosystem services in consumption and production. Previous literature focuses on the first aspect and shows the importance of the relative price effect, for given growth rates of consumption and ecosystem services. This paper focuses on intermediate ecosystem services in production and shows that for limited substitutability and a low growth rate of these ecosystem services, the growth rate of consumption, and thus the discount rate, declines towards a low value. Using a Ramsey growth model, the paper distinguishes three cases. If ecosystem services can be easily substituted, the discount rate converges to the usual value in the long term. Secondly, if ecosystem services can be easily substituted in production but not in consumption, the relative price effect is important. Finally, and most interestingly, if ecosystem services cannot be easily substituted in production, the discount rate declines towards a low value and the relative price effect is less important. Another part of the previous literature has shown that a declining discount rate is the result of introducing several forms of uncertainty, but this paper reaches that conclusion from an endogenous effect on the growth rate of the economy.  相似文献   
64.
ABSTRACT

Sketch-map-facilitated interviews were conducted in 23 villages in two adjacent regions in the southern Yucatan Peninsula of Mexico – the Maya (and increasingly Mennonite) forest-agriculture mosaic of the Chenes, and the late-20th-century-settlement forest frontier of Calakmul – to determine the frequency and typology of local-scale reserves, including the external (e.g. Payments for Environmental Services programs) and internal sources of their generation. 9% of the study communities are found to satisfy the author’s criteria for deliberate, autochthonous reserves. The static polygon reserve and static map are found to have limited value for understanding the evolving cultural ecologies of these regions. Alternative approaches are discussed, particularly those employed by geographers.  相似文献   
65.
Traditional water harvesting systems are multi-functional in nature and provide a variety of ecosystem services that contribute to the overall wellbeing of local people. This study aims to identify and analyze the factors influencing the variations in the level of awareness across households residing around three selected traditional water bodies in the Indian state of West Bengal. Ordinary least square (OLS) regression models have been used to identify and analyze the determinants of household perception on ecosystem services from tank water bodies. Results show that while a majority of households have strong perceptions on the provisioning and cultural ecosystem services of the tanks, the household perceptions on regulating and supporting services of the tank is found to be relatively weak. Households belonging to lower caste and poor are likely to be more dependent on ecosystem services from tanks than upper caste and rich households, and hence they have better perceptions of provisioning ecosystem services. Households’ awareness about provisioning ecosystem services is negatively related to their level of education and wealth. It is observed that household awareness about regulating and supporting ecosystem services is positively associated with the level of education of the households, ownership of tube well and private tanks. While it is essential to consider household perception on all the ecosystem services for sustainable use and management of traditional water harvesting systems, incorporating the local norms, customs and preferences in policy design are critical for achieving effective conservation outcomes.  相似文献   
66.
The ecosystem services (ES) concept is being increasingly incorporated into environmental policy formulation and management approaches. The Corporate Ecosystem Services Review (ESR) is a framework used to assess the dependence and impact that a business has on ES. The success of the corporate experience of ES assessment provides an opportunity for adaption for local authority decision making. In this paper, the ESR tool was adapted to the South African setting at a local government level, and tested at two sites in the Msunduzi Municipality, KwaZulu-Natal. In testing the tool and gathering feedback from key stakeholders, it was found that there are both opportunities and challenges to this approach. Overall, however, it provides an opportunity for the systematic inclusion of ES assessment into existing regulatory frameworks for land-use planning and Integrated Environmental Management, whether in a strategic application, at a broader spatial (municipal) scale or in a specific locale within the municipality.  相似文献   
67.
城市生态系统健康评价是城市可持续发展以及城市生态文明建设的需要。在当今各种"城市病"频发的背景下,研究城市生态系统健康水平,不仅有利于协调城市发展与城市生态系统健康之间的矛盾,而且对于指导城市建设规划编制,监控城市生态环境的可持续发展具有重要的现实意义。鉴于此,论文在原有的城市生态系统健康评价指标的基础上,通过基于混合指标值的TODIM方法评价东营市2007—2013年间的城市生态系统健康状况,并分析活力、组成结构、恢复力、维持生态系统服务功能以及生态系统认知的构成指标对城市生态系统健康状况的影响。为了避免主观判断对城市生态系统健康评价的不确定性,文章采用兼顾客观信息和主观信息的组合权重赋权法确定各个指标的权重;根据东营市城市生态系统健康评价指标的特性和数据特点,建立了混合多属性决策TODIM方法的数学模型;采用扩展的TODIM方法对东营市城市生态系统健康状况进行评价,并分析了各个指标在城市生态发展过程中的作用。研究表明:(1)东营市的城市生态系统健康状况一直向好,由脆弱状态逐渐过渡到亚健康状态,但是生态状况仍然不容乐观,距离健康状态仍有较大的差距;(2)环保投入力度不足、污染物排放量增加、产业结构仍不完善、建成区人口密度过高等成为制约东营市城市生态系统健康发展的突出问题。文章提出了相应的对策建议,以促进城市生态系统的健康发展。  相似文献   
68.
Urban futures that are more resilient and sustainable require an integrated social–ecological system approach to urban policymaking, planning, management, and governance. In this article, we introduce the Urban Biodiversity and Ecosystem Services (URBES) and the Cities and Biodiversity Outlook (CBO) Projects as new social–ecological contributions to research and practice on emerging urban resilience and ecosystem services. We provide an overview of the projects and present global urbanization trends and their effects on ecosystems and biodiversity, as a context for new knowledge generated in the URBES case-study cities, including Berlin, New York, Rotterdam, Barcelona, and Stockholm. The cities represent contrasting urbanization trends and examples of emerging science–policy linkages for improving urban landscapes for human health and well-being. In addition, we highlight 10 key messages of the global CBO assessment as a knowledge platform for urban leaders to incorporate state-of-the-art science on URBES into decision-making for sustainable and resilient urban development.  相似文献   
69.
This paper reports a choice experiment used to estimate the value of street trees in the city center of Lodz, Poland, and the broader context of how valuation results helped to improve governance of urban ecosystem services in this city. Based on a simplified inventory of trees, we prepared a set of hypothetical programs which put varying emphasis on the different ways to increase the numbers of trees, along with different levels of a hypothetical tax that would have to be paid by respondents to implement a given program. Our study indicated that the 351 surveyed Lodz residents were willing to pay the highest price for greening those streets where currently there are few or no trees and confirmed the general importance of planting trees. The results provided an argument in the debate on the new development strategy for the city and helped to promote the concept of ecosystem services.  相似文献   
70.
基于浙江省嘉兴市1979~2012年的土地利用数据,评估了各种土地利用类型的生态系统服务价值,分析了30多年来嘉兴市土地生态系统服务价值的动态变化及其对土地利用变化和景观格局变化的响应。结果表明:(1)1979~2012年,嘉兴市建设用地面积变化最大,增加了136.6%,相应的耕地面积减少了15.5%。(2)1979~2012年,嘉兴市景观破碎度指数从0.6531上升到0.8762,随着城市化进程的加剧,耕地景观破碎度指数不断增加、聚集度指数减小。(3)1979~2012年,嘉兴市的总生态系统服务价值减少了14.7%,2000~2012年嘉兴市总的生态系统服务价值减少尤为显著,生态系统各单项服务价值整体也呈现下降趋势,耕地为嘉兴市提供的生态系统服务占嘉兴市总生态系统服务的70%以上。(4)运用相关分析方法对嘉兴市土地利用类型和景观格局对土地生态系统服务价值的影响分析表明,耕地和水域与生态服务价值呈正相关,而建设用地和未利用地与生态服务价值呈负相关;景观多样性指数(SHDI)和耕地破碎度指数与生态系统服务总价值呈显著负相关关系。  相似文献   
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