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461.
The high seas provide a variety of ecosystem services that benefit society. There have, however, been few attempts to quantify the human welfare impacts of changes to the delivery of these benefits. We assessed the values of several key ecosystem service benefits derived from protecting ecosystems in the high seas of the Flemish Cap through choice experiments conducted in Canada, Norway, and Scotland. Rather than solely eliciting public willingness to pay, we also explored the determinants of variance in the estimates of willingness to pay. We aimed to determine how much respondents were willing to pay for high-seas ecosystems conservation, which factors influence individuals’ willingness to pay, and whether individuals in Canada had a higher willingness to pay relative to those living in Norway and Scotland. This latter point captures distance-decay effects. On average, the public placed positive value on conserving high-seas ecosystems and on developing economic activities related to the exploitation and exploration of marine resources, despite a lack of awareness and familiarity with these environments. Distance-decay effects on willingness to pay were not clear. Scots had the highest willingness to pay and the Norwegians the lowest willingness to pay for all attributes, with the only exception being willingness to pay for a large increase in new jobs, in which case Canadians’ willingness to pay was higher than Scots’. The public's willingness to pay was influenced by sociodemographic characteristics and their perceptions of high-seas ecosystems. Our results provide evidence of the impacts of high-seas governance on human welfare and that improved governance could increase the value people place on high-seas ecosystems and the services they produce.  相似文献   
462.
Abstract: The economic valuation of ecosystem services is a key policy tool in stemming losses of biological diversity. It is proposed that the loss of ecosystem function and the biological resources within ecosystems is due in part to the failure of markets to recognize the benefits humans derive from ecosystems. Placing monetary values on ecosystem services is often suggested as a necessary step in correcting such market failures. We consider the effects of valuing different types of ecosystem services within an economic framework. We argue that provisioning and regulating ecosystem services are generally produced and consumed in ways that make them amenable to economic valuation. The values associated with cultural ecosystem services lie outside the domain of economic valuation, but their worth may be expressed through noneconomic, deliberative forms of valuation. We argue that supporting ecosystem services are not of direct value and that the losses of such services can be expressed in terms of the effects of their loss on the risk to the provision of the directly valued ecosystem services they support. We propose a heuristic framework that considers the relations between ecological risks and returns in the provision of ecosystem services. The proposed ecosystem‐service valuation framework, which allows the expression of the value of all types of ecosystem services, calls for a shift from static, purely monetary valuation toward the consideration of trade‐offs between the current flow of benefits from ecosystems and the ability of those ecosystems to provide future flows.  相似文献   
463.
Cochran, Bobby and Charles Logue, 2011. A Watershed Approach to Improve Water Quality: Case Study of Clean Water Services’ Tualatin River Program. Journal of the American Water Resources Association (JAWRA) 47(1):29‐38. DOI: 10.1111/j.1752‐1688.2010.00491.x Abstract: Over the last five years, Clean Water Services developed and implemented a program to offset thermal load discharged from its wastewater facilities to the Tualatin River by planting trees to shade streams and augmenting summertime instream flows. The program has overcome challenges facing many of the nation’s water quality trading programs to not only gain consensus on the frameworks needed to authorize trading, but also provide a broad range of ecosystem services. This paper compares the Tualatin case study with some of the commonly cited factors of successful trading programs.  相似文献   
464.
生态系统服务价值损失评估是流域突发水污染事件生态损害定量、污染事故责任认定的重要依据.针对流域突发污染事件损失定量问题,基于生态系统服务价值理论,构建了包含不同主导服务偏好的生态系统服务价值损失指标评估方法,提出了受损服务识别、评估指标筛选、损失价值核算三步评估程序,并以浙江省某河段苯酚泄漏事件造成的流域生态系统服务损失为例进行实际测算,结合实例以1-9标度层次分析法(AHP)验证了该方法偏好系数计算方法的可靠性.结果表明,本方法与AHP法的水体生态系统服务损失评估额相对偏差为2.5%,单项指标损失额排序相同,并且在保证评估结果可靠性的前提下更具易操作性优势.  相似文献   
465.
贵州省威宁草海是贵州最大的天然高原淡水湖泊,同时也是我国亚热带高原湿地生态系统的典型代表,成为中国西南地区迁徙水禽的重要越冬地和停歇地。但草海湿地生态系统由于人类活动加剧引起的其功能作用会削弱、生物多样性会降低、水体富营养化等生态环境问题多方面的影响导致其表现出明显的生态脆弱性,尤其是在其生态系统的生态环境方面表现尤为突出。如果草海受到多方面的影响不及时加以制止和消除,将直接威胁着草海湿地生态系统的稳定。本文首先从湿地的生态特征、功能和社会经济环境三个方面的30个主要影响草海生态健康的因子进行分析,并对每个因子的健康状况进行调查、分析说明。其次,利用模糊综合评价模型中的层次分析法对草海生态健康影响的30个主要因子进行了整合分析,并对草海现在的健康状况应用平均加权原则进行了评估。最后,针对草海目前的健康状况,对草海今后的防治提出了相关建议。  相似文献   
466.
通过剖析传统的敏感性分析法,提出交叉敏感性概念,评价生态服务价值对土地利用类型转换的响应性。以克里雅绿洲为研究区域,以1991、2002 和2011 年三期遥感影像数据为基本信息源,运用交叉敏感性分析,计算生态系统服务价值对土地利用类型转换的敏感性,确定生态系统日趋敏感的土地利用变化过程,为土地管理对策提供参考依据。研究结果表明:20 a来,克里雅绿洲生态服务价值较敏感的土地利用转换类型相对稳定,主要集中在湿地和水体向荒漠和低覆盖度草地的转换;与1991 和2011 年相比,2002 年的交叉敏感性系数普遍上升,这主要是因为湿地、水体面积的减少加剧了研究区的生态脆弱性,从而表现出更大的敏感性;湿地和水体向耕地转换的交叉敏感性一直处于上升趋势,并不断接近于-1,表明生态服务价值对高强度的人为活动变得越来越敏感,从而警示地方管理部门采取必要措施制止此种转换的持续。  相似文献   
467.
Abstract: Conservation prioritization usually focuses on conservation of rare species or biodiversity, rather than ecological processes. This is partially due to a lack of informative indicators of ecosystem function. Biological soil crusts (BSCs) trap and retain soil and water resources in arid ecosystems and function as major carbon and nitrogen fixers; thus, they may be informative indicators of ecosystem function. We created spatial models of multiple indicators of the diversity and function of BSCs (species richness, evenness, functional diversity, functional redundancy, number of rare species, number of habitat specialists, nitrogen and carbon fixation indices, soil stabilization, and surface roughening) for the 800,000‐ha Grand Staircase‐Escalante National Monument (Utah, U.S.A.). We then combined the indicators into a single BSC function map and a single BSC biodiversity map (2 alternative types of conservation value) with an unweighted averaging procedure and a weighted procedure derived from validations performance. We also modeled potential degradation with data from a rangeland assessment survey. To determine which areas on the landscape were the highest conservation priorities, we overlaid the function‐ and diversity‐based conservation‐value layers on the potential degradation layer. Different methods for ascribing conservation‐value and conservation‐priority layers all yielded strikingly similar results (r= 0.89–0.99), which suggests that in this case biodiversity and function can be conserved simultaneously. We believe BSCs can be used as indicators of ecosystem function in concert with other indicators (such as plant‐community properties) and that such information can be used to prioritize conservation effort in drylands.  相似文献   
468.
Extensive green areas generate a recognizable green identity of Ljubljana. Due to the challenges of climate change and urbanization the city's spatial policy highlights revitalization of degraded urban areas, preserving the quality and scope of the existing green network and the protection of multifunctional natural areas surrounding the city. Article describes the project of Rakova Jelša Park as a good example of these policies. With an NGO initiative a former degraded area with illegal dumping and non-indigenous vegetation was transformed into recreational park with increased biocultural diversity. Important lesson of the project is that opening up space for public use not only prevents degradation, but also improves the quality of urban ecosystems. One of the challenges for the city's future sustainable ecosystem development will be a more active cooperation with its citizens in the green infrastructure policy and later also a partial transfer of responsibility for green areas to them.  相似文献   
469.
Ecosystem approach, a new comprehensive approach to the conservation and management of natural resources, has received universal concern and approval in the world, and it requires the application of the eco-compensation mechanism. Some basic ideas for establishing the marine eco-compensation mechanism are: payers and payees can be identified through analyzing marine ecosystem service changes and impacts on the stakeholders; financial transfer payment and environmental taxes and fees can be used as the main channels for compensation; payment standard can be set up by following the principle of a compromise between calculated theoretic results and “price bargaining”. Focusing on the key human impact on marine ecosystem in Bohai Sea, some preliminary ides on eco-compensation application are given: reform the ongoing charge system of pollutant discharge and enhance its incentives to reduce land pollutants; implement eco-compensation for freshwater demand between Bohai Sea and the river basins for the purpose of increasing freshwater inflow; popularize and strengthen the existing eco-compensation on fishery resources management, and implement the charge system of eco-compensation on reclamation from the sea for land construction.  相似文献   
470.
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