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281.
That at least some aspects of nature possess intrinsic value is considered by some an axiom of conservation. Others consider nature's intrinsic value superfluous or anathema. This range of views among mainstream conservation professionals potentially threatens the foundation of conservation. One challenge in resolving this disparity is that disparaging portrayals of nature's intrinsic value appear rooted in misconceptions and unfounded presumptions about what it means to acknowledge nature's intrinsic value. That acknowledgment has been characterized as vacuous, misanthropic, of little practical consequence to conservation, adequately accommodated by economic valuation, and not widely accepted in society. We reviewed the philosophical basis for nature's intrinsic value and the implications for acknowledging that value. Our analysis is rooted to the notion that when something possesses intrinsic value it deserves to be treated with respect for what it is, with concern for its welfare or in a just manner. From this basis, one can only conclude that nature's intrinsic value is not a vacuous concept or adequately accommodated by economic valuation. Acknowledging nature's intrinsic value is not misanthropic because concern for nature's welfare (aside from its influence on human welfare) does not in any way preclude also being concerned for human welfare. The practical import of acknowledging nature's intrinsic value rises from recognizing all the objects of conservation concern (e.g., many endangered species) that offer little benefit to human welfare. Sociological and cultural evidence indicates the belief that at least some elements of nature possess intrinsic value is widespread in society. Our reasoning suggests the appropriateness of rejecting the assertion that nature's intrinsic value is anathema to conservation and accepting its role as an axiom. Evaluar si el Valor Intrínseco de la Naturaleza es un Axioma o un Anatema para la Conservación  相似文献   
282.
Abstract

In this paper, we introduce the combining stated preference and revealed preference methods which is the state-ofthe- art method for the valuation of non-market goods. Revealed preference methods and stated preference (SP) methods have both been applied by economists in valuing non-market goods; however both methods have inherent weaknesses. In order to exploit the strengths of the various approaches while minimizing their weaknesses, combining the two methods has become an important methodological option. Up to now, a growing number of literatures of studying combing the two types of data have evolved, and researchers developed three types of models to estimate combining revealed preference and stated preference data in academic fields: discrete choice model, continuous choice model and mixed choice model. Combining stated and revealed preference methods have been developed fast especially in the transport study field in which ideas could also be leant for environmental economic studies.  相似文献   
283.
兰州黄河风情线旅游资源非使用价值评价及影响因素分析   总被引:1,自引:0,他引:1  
赵勇 《资源开发与市场》2007,23(12):1139-1142
以非市场物品和服务价值评估的方法——条件价值评估法(CVM)为依据,设计并调查了游客对保护兰州市黄河风情线旅游资源的支付意愿(WTP),估算出2005年黄河风情线旅游资源非使用价值为1.52亿元,其中存在价值、遗产价值和选择价值分别为0.73亿元、0.50亿元和0.29亿元,这为黄河风情线旅游资源的保护和永续存在提供了有效的理论借鉴。  相似文献   
284.
人工湿地生态系统服务价值评价研究   总被引:3,自引:1,他引:3  
阐述了人工湿地生态系统服务的定义、分类、项目及其评价方法。介绍了生态系统服务价值评价在国内外的研究现状,指出了当前研究工作的局限性,对将来的发展方向作出了研究展望。论述了人工湿地所具有的服务功能,结合前人的研究初步提出对其进行价值评价的方法及计算公式。  相似文献   
285.
A binary response estimation procedure using contingent valuation data is proposed for estimating the incremental environmental benefits associated with the use of constructed wetlands to control agricultural waste-water runoff. The model uses two binary responses per individual while circumventing the non-independence problems associated with follow-up valuation questions. Case study results suggest that the methodology provides a potentially effective means for measuring the non-market benefits of constructed wetlands in addition to water-quality maintenance.1998 Academic Press  相似文献   
286.
Models of carbon storage in softwood and hardwood trees and forest soils and its emission from timber products and waste are developed and integrated with data on storage benefits to yield estimates of the value of the net carbon flux generated by afforestation. The long-term nature of the processes under consideration and the impact of varying the discount rate are explicitly incorporated within the model. A geographical information system (GIS) is used to apply carbon sequestration models to data on tree growth and soil type distribution for a large study area (the entire country of Wales). The major findings are: (1) all three elements under analysis (carbon sequestration in livewood, release from different products and waste, and storage or emission from soils) play a vital role in determining overall carbon flux; (2) woodland management has a substantial impact upon carbon storage in livewood however the choice of discount rate exerts the largest overall influence upon estimated carbon flux values; (3) timber growth rates (yield class) also have a major impact upon values; (4) tree species does affect storage values, however this is less important than the other factors listed above; (5) non-peat soils generally sequester relatively low levels of carbon. Planting upon peat soils can result in very substantial emissions of carbon which exceed the level of storage in livewood.The GIS is used to produce valuation maps which can be readily incorporated within cost-benefit analyses regarding optimal locations for conversion of land into forestry.  相似文献   
287.
在分析生物多样性经济价值类型的基础上探讨了自然保护区生物多样性经济价值的类型和内涵,并将其分为直接实物价值、直接非实物服务价值、生态功能间接价值和非使用类价值(包括存在价值、遗产价值和选择价值),进而提出评估这些价值的方法。  相似文献   
288.
农村生活垃圾的集中化、科学化处理对改善农村居民生活环境和农业生产环境具有重要意义。而农户对农村生活垃圾处理的支付意愿对农村生活环境的改善具有关键性作用。采用条件价值评估法(CVM)分析了三峡库区农户对处理生活垃圾的支付意愿及其影响因素。结果表明:(1)农户对农村生活垃圾处理的平均支付意愿为48元/a;(2)户主年龄、文化程度以及对环境是否关心对当地农户处理生活垃圾的支付意愿有极显著影响。户主年龄和文化程度对生活垃圾处理的支付意愿的影响为正,说明农户年龄越大、文化程度越高,对生活垃圾处理的支付意愿就越强烈。农户对环境的关心程度为正,表示农户越关心环境,对生活垃圾处理的支付意愿就越强烈。最后,提出相关建议:制定政策时要充分考虑农户的个体特征和自身利益;加强教育,提高农户的文化水平;加强环境保护宣传,提高农户的环境认知和环保意识。  相似文献   
289.
Conservation of groundwater resources is critical for maintaining the future productivity of irrigated land in the Ogallala Aquifer Region and beyond. This research explores motivations and behavior related to groundwater conservation among agricultural producers in the Colorado portion of the Republican River Basin, which is part of the Ogallala Aquifer. The empirical modeling uses data from a recently conducted survey to analyze how a common set of producer, farm, and resource characteristics influence groundwater values, concern for future groundwater availability, private conservation actions, and support for coordinated conservation efforts. We find two factors, producer age and land owner status, are consistently correlated with the key conservation‐related outcomes we evaluate. More generally, the results suggest considerable similarities in the characteristics that drive private conservation actions and support for coordinated conservation. This knowledge could be used to better target and incentivize future groundwater conservation efforts in the region. Editor's note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series.  相似文献   
290.
在对国内外森林绿色核算中林地林木估价方法综述的基础上指出:林地林木估价起源于森林评价学,已有200多年的历史,且估价方法较多,概括起来主要包括比较方式估价方法、成本方式估价方法、收益方式估价方法和收益比较折衷方式估价方法。幼、中龄林一般采用成本方式估价方法;近熟林、成熟林和过熟林采用收益方式估价方法。联合国等在综合环境经济核算体系中推荐的林地林木估价方法主要为立木价值法、消费价值法和净现值法,虽然与森林评价学上的名称不一致,但属于收益方式的评价方法。文章还分别采用成本法和净现值法对海南省、大兴安岭的林地林木进行了估价,通过估价结果的比较分析认为,成本法可作为林木估价的最低值,净现值法的估价高于成本法的估价,净现值法估价是成本价法估价的1.03~1.14倍。另外,虽然联合国等推荐的林地林木估价首选方法为净现值法,但实际计算需要大量的数据,且无论是立木价值法,还是消费价值法和净现值法估价,其结果差异很大。德国、澳大利亚和法国的研究表明,3种方法的估价结果相差2倍多。欧盟也因此推荐立木价值法估价。文章最后认为,林地林木估价的方法目前还没有达成一致,且不同的估价方法估算的结果也存在明显的差异。  相似文献   
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