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521.
High alpine peaks throughout the world are under increasing environmental pressure from hikers, trekkers, and climbers. Colorado's “Fourteeners”, peaks with summits above 14,000 feet are no exception. Most of these peaks have no entrance fees, and reach ecological and social carrying capacity on weekends. This paper illustrates how a series of dichotomous choice contingent valuation questions can be used to evaluate substitutability between different alpine peaks and quantify the price responsiveness to an entrance fee. Using this approach, we find that peak load pricing would decrease use of popular Fourteeners in Colorado by 22%. This reduction is due almost entirely to substitution, rather than income effects. There is also price inelastic demand, as 60% of the hikers find no substitution for their specific Fourteener at the varying cost increases posed in the survey. The no substitute group has a mean net benefit of $294 per hiker, per trip, considerably higher than visitor net benefits in most recreational use studies.  相似文献   
522.
Burning municipal solid waste (MSW) can generate energy and reduce the waste volume, which delivers benefits to society through resources conservation. But current practices by society are not sustainable because the associated environmental impacts of waste incineration on urbanized regions have been a long-standing concern in local communities. Public reluctance with regard to accepting the incinerators as typical utilities often results in an intensive debate concerning how much welfare is lost for those residents living in the vicinity of those incinerators. As the measure of welfare change with respect to environmental quality constraints nearby these incinerators remains critical, new arguments related to how to allocate the fair fund among affected communities became a focal point in environmental management. Given the fact that most County fair fund rules allow a great deal of flexibility for redistribution, little is known about what type of methodology may be a good fit to determine the distribution of such a fair fund under uncertainty. This paper purports to demonstrate a system-based approach that helps any fair fund distribution, which is made with respect to residents' possible claim for fair damages due to the installation of a new incinerator. Holding a case study using integrated geographic information system (GIS) and fuzzy analytic hierarchy process (FAHP) for finding out the most appropriate distribution strategy between two neighboring towns in Taipei County, Taiwan demonstrates the application potential. Participants in determining the use of a fair fund also follow a highly democratic procedure where all stakeholders involved eventually express a high level of satisfaction with the results facilitating the final decision making process. It ensures that plans for the distribution of such a fair fund were carefully thought out and justified with a multi-faceted nature that covers political, socio-economic, technical, environmental, public health, and industrial aspects.  相似文献   
523.
Water demands in the Aegean Islands have increased steadily over the last decade as a result of a building boom for new homes, hotels, and resorts. The increase in water demand has resulted in the disruption of past sustainable water management practices. At present, most freshwater needs are met through the use of the limited groundwater, desalinated seawater, and freshwater importation. Wastewater reclamation, not used extensively, can serve as an alternative source of water, for a variety of applications now served with desalinated and imported water. Three alternative processes: desalination, importation, and water reclamation are compared with respect to cost, energy requirements and long-term sustainability. Based on the comparisons made, water reclamation and reuse should be components of any long-term water resources management strategy.  相似文献   
524.
The valuation of historical sites: a case study of Valdivia,Chile   总被引:1,自引:0,他引:1  
The economic valuation of cultural heritage is an area of increasing interest and an important research topic in the emerging field of cultural economics. Many services and values associated with cultural heritage are not traded in markets, and their estimation requires methods developed for the valuation of non-market goods, such as those used in environmental economics. This paper applies the contingent valuation method with double dichotomous choice to estimate the value of historical sites in the city of Valdivia, Chile. The valuation exercise was implemented by designing a hypothetical guided walking tour to a cluster of historical sites in the city centre, and surveying tourists visiting the city during the summer of 2004. Parametric and non-parametric statistical methods were used to estimate the survival distribution and the mean and median estimates of the willingness-to-pay (WTP). The study emphasizes the importance of explicitly treating heterogeneous preferences and the sensitivity of the survival distribution to the estimation methods used.  相似文献   
525.
Abstract: Recent national concerns regarding the environmental occurrence of emerging contaminants (ECs) have catalyzed a series of recent studies. Many ECs are released into the environment through discharges from wastewater treatment plants (WWTPs) and other sources. In 2005, the U.S. Geological Survey and the City of Longmont initiated an investigation of selected ECs in a 13.8‐km reach of St. Vrain Creek, Colorado. Seven sites were sampled for ECs following a Lagrangian design; sites were located upstream, downstream, and in the outfall of the Longmont WWTP, and at the mouths of two tributaries, Left Hand Creek and Boulder Creek (which is influenced by multiple WWTP outfalls). Samples for 61 ECs in 16 chemical use categories were analyzed and 36 were detected in one or more samples. Of these, 16 have known or suspected endocrine‐disrupting potential. At and downstream from the WWTP outfall, detergent metabolites, fire retardants, and steroids were detected at the highest concentrations, which commonly exceeded 1 μg/l in 2005 and 2 μg/l in 2006. Most individual ECs were measured at concentrations less than 2 μg/l. The results indicate that outfalls from WWTPs are the largest but may not be the sole source of ECs in St. Vrain Creek. In 2005, high discharge was associated with fewer EC detections, lower total EC concentrations, and smaller EC loads in St. Vrain Creek and its tributaries as compared with 2006. EC behavior differed by individual compound, and some differences between sites could be attributed to analytical variability or to other factors such as physical or chemical characteristics or distance from contributing sources. Loads of some ECs, such as diethoxynonylphenol, accumulated or attenuated depending on location, discharge, and distance downstream from the WWTP, whereas others, such as bisphenol A, were largely conservative. The extent to which ECs in St. Vrain Creek affect native fish species and macroinvertebrate communities is unknown, but recent studies have shown that fish respond to very low concentrations of ECs, and further study on the fate and transport of these contaminants in the aquatic environment is warranted.  相似文献   
526.
Thompson, Christopher L., Raymond J. Supalla, Derrel L. Martin, and Brian P. McMullen, 2009. Evidence Supporting Cap and Trade as a Groundwater Policy Option for Reducing Irrigation Consumptive Use. Journal of the American Water Resources Association (JAWRA) 45(6):1508‐1518. Abstract: In the American West water is becoming an increasingly scarce resource. Obligations to bordering states, endangered species protection, and long‐term resource sustainability objectives have created a need for most western states to reduce the consumption of irrigation water. In Nebraska specifically, the Nebraska Department of Natural Resources (NDNR) and local Natural Resource Districts (NRDs) are meeting a large part of this need by using a regulatory approach, commonly called groundwater allocation. The cost of allocation, which occurs in the form of reduced economic returns to irrigation, could be greatly reduced by using an integrated cap and trade approach. Much like environmental cap and trade programs which are used to reduce the cost of limiting environmental pollution, the trading of capped groundwater allocations can reduce the cost of limiting water use. In an analysis of a typical case in the Nebraska Republican Basin, we found that the impact of a water market to trade groundwater allocations depended on the size of the allocation and on the characteristics of the land and irrigation systems involved in the trade. Potential economic benefits from trade ranged from US$0 to US$120 per 1,000 cubic meters traded, from US$25 to US$250 per 1,000 cubic meters of reduction in consumptive use, and from US$16 to US$50 per hectare of irrigated land in the region. The highest benefits occurred at relatively high allocations, which capped withdrawals at 65‐75% of the expected unrestricted pumping level. These gains from trade would be split between buyers and sellers based on the negotiated selling price.  相似文献   
527.
基于AHP的校园安全评价指标研究   总被引:3,自引:0,他引:3  
通过对校园安全隐患的调查和分析,提出应用层次分析法和模糊综合评价所构建的AHP模型对校园安全进行评价,并结合实例给出了应用模型进行评价的步骤和方法。评价结果表明,建立的校园安全评价体系科学、合理、简单易行,具有可行性和指导性。  相似文献   
528.
生计资本与生计策略关系研究——以张掖市甘州区为例   总被引:10,自引:0,他引:10  
农民的生计安全与质量问题是当今中国农村的核心问题,稳定的生计可以使有关的政策协调发展、消除贫困并可持续地利用资源.本文采用可持续生计框架为研究基础,农户的生计资产为框架核心,通过建立可持续生计评价指标体系,对农户的生计资产状况和由此决定的资产配置方式--生计策略及二者之间的关系进行初步的研究探讨.结果表明:对张掖市甘州区农户而盲,物质资本的值最高(其值为0.609),人力资本的数值相对较高(其值为0.516),社会资本次之(其值为0.354),金融资本和自然资本的数值相对较低(其值分别为0.286和0.241).在其他条件不变的情况下,自然资本每增加一个单位,将引起农户选择以非农为主与以农业为主生计策略的发生比缩小0.119倍;当其他解释变量不变时,金融资本每增加一个单位,将引起农户选择以非农为主与以农业为主生计策略的发生比扩大9.698倍.所以要想实现农户生计多样化,加强农户抵御风险的能力,政府就必须加强对其资金、技术等方面的支持,使其有能力和资本储备从农业生产转向二、三产业,从而促使农户生计水平得以提高.  相似文献   
529.
改革开放三十年来以代工贸易为主的经济增长,在创造大量国民财富的同时,也来造成了严峻的资源短缺和生态破坏.因此,中国政府把建设"资源节约"和"环境友好"的"两型"社会,提升到国家未来发展战略的高度予以重视.而建设"两型"社会的关键,在于设立合理的制度安排,以实现企业行为与社会可持续发展的目标保持一致.就传统手段而言,这种制度安排主要依赖政府所设立的生态补偿机制.但是,这一机制在实践中存在诸多问题,大有完善的空间.本文基于Hotelling模型关于企业间博弈的相关主张,从企业理性行为的角度,寻求一条不同于政府被动监管行为的路径,来实现"两型"社会的建设蓝图.模型推导认为,品牌经济的发展模式可以有效激励企业采取长期导向、追求价值差异和关注公司声誉,进而实现资源节约及环境友好的社会福利改进.并且,由于这种机制兼顾了企业的盈利动机,因而更能够在实践当中行之有效,能指导各个地区实现经济发展模式的转型与升级.  相似文献   
530.
The green economy is an emergent approach to sustainable development launched at Rio+20. Herein environmental decision-making is increasingly achieved through economistic processes and logic. The natural commons are quantified and managed as natural capital. This paper summarizes the trajectory of the project and its ideological framework. It examines various conceptualizations of economic approaches to the environment and considers philosophical, methodological, and political problems associated with the green economy project. In the face of very different definitions of what constitutes a green economy, environmental communicators face a situation characterized by discursive confusion as the complexity of natural capital accounting processes conceal new political configurations. Counter movements argue that the green economy program is performing ideological work that uses language of environmentalism to obscure an intensified agenda of neoliberal governance and capital accumulation. The concept now has contradictory meanings. Environmental communicators have an important role to play in exposing the contested nature of the project and in helping to define the emerging green economy.  相似文献   
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