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21.
This study estimates minimum marginal health benefits (morbidity reduction only) of air pollution control and total health benefits arising from regulatory intervention regarding the adoption of the World Bank emission guidelines (WBEG) for thermal power plants (TPPs) in Delhi. The Industrial Source Complex-Short-Term Version–3 (ISCST3) model has been used to estimate the contribution to air pollution from TPPs. The household health production function (avertive behaviour) has been used to value health benefits of air pollution control. The study revealed that the ambient air pollution due to TPPs is reduced by between 62.17% to 83.45% by adopting the WBEG. Annual marginal benefit due to reduction in exposure to air pollution by 1 μg m?3 is estimated to be US$0.353 per person. Total annual health benefits for adopting the WBEG for TPPs are estimated at US$235.19 million. This study provides a novel methodology to evaluate health benefits of regulatory intervention.  相似文献   
22.
This paper presents a cost-benefit analysis (CBA) of a trade-off between salmon and hydropower production in the Ume/Vindel River, northern Sweden. A distinctive element of this analysis is that estimated changes in resource conditions are based on detailed river-specific data. A salmon population model was used to develop the scenario and a novel willingness to pay (WTP) question, which caters for uncertainty in a different manner, provided an interval estimate. Non-use values are the major contributors to the benefit (96–517 millions of Swedish kronor (MSEK)) of increasing the stock of wild salmon. Sensitivity analysis suggests that the opportunity costs in terms of lost electricity are typically higher than the estimated benefits.  相似文献   
23.
To explore whether and why people sometimes reject environmental policies that improve individual and collective outcomes, we create an experimental market in which transactions generate a negative externality. Market participants endogenously determine whether to implement corrective policies. We consider three policy instruments (Pigouvian taxes and subsidies, and quantity regulation) and two levels of policy efficiency (full and half). We then explore how individual cultural worldviews might contribute to the rejection of policies that correct the market failure. Our results indicate that people often oppose policies that improve their material outcomes, and we find that such opposition is significantly explained by cultural worldviews. Interesting connections emerge between individual worldviews and specific policy instruments.  相似文献   
24.
The incorporation of economic thinking into the valuation of landscapes is still relatively new. It is an approach that yields valuable new insights and can help with prioritizing the use of scarce resources to improve and/or preserve landscapes. This paper explores and discusses the uses and limitations of economic valuation of landscapes from market failure, policy process, and theoretical and philosophical perspectives.  相似文献   
25.
Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite‐inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid‐20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host‐density threshold and cost‐benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host–parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of an uncertain environmental future.  相似文献   
26.
ABSTRACT: Presence of a river in an urban setting may contribute positively to an aesthetically pleasing environment. Such aesthetic effects are not typically linked to specific economic activities and occur, for example, when residents are exposed to a river-view. Qualities enhancing the aesthetic value of the river include the presence of parks, trails, and vegetation along the riverbanks. The value of aesthetic amenities provided by the South Saskatchewan to the City of Saskatoon residents was estimated in this study using non-market methods. The implicit price of the river view was estimated using the Hedonic Price Model, whereas value through willingness to pay for property taxes or higher rents were also estimated using actual market data. The total annual value of the river to the City of Saskatoon through addition of aesthetic amenities was estimated at $1.2 million in 1989 dollars.  相似文献   
27.
It has been argued that respondents in contingent valuation (CV) surveys, asked to value complex environmental amenities, will state willingness to pay (WTP) independently of the scope of the project. Such insensitivity to scope would be at odds with rational choice, and could therefore imply that CV is not a theoretically valid method for biodiversity valuation. The scope test in the present CV study was applied to endangered species preservation. Respondents were split in four sub-samples facing different scopes of endangered species preservation. The design allowed for both external and internal scope tests. Furthermore, the tests were split according to elicitation format. Of four external tests of insensitivity to scope, one was rejected, two gave mixed results, depending on either the type of test or elicitation format, and for the last one the null hypothesis could not be rejected. Of five internal tests, insensitivity to scope was rejected in three cases, one test gave mixed results, and one could not be rejected. Survey design features of the CV study, especially an unfamiliar sub-group of endangered species, could explain the apparent insensitivity to scope observed.  相似文献   
28.
区域洪涝灾害风险的模糊综合评价与预测   总被引:1,自引:0,他引:1  
刘合香  徐庆娟 《灾害学》2007,22(4):38-42
以广西1992~2006年洪涝灾情数据为基础,选取适当的评价指标,用基于遗传算法、特征值法和优化算法的投影寻踪法和层次分析法确定各评价指标的分类权重和排序权重,用优化算法进行综合得到组合权重,经过加权求和得出洪涝灾害的模糊综合评价,进而对15个评价对象进行了分类排序,其分类结果很好地反映了洪涝灾情的实际情况。在以上模糊综合评价结果的基础上,利用距离贴近度进一步计算和分析各个评价指标之间的贴近度,并由择近原则确定各个评价指标之间在洪涝灾害评价中的相关程度。同时,建立了基于改进的灰色GM(1,1)的时间响应式的灾变年份预测模型。  相似文献   
29.
Abstract: Nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. Although over 40 value estimates exist, it is often difficult to compare values from different studies due to variations in study design, implementation, and modeling specifications. We conducted a stated‐preference choice experiment to estimate the value of recovering or downlisting 8 threatened and endangered marine species in the United States: loggerhead sea turtle (Caretta caretta), leatherback sea turtle (Dermochelys coriacea), North Atlantic right whale (Eubalaena glacialis), North Pacific right whale (Eubalaena japonica), upper Willamette River Chinook salmon (Oncorhynchus tshawytscha), Puget Sound Chinook salmon (Oncorhynchus tshawytscha), Hawaiian monk seals (Monachus schauinslandi), and smalltooth sawfish (Pristis pectinata). In May 2009, we surveyed a random sample of U.S. households. We collected data from 8476 households and estimated willingness to pay for recovering and downlisting the 8 species from these data. Respondents were willing to pay for recovering and downlisting threatened and endangered marine taxa. Willingness‐to‐pay values ranged from $40/household for recovering Puget Sound Chinook salmon to $73/household for recovering the North Pacific right whale. Statistical comparisons among willingness‐to‐pay values suggest that some taxa are more economically valuable than others, which suggests that the U.S. public's willingness to pay for recovery may vary by species.  相似文献   
30.
Mapping, modeling, and valuing urban ecosystem services are important for integrating the ecosystem services concept in urban planning and decision-making. However, decision-support tools able to consider multiple ecosystem services in the urban setting using complex and heterogeneous data are still in early development. Here, we use New York City (NYC) as a case study to evaluate and analyze how the value of multiple ecosystem services of urban green infrastructure shifts with shifting governance priorities. We first examined the spatial distribution of five ecosystem services – storm water absorption, carbon storage, air pollution removal, local climate regulation, and recreation – to create the first multiple ecosystem services evaluation of all green infrastructure in NYC. Then, combining an urban ecosystem services landscape approach with spatial multicriteria analysis weighting scenarios, we examine the distribution of these ecosystem services in the city. We contrast the current NYC policy preference – which is focused on heavy investment in stormwater absorption – with a valuation approach that also accounts for other ecosystem services. We find substantial differences in the spatial distribution of priority areas for green infrastructure for the valuation scenarios. Among the scenarios we examined for NYC, we find that a scenario in which only stormwater absorption is prioritized leads to the most unevenly distributed ES values. By contrast, we find least variation in ES values where stormwater absorption, local climate regulation, carbon storage, air pollution removal, and recreational potential are all weighted equally.We suggest that green infrastructure planning strategies should include all landscape components that contribute to the production of ecosystem services and consider how planning priority alternatives generate different ecosystem services values.  相似文献   
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