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61.
Conservation outcomes are uncertain. Agencies making decisions about what threat mitigation actions to take to save which species frequently face the dilemma of whether to invest in actions with high probability of success and guaranteed benefits or to choose projects with a greater risk of failure that might provide higher benefits if they succeed. The answer to this dilemma lies in the decision maker's aversion to risk—their unwillingness to accept uncertain outcomes. Little guidance exists on how risk preferences affect conservation investment priorities. Using a prioritization approach based on cost effectiveness, we compared 2 approaches: a conservative probability threshold approach that excludes investment in projects with a risk of management failure greater than a fixed level, and a variance‐discounting heuristic used in economics that explicitly accounts for risk tolerance and the probabilities of management success and failure. We applied both approaches to prioritizing projects for 700 of New Zealand's threatened species across 8303 management actions. Both decision makers’ risk tolerance and our choice of approach to dealing with risk preferences drove the prioritization solution (i.e., the species selected for management). Use of a probability threshold minimized uncertainty, but more expensive projects were selected than with variance discounting, which maximized expected benefits by selecting the management of species with higher extinction risk and higher conservation value. Explicitly incorporating risk preferences within the decision making process reduced the number of species expected to be safe from extinction because lower risk tolerance resulted in more species being excluded from management, but the approach allowed decision makers to choose a level of acceptable risk that fit with their ability to accommodate failure. We argue for transparency in risk tolerance and recommend that decision makers accept risk in an adaptive management framework to maximize benefits and avoid potential extinctions due to inefficient allocation of limited resources. El Efecto de la Aversión de Riesgo sobre la Priorización de Proyectos de Conservación  相似文献   
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生命周期理念,在与建筑和建设部门的关系中,特别应该进行建筑产品分析、在提高建筑物能源效率并为经济繁荣有所贡献的时候,这些产品发挥着基本的作用,已经做出的要算披露,在从自然索取的物质资源和产生的垃圾总量中,有一半来自建筑部门,为了对建筑产品的影响进行和理并把综降到最低,就必须利用生命周期的方法对所产生的影响进生检测,本文评论了生命周期理念并思考了最新的发展.材料与可持续建筑,环境产品宣言,所体现的能源以及北方与南言建筑产品评估中产生的差异,都是要讨论的话题.  相似文献   
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 Pheromone extract of the female orange wheat blossom midge, Sitodiplosis mosellana (Géhin) (SM) (Diptera: Cecidomyiidae), was analyzed by coupled gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometry (MS), employing fused silica columns coated with DB-5, DB-210, DB-23 or SP-1000. These analyses revealed a single, EAD-active candidate pheromone which was identified as 2,7-nonanediyl dibutyrate. In experiments in wheat fields in Saskatchewan, traps baited with (2S,7S)-2,7-nonanediyl dibutyrate attracted significant numbers of male SM. The presence of other stereoisomers did not adversely affect trap captures. Facile synthesis of stereoisomeric 2,7-nonanediyl dibutyrate will facilitate the development of pheromone-based monitoring or even control of SM populations. Received: 2 March 2000 / Accepted in revised form: 18 August 2000  相似文献   
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/ The rural West of the United States is considered strongly antienvironment. The traditional economic reliance of the area on natural resources has long explained this antienvironment stance. The region consistently elects federal officials who as a group consistently vote against environmental bills and seek to undo existing federal environmental regulation. These politicians defend their antienvironment actions based on their perception of the economic composition and interests of the region. Recent studies, however, have suggested that rural residents are increasingly concerned about environmental issues. These studies, however, lack a consistent theoretical basis. This article uses an alternative economic typing system to examine the economic composition of rural Idaho and suggests that the results found using the alternative typing system might provide a theoretical basis to explain why some studies are finding increased rural environmental support. The results show that rural Idaho is much more economically diverse using this alternative typing methodology compared to the outcomes of traditional USDA economic methodologies. The policy and research implications of these findings are examined.KEY WORDS: Rural; Environmental policy; Economic composition  相似文献   
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A methodology was developed to prioritize the suitability of sites for long-term monitoring of avian populations, including vulnerable species, both to enhance assessment of changes in ecological resources and to facilitate land-use planning at the regional scale. This paper argues that a successful monitoring program begins with a site prioritization procedure that integrates scores based on spatial controls with ecological and socio-economic indicators, particularly those dependent on community involvement. The evaluation strategy in this study combines 1) spatial controls such as land ownership and accessibility, with 2) biological and habitat indicators such as vulnerable species and habitat connectivity, and 3) community and agency variables such as volunteer commitment and agency priorities. In total, a set of ten indicators was identified. This strategy was applied to predominantly agricultural landscapes, which are experiencing increasing human pressures, in three sub-watersheds of the Credit River, Southern Ontario. Specifically, bird populations were recorded during the breeding seasons of 2000-2002 in nine land units or habitat types including marsh, deciduous forest, and grasslands as mapped by Credit Valley Conservation (CVC) following Ecological Land Classification (ELC) guidelines. CVC selected sites for long-term monitoring in 2002 and the relationships between the scored (or ranked) sites and the selected long-term monitoring sites are discussed.  相似文献   
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