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971.
扩大企业对CDM的参与是提高清洁发展机制减排效果的关键因素,但是随着参与的不断扩大,可能产生价格因素、小项目开发障碍、“普遍性”等阻碍因素,将影响企业对CDM参与性的继续扩大,对减排效果的提高造成负面影响。在对企业参与和CDM环境效力相互关系探讨的基础上,本文对如何继续扩大参与、加大减排提出了发展建议。  相似文献   
972.
An improved synthesis of hydroxylated polychlorinated biphenyls (PCBs) which are structurally related to the major hydroxy PCB congeners identified in human plasma is described. The coupling of (chlorinated) aryl boronic acids with bromochloro anisoles using the standard conditions of the Suzuki coupling gave the desired hydroxylated PCB metabolites in good to excellent yields. The approach offers the advantage of high selectivity and good yields compared to conventional methods such as the Cadogan reaction and allows the use of less toxic starting materials.  相似文献   
973.
Summary. We investigated the hypothesis that aggregation signals produced by male webbing clothes moths (WCM), Tineola bisselliella (Hum.) (Lepidoptera: Tineidae), and close-range male attractant signals produced by females have a pheromonal basis, at least in part. Gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric analyses of bioactive methanolic extracts of male WCM disclosed three candidate pheromone components: hexadecanoic acid methyl ester (16:Ester), (Z)-9-hexadecenoic acid methyl ester (Z9—16:Ester), and octadecanoic acid methyl ester (18:Ester). In bioassay experiments in a large Plexiglas™ arena, a blend of synthetic 16:Ester plus Z9—16:Ester was attractive to male and virgin (but not mated) female WCM; the 18:Ester was inactive. GC-EAD analyses of pheromone gland extracts from female WCM revealed (E,Z)-2,13-octadecadienal (E2Z13—18:Ald) and (E,Z)-2,13-octadecadienol (E2Z13—18:OH) as candidate sex pheromone components. In arena bioassay experiments, 1—5 female equivalents of synthetic E2Z13—18:Ald (0.2 ng) and E2Z13—18:OH (0.1 ng) were more attractive to male WCM than were two virgin female WCM. We anticipate that the combination of aggregation and sex pheromones, male-produced sonic aggregation signals, and habitat-derived semiochemicals will be highly effective in attracting male and female WCM to commercial traps. Received 12 January 2001; accepted 8 June 2001.  相似文献   
974.
We analyzed whether decision‐making triggers increase accountability of adaptive‐management plans. Triggers are prenegotiated commitments in an adaptive‐management plan that specify what actions are to be taken and when on the basis of information obtained from monitoring. Triggers improve certainty that particular actions will be taken by agencies in the future. We conducted an in‐depth, qualitative review of the political and legal contexts of adaptive management and its application by U.S. federal agencies. Agencies must satisfy the judiciary that adaptive‐management plans meet substantive legal standards and comply with the U.S. National Environmental Policy Act. We examined 3 cases in which triggers were used in adaptive‐management plans: salmon (Oncorhynchus spp.) in the Columbia River, oil and gas development by the Bureau of Land Management, and a habitat conservation plan under the U.S. Endangered Species Act. In all the cases, key aspects of adaptive management, including controls and preidentified feedback loops, were not incorporated in the plans. Monitoring and triggered mitigation actions were limited in their enforceability, which was contingent on several factors, including which laws applied in each case and the degree of specificity in how triggers were written into plans. Other controversial aspects of these plans revolved around who designed, conducted, interpreted, and funded monitoring programs. Additional contentious issues were the level of precaution associated with trigger mechanisms and the definition of ecological baselines used as points of comparison. Despite these challenges, triggers can be used to increase accountability, by predefining points at which an adaptive management plan will be revisited and reevaluated, and thus improve the application of adaptive management in its complicated political and legal context. Detonadores de la Toma de Decisiones en el Manejo Adaptativo  相似文献   
975.
There are currently no widely accepted procedures for comparing the performance of global environmental assessments (GEAs) and this may be a barrier to improving their methodology. To encourage greater self-reflection within the GEA community, it is proposed to introduce consistent evaluation approaches. Two elements from current evaluation practice are reviewed here that could be particularly useful for evaluating GEAs. The first are logic models which provide a transparent visual mapping of how activities in a GEA are intended to have impacts on policies. The second are performance metrics. It is proposed that GEAs adopt two kinds of metrics: (i) A common generic set for use in all GEAs to provide a basis for comparing the performance of GEAs, and (ii) a specific set of measureable metrics for each particular GEA derived from/linked to the generic set. Although many issues arise in applying these and other elements from evaluation theory and practice to GEAs, the potential benefits are greater comparability of GEA performance and new knowledge about how to improve them. This Short Communication is part of a Special Issue on solution-oriented GEAs.  相似文献   
976.
Today, fire in the Braziliancerrado(savanna) is predominantly caused by farmers. They use fire during the dry season to promote fresh grass regrowth in pastures for their cattle and to clear areas of planting ready for cultivation in the wet season. This study researched fire use by farmers in thecerradoof the Distrito Federal, central Brazil, in order to investigate what influences their fire management decision-making. The results show that the two main factors limiting the choice of feasible options for farmers to meet their objectives are income and time. However, perceptions also play a major role in the decision-making process, and for many farmers this alone determines whether fire is used. Various fire practices involved with timing, frequency and size, as well as precautions taken before and during the burn, and the factors influencing these decisions are presented. This study shows that it is vital to understand factors determining fire use if effective fire management plans and policies are to be developed.1998 Academic Press  相似文献   
977.
基于参与式社区评估法的泾河流域景观管理问题分析   总被引:3,自引:0,他引:3  
参与式社区评估法既兼顾了景观管理中的地理变量,同时还将社会经济因素纳入了考虑范畴,是深入进行问题分析客观有效的方法之一。本文采用参与式社区评估法,运用问题矩阵和问题树分析,对泾河流域景观管理中存在的问题和利益相关者的认知进行了分析。研究发现,绝大多数利益相关者认为土壤侵蚀已成为第一严重的问题,其次是土地生产力低下、自然灾害、植被破坏等。尽管当地公众已经认识到了土壤侵蚀的严重危害,但在安排土地利用方式时,却很少考虑土壤侵蚀带来的危害,仍然从事着自给自足的粮食生产活动。  相似文献   
978.
Environmental planning at different levels has been called for by environmental departments in China during last years to integrate environment consideration to economic development. Based on the accomplished environmental planning practice in Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps, at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental management and the decision-making. The experience shows that the ecological function zoning methods should be applied according to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders. Problems to be resolved in the future are also pointed out in the ending part.  相似文献   
979.
The nexus between human rights and the environment is a key issue for climate policymakers and Indigenous peoples around the world. We combine national spatial, social and biological datasets from Australia to describe where Indigenous carbon projects are happening, why Indigenous people are participating, and how effective these schemes might be at marrying Indigenous co-benefit, biodiversity and carbon emission mitigation goals. Our study shows that many Indigenous people engage in carbon offset schemes as part of their broader cultural responsibility for landscapes, and that they seek to grow the relationship between social and ecological benefits. It also highlights the challenges associated with designing carbon offset schemes that address the impacts of climate change and respond to Indigenous peoples’ world views about what is required to sustain cultural-social-ecological systems.  相似文献   
980.
For addressing climate change, public support for changes in policy is needed, as well changes in individual lifestyles. Both of these appear to be intimately related with people’s worldviews. Understanding these worldviews is therefore essential. In order to research and ‘map’ them, we translated the theoretical ‘Integrative Worldview Framework’ (IWF) into an empirical, quantitative approach. We constructed a worldview-scale aiming to distinguish between four major worldviews – labeled traditional, modern, postmodern, and integrative – and explored their interface with opinions and behaviors with respect to climate change. The survey was conducted with representative samples of citizens in the Netherlands and the USA (n = 527 and n = 556). The hypothesized worldviews were found in the data with a reasonable degree of reliability, especially in the Dutch sample. We also found consistent relationships between these worldview-clusters and a range of opinions, political priorities, and behaviors. In both countries postmoderns and integratives displayed significantly more concern about climate change as well as more sustainable behaviors, compared with moderns and traditionals. The implications of these findings for environmental policy and social science are noteworthy.  相似文献   
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