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161.
Risk assessment/management frameworks employed around the world to guide environmental decision-making were analyzed for their approaches to developing risk management objectives and the decision criteria necessary for environmental policy implementation. Frameworks from the Netherlands, the UK, Sweden, Australia/New Zealand, Canada, and the USA were considered. Progress in refining the scientific basis for risk assessment/management has been made, but there has been little parallel development in defining the mechanisms by which available scientific information may be used to define risk management goals or identify and select between management options using a priori decision criteria. The lack of detailed guidance on the setting and achievement of risk management goals that appropriately balance technical information and public input remains an important challenge to the use and practice of all risk assessment/management frameworks. 相似文献
162.
Ecological risk management historically focused on risks to human health and the immediate human environment. Increasingly, societal interest in biodiversity and ecological integrity demands that risk assessors and managers take a broader view of the environment and include non-human species and ecosystems within their realm of concern. The greatest threats to biodiversity in the USA and much of the world are habitat alteration (including conversion, degradation, and fragmentation) and exotic species invasions. This paper reviews and integrates the results of several recent studies (e.g. by The Nature Conservancy, World Wildlife Fund, Defenders of Wildlife, and the National Biological Service) that have identified regions and ecosystems that are highly distinct biologically, are rare or declining, contain high numbers of imperiled species, face immediate threats, and stand to lose considerable biodiversity in the near future. These studies converge on a set of regions that warrant urgent attention from risk managers. Focal species and functional groups of species can be selected within these regions to characterize ecological effects and track recovery of ecosystems along the same axes (e.g. habitat structure, disturbance frequency) that led to biotic impoverishment. The most fruitful approach to risk management ultimately will be one that addresses the most urgent threats at several levels of biological organization, from focal species to communities to ecoregions. 相似文献
163.
战略环境评价及其应用初探 总被引:1,自引:0,他引:1
概述了战略环境价的概念、产生原因、研究现状及其工作程序,结合川南矿肥工程项目对它进行了应用初探,提出了计划、规划层次SEA的方法和指标,并对我国环评工作提出了建议。 相似文献
164.
重庆市近郊蔬菜基地土壤和蔬菜中重金属的质量现状 总被引:45,自引:1,他引:45
通过对重庆市近郊蔬菜基地土壤和蔬菜中重金属的监测和评价得出:重庆市近郊蔬菜基地部分土壤受到 Cd和Hg的污染;部分蔬菜受到Pb和Cd的污染。 相似文献
165.
土壤重金属污染及其修复研究 总被引:3,自引:0,他引:3
土壤重金属污染是环境和土壤科学研究者近年来研究的热点问题。在此综述了土壤重金属污染的来源及其赋存形态,介绍了各种修复方法,提出生物修复是今后重金属污染治理技术的发展方向。 相似文献
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168.
Asako Takimoto P. K. Ramachandran Nair Janaki R. R. Alavalapati 《Mitigation and Adaptation Strategies for Global Change》2008,13(7):745-761
The recognition of agroforestry as a greenhouse-gas mitigation strategy under the Kyoto Protocol to the United Nations Framework
Convention on Climate Change (UNFCCC) offers an opportunity to agroforestry practitioners to benefit from the global Carbon
(C) credit market. Our knowledge on this important topic from the semiarid regions such as the West African Sahel (WAS) is,
however, very limited. In order to fill this gap, this study was undertaken in the Ségou region of Mali (annual temperature,
29°C; annual rainfall, 300–700 mm in 60 to 90 days), focusing on two improved agroforestry systems (live fence and fodder
bank) along with traditional parkland agroforestry systems of the region. A cost–benefit analysis was conducted to assess
the economic profitability and risks associated with the systems considering them as 25-year projects and their potential
for participation in C credit market. The traditional systems had high C stock in their biomass and soil, but little potential
for sequestering additional C; on the other hand, the improved systems had low C stock, but high sequestration potential.
For the standard size live fence (291 m) and fodder bank (0.25 ha) projects, the estimated net present values (NPV) were $
96.0 and $158.8 without C credit sale, and $109.9 and $179.3 with C sale, respectively. From the C sale perspective, live
fence seemed less risky and more profitable than fodder bank. Carbon credit sale is likely to contribute to economic development
of the subsistence farmers in the WAS.
相似文献
Asako TakimotoEmail: |
169.
阐明了绿色食品的内涵,产生的历史背景、客观原因,以及发展绿色食品对保障食品安全性、解决农产品国际贸易壁垒,实现农业可续发展的重大意义。在回顾齐齐哈尔绿色食品产生发展历程,目前取得的成效及存在的主要问题基础上,提出了加快齐齐哈尔绿色食品产生发展的思路与对策,着重强调要注重保护和发送生态环境,加强生产为基地建设,建设为龙头企业、加强市场开拓等关键性问题。 相似文献
170.