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291.
Conservation planning aims to protect biodiversity by sustainng the natural physical, chemical, and biological processes within representative ecosystems. Often data to measure these components are inadequate or unavailable. The impact of human activities on ecosystem processes complicates integrity assessments and might alter ecosystem organization at multiple spatial scales. Freshwater conservation targets, such as populations and communities, are influenced by both intrinsic aquatic properties and the surrounding landscape, and locally collected data might not accurately reflect potential impacts. We suggest that changes in five major biotic drivers—energy sources, physical habitat, flow regime, water quality, and biotic interactions—might be used as surrogates to inform conservation planners of the ecological integrity of freshwater ecosystems. Threats to freshwater systems might be evaluated based on their impact to these drivers to provide an overview of potential risk to conservation targets. We developed a risk-based protocol, the Ecological Risk Index (ERI), to identify watersheds with least/most risk to conservation targets. Our protocol combines risk-based components, specifically the frequency and severity of human-induced stressors, with biotic drivers and mappable land- and water-use data to provide a summary of relative risk to watersheds. We illustrate application of our protocol with a case study of the upper Tennessee River basin, USA. Differences in risk patterns among the major drainages in the basin reflect dominant land uses, such as mining and agriculture. A principal components analysis showed that localized, moderately severe threats accounted for most of the threat composition differences among our watersheds. We also found that the relative importance of threats is sensitive to the spatial grain of the analysis. Our case study demonstrates that the ERI is useful for evaluating the frequency and severity of ecosystemwide risk, which can inform local and regional conservation planning.  相似文献   
292.
环境影响评价制度和社会稳定风险评估制度作为预防和控制环境影响、创新社会风险管理的重要制度,实施以来发挥了重要作用,但也出现了工作边界和内容范围交叉的问题。尤其是近年来,环境污染焦虑引发社会风险事件的建设项目不断增多,导致两者的"天然联系"愈发紧密,工作存在模糊地带的问题愈发凸显,致使建设项目行政审批繁复、执行力差。在梳理环评、稳评的发展历程和存在问题的基础上,深入分析了环评和稳评的法律地位、适用范围、评价目标、评价内容、实施主体和程序上的异同,剖析了两者在制度设计和内容衔接方面的关系,并从理清工作边界职责、环境社会风险评估结果共享、强化稳评公众参与等方面提出了环评和稳评政策衔接的建议,为政府有效实施建设项目环境、社会监管提供决策参考。  相似文献   
293.
关于环境影响评价几个问题的探讨   总被引:3,自引:0,他引:3  
通过对传统发展模式下的环境影响评价的分析和探讨,指出其存在的主要缺失;提出可持续发展的环境影响评价需要强化的机制和面临的新课题,对环境影响评价为当前的环境保护服务提出几点可行的建议。  相似文献   
294.
本文对如何提高环境评价质量提出了一些看法。作者指出,应使环境评价工作具有针对性、实用性和科学性,并强调做好工程分析和事故评价的重要意义。  相似文献   
295.
Guild management: an evaluation of avian guilds as a predictive tool   总被引:4,自引:0,他引:4  
The use and applicability of the guild concept to management is evaluated and questioned. Ecological problems are never as simple as implied in using one or two guild axes. A close examination of bird communities in a ponderosa pine forest reveals little relationship between guilds or guild blocks and the responses exhibited by individual bird species or bird species groups. Response guilds changed from year to year without any obvious changes in vegetation. A three-year composite analysis shows a clearer picture of the responses of ponderosa pine forest birds to the overall interactions between structure, weather, competition, and so on. The six response groups in the composite analysis are species that (1) were absent in 1973 on most or all study plots and showed no preference for any forested site; (2) had their highest densities on the medium cut and light cut plots; (3) were absent in 1973 on most or all study plots and had their highest densities on the medium cut and light cut plots; (4) had their highest densities on the untreated, light cut, and medium cut plots; (5) had their highest densities on the untreated and light cut plots and were either absent or had greatly reduced densities on all other plots; and (6) were present only on the clearcut, except for the Rock Wren which was also on the medium cut and heavy cut plots. The overall correlation between species density and guild density was significantly higher for response guilds ( <0.05) than for any of the structural or functional guilds. The whole concept of guild management needs much more research and development before it can be recommended as a management tool.  相似文献   
296.
最近颁布的《建设项目环境保护管理条例》,使我国环境影响评价制度在法制化的轨道上又向前迈进了一步,对我国环境影响评价工作的开展将产生重大影响。本文就原《建设项目环境保护管理办法》与新条例作出分析比较。  相似文献   
297.
Health Impact Assessment (HIA) is increasingly being acknowledged as an important tool for considering the health implications of projects and programmes of activity at local, national and international levels. However, standard HIA tools can be difficult to apply when the policy of programme under consideration is particularly complex and intertwined or where significant time, resource and skill constraints are involved. This paper describes a Health Impact Review (HIR) of the plans for a major redevelopment of Central Manchester Hospitals (England). This approach to HIA drew not only from HIR but also from Integrated Impact Assessment (IIA) in order to produce a summary of the most significant health impacts of a policy, programme or project in a more timely and cost-effective way. This example highlights the potential for involving Local Authority Overview and Scrutiny Committees in the HIA process as a way of ensuring that the recommendations of HIA are mainstreamed as part of the ongoing development of projects.  相似文献   
298.
This paper presents some early thinking as to how the costs and benefits of HIA might be assessed. After considering previous work it uses a comprehensive HIA in Dulwich, SE London as a case study to highlight the possibilities and difficulties of collecting necessary data on costs and benefits. It then sets a context for developing a cost–benefit framework for analysis. The framework is viewed alongside the major types of economic evaluation. The paper concludes with a review of outstanding issues and considers how evidence on cost and benefit might make a difference in the application of HIA.  相似文献   
299.
刘淑秀  任晓梅 《干旱环境监测》1995,9(3):167-171,180
通过对18个乡镇的调查研究和现场采样分析,评价了乡镇工业的发展对农村环境影响的程度和范围,并对乡镇工业的发展方向和保护农村环境提出 了建议和保护措施。  相似文献   
300.
The impact of off-road vehicles on a desert ecosystem   总被引:1,自引:0,他引:1  
The effects of operating a 4-wheel drive truck in a 9-ha area of the Mojave Desert were evaluated. A truck was driven over the same 0.9-km track 21 times between November 1973 and May 1974. The vehicle was also driven randomly around the area (1.3 to 3.4 km) 17 times between December 1973 and May 1974.Spring densities of annual plants in ruts of the regular track (8/m2) were less than those in control areas (46–112/m2), but densities in randomly driven plots (39/m2) did not differ significantly from controls. Severity of damage to shrubs was directly related to intensity of driving in the area. About 58% of shrubs growing in the regular track sustained estimated damage ranging from 81 to 100%. In randomly driven areas only 6% of shrubs were damaged to this extent, while about 61 % sustained damage from 0 to 20%.Numbers and kinds of rodents in control and driven areas were similar before and after the experiment. More young rodents were trapped in the experimental plot than in the control area during July 1974, and this may have been promoted by basal sprouting of new growth by damaged shrubs. Estimates of numbers of side-blotched lizards indicated similar densities before, during, and after the experiment. Counts of whiptail lizards in control and experimental areas were the same after the experiment, but counts of gridiron-tailed lizards were much lower in the driven area.  相似文献   
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