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991.
ABSTRACT: The Illinois v. Milwaukee Federal District Court decision is the most far reaching application yet of the federal common law of nuisance to interstate water pollution conflicts. Although a Federal Appelate Court recently rescinded part of the district court decision, Milwaukee must still upgrade its metropolitan sewage system to a level beyond that required by federal and state regulations. The improvements must be completed with or without federal aid. The case points out the apparent inability of the Clean Water Act, the most comprehensive federal legislation affecting the nation's water quality, to deal with certain interstate water quality conflicts. The Milwaukee decision could set a precedent for similar settlements elsewhere which may in turn affect the U.S. Environmental Protection Agency's water quality clean up program. A more integrated, ecosystem conscious approach to management of shared water resources (e.g., the Great Lakes) would help reduce the need for court decisions like Illinois v. Milwaukee.  相似文献   
992.
ABSTRACT: A method of project planning for systematically assessing and recording impacts of alternative timber harvest startegies for subareas of a sale planning area is presented. This method uses an interdisciplinary team composed of specialists and decisionmaker to develop and analyze treatment alternatives and uses impact prediction matrices with explicit evaluation criteria to illustrate and record ratings of impacts on resource factors. The method is a system for organizing, for discovering appropriate alternatives, for facilitating interaction, and for documenting environmental analysis. It provides for decisionmaker control over the project, for exchange of value perspectives, and for reduction in conflict between specialists. The quality of decisions which result from the method presented depends upon the information available and the effectiveness of interaction between all members of the interdisciplinary team.  相似文献   
993.
ABSTRACT: Most of California's precipitation falls at the wrong place in the wrong season in relation to the water needs. Redistribution and regulation are essential. Aquifer systems – groundwater basins – can provide a share of the future cyclic storage regulation. There are some differences in management concepts in using a full basin in comparison with a partially dewatered basin. Legal, water quality, and physical impacts on aquifer systems, including subsidence, are concerns. Storage may be for the benefit of overlying water users or for distant areas. Extraction during dry periods or recharge methods will require careful planning. Existing rights and uses and equitable treatment of all parties must be assured. Financial compensation may be involved. Changes in methods of operation or degree of self-determination by affected water agencies will require committed watermanship to resolve. Legislation or amendments to organic acts may be needed but much can be accomplished within existing statutes. Environmental impacts which can be avoided by not using large surface storage sites are important. Energy for pumping will be a key consideration. About 40 percent of California is underlain by aquifer systems. This resource offers major potential in overcoming the maldistribution of natural water resources.  相似文献   
994.
ABSTRACT: The environmental effects of flood control channel modifications such as clearing and snagging, straightening, enlargement, and/or paving can be quite severe in some cases. Information review reveals that several environmental features have been incorporated into the design, construction, operation, or maintenance of recent flood control channel projects to avoid adverse environmental impacts and enhance environmental quality. Typically, these features have been proposed by conservation agencies and designed with minimal quantitative analysis. Environmental features for channel projects include selective clearing and snagging techniques, channel designs with nonuniform geometry such as single bank modification and floodways, restoration and enhancement of aquatic habitat, improved techniques for placement of excavated material, and revegetation.  相似文献   
995.
ABSTRACT: The major objectives are (1) to identify the problems involved in measuring the environmental impacts of public projects from selected perspectives, and (2) to elaborate a sociological approach used in an empirical investigation in that respect. The construct of environmental impact of a planned action is generally operationalized from different perspectives and with different methodological emphases in the various disciplines. Even the term environment does not elicit agreement among users as to its exact meaning. Although there has been a steady increase in the number of studies from a sociological perspective concerning environmental problems, there is lack of sociological counsel in writing environmental impact statements. Overall, we lack sociological methodology and operational procedures for that purpose. In an attempt to bring some empirical focus to this field, attitudinal measures employed to discover how residents of a river basin perceived negative and positive environmental impacts of a proposed watershed development project are reviewed. These come from a study of creation of the Cooper Reservoir and Dam in Texas. Data on 343 heads of households m the selected areas were collected through structured questionnaires with items on personal information, a vested interest scale, a knowledge of the project scale, and an environmental impact scale. Data show that perception of impacts by residents is influenced significantly by degree of their vested interests involved. Variables for inclusion in a sociological model of environmental impact are suggested.  相似文献   
996.
遥感在生态与环境监测中的主要应用领域   总被引:4,自引:2,他引:4  
遥感是一种以物理手段、数学方法和地学分析为基础的综合应用技术 ,具有宏观、综合、动态和快速的特点。在解决宏观尺度的环境问题时 ,卫星遥感可重复获取多种空间、不同时相和不同波谱分辨率的地球信息 ,是适宜于调查和研究这些主题的唯一的、最有效的工具。本文通过对遥感在环境与生态监测的主要应用领域进行概要阐述 ,旨在抛砖引玉 ,推动遥感在环境与生态监测中的广泛应用。  相似文献   
997.
联苯代谢对微生物的生长胁迫及分裂抑制   总被引:1,自引:0,他引:1  
以联苯/多氯联苯降解菌株R04(Rhodococcus sp.R04)和几种模式微生物为研究对象,利用高效液相色谱、荧光显微镜、扫描电子显微镜等分析微生物在联苯及其代谢物培养条件下细胞分裂和形态的变化.结果表明联苯及其代谢产物对红球菌R04和几种模式微生物细胞的分裂有抑制作用,并对部分微生物形态有影响.与前体-联苯及其代谢产物2-羟基-6-酮基-6-苯基-2,4-己二烯酸相比,2,3-二羟基联苯对G+、G-细菌,或是酵母细胞分裂都有较强的抑制和形态的改变.2,3-二羟基联苯导致R.R04和缺陷型R.R04细胞形成不完整隔膜的比例增加;造成96.4%的大肠杆菌BL21细胞表面凹陷,胞质内容物流失,菌体体积缩小;导致枯草芽孢杆菌89.6%的细胞体积明显缩小;导致金黄色葡萄球菌基本没有细胞能形成完整的分裂隔膜;导致红酵母细胞能进行出芽生殖的比例从64.2%降低到19.3%,但对其细胞形态无明显改变.联苯代谢物2,3-二羟基联苯对红球菌R04及其它微生物细胞分裂和增殖的抑制作用比其前体-联苯强,建议在研究环境化合物与微生物互作时,应考虑环境化合物代谢的毒性效应.  相似文献   
998.
郭晓东  郝晨  王蓓 《中国环境科学》2019,39(10):4456-4463
以湖北省为例,基于压力-状态-响应(PSR)模型构建环境绩效评估指标体系,运用空间自相关和标准差椭圆对湖北省各地区绩效指数空间特征及影响因素进行探讨,结果显示:湖北省各地区环境绩效指数(EPI)均高于60,但普遍处于中等水平,良好及优秀所占比例低.EPI较高的地区主要位于湖北省西部和中部,压力和状态指数从西至东递减,响应指数则呈现东部高于西部高于中部的态势.状态指标绩效指数在空间上显著正相关,即环境质量状况较好(或较差)的地区在空间上集聚.EPI及二级指标绩效指数均以西北-东南为布局方向,且EPI椭圆重心较于基准重心偏向于西南方向.各地区环境指数除受到资源禀赋的影响外,还与城镇化率和人口密度显著相关.  相似文献   
999.
建设世界旅游精品是张家界制定的旅游业发展的战略目标,一流的旅游环境条件是实现这一目标的必备条件。然而,张家界目前的旅游环境与世界旅游精品存在差距,环境管理中存在基础性工作、基础性研究比较薄弱、制度不够健全等方面的问题,影响了环境管理效率。在分析研究张家界环境管理中存在问题的基础上,针对性地提出保护、改善环境的对策,是实现世界旅游精品战略目标的基础工作。  相似文献   
1000.
Environmental quality for environmental health has been examined visually by describing general conditions and drinking water supply, sanitation and solid waste treatment conditions and practices in six South-East Asian villages with a dense population. The environmental review was supplemented by discussions with local people and political and administrative decision makers. Some drinking water analyses were done in order to show the water quality to the local people. The quality of the general conditions and the conditions and practices of drinking water supply, excreta disposal and solid waste treatment practices have been graded with the grading system presented below. The grading could be done in 1 or 2 days in each area by two persons, of which one was an environmental scientist and the other a social scientist, who also knew the local culture and worked as a translator.  相似文献   
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