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941.
ABSTRACT: Simulation of ground-water flow and fate of contaminants in the subsurface environment constitutes a major phase of most environmental assessment and site remediation studies. These simulation studies yield information on spatial and temporal distributions of contaminants in the subsurface media. An important use of this information is to conduct exposure assessment studies. Spatial and temporal distributions of both chemical concentrations and exposed populations render this integrated exposure analysis task rather difficult. Geographic Information Systems (GIS), on the other hand, provide a platform in which layered, spatially distributed databases can be manipulated with ease, thereby simplifying exposure analysis tasks significantly. In this paper, we describe procedures that combine the simulation models and demographic databases under a GIS platform to automate the exposure assessment phase of a typical health assessment study. Procedures developed herein significantly simplify the post-processing phase of the analysis, and render the overall task more ‘user friendly.’ A site-specific application is included as a demonstration of the proposed process.  相似文献   
942.
ABSTRACT: Current conventions for reporting analytical results from environmental samples brings the objectives of laboratory scientists into conflict with those of environmental scientists. The objective of chemical analyses is to provide estimates of the true composition of samples. Reported results must reflect the analytical uncertainty. Current conventions require left-censoring of those results below the Limit of Detection. The objective of statistical interpretation of environmental data is to provide estimates of the characteristics of ecosystems. Such statistical analyses are often confounded by left-censoring of analytical results. We review the different points of view and propose a compromise which recognizes these conflicting perspectives.  相似文献   
943.
This paper summarizes a study evaluating the acceptance and perceived performance of disposable cutlery made from starch-based biodegradable resins relative to nondegradable polystyrene cutlery. Two hundred forty-three sailors onboard three U.S. Navy vessels ate their lunch using either biodegradable cutlery made with resins manufactured by one of two commercial companies or polystyrene cutlery. The cutlery was rated on several sensory and performance dimensions as well as for overall acceptability. Results indicated that sailors rated both the biodegradable and the polystyrene utensils as easy to hold. There were also no differences in the perceived ease of using each of the spoons. However, compared to the polystyrene utensils, both types of biodegradable utensils were viewed as less sturdy, as having a less attractive color, and as being less acceptable overall. The biodegradable forks and knives were also rated as more difficult to use for piercing and cutting food than the polystyrene ones. In addition, several significant differences emerged between the two types of biodegradable cutlery. The results are discussed in terms of the need for continued consumer testing of products developed from biodegradable polymeric materials.  相似文献   
944.
We are witnessing a growing concern with the global dimension of many environmental issues, reflected in the increase in the number and significance of international environmental organizations. Yet there is no internationally applicable strategy for environmental research which is management oriented. A new type of research policy, which integrates ideas derived from environmental and human ecology, is required in order to deal with cultural and ecological diversity and their interactions as reflected in the ecology of landscapes. The newly defined concept of environmental health is proposed to fill this gap. This concept integrates the latest developments in landscape evolutionary ecology and environmental health, bringing out a conflict between making the environment conducive to human health and increasing the available options for supporting the essential biological and ecological processes of the environment. Lessons derived from the evolution of human environments are used in order to illustrate how health may become un umbrella for developing an environmental research policy, which could also serve as a catalyst for international environmental projects.  相似文献   
945.
Changes in global patterns of grain production have affected the profitability of commercial, cash-crop agriculture in North America. The current financial crisis has highlighted a perceived conflict between the priorities of (1) strengthening net farm profit, (2) maintaining the productive potential of the land base, (3) enhancing the health and cohesiveness of the agricultural community, and (4) addressing societal demands for safe foodstuffs. Reducing input costs by reducing the need for privately owned machinery can minimize the scale-dependence of agricultural practices, as illustrated with examples involving silage and intensively managed pasture in Ontario. This approach could improve farming opportunities for nontraditional, part-time farmers, and at the same time, create a niche for professional custom operators and managers. Enhancing the viability of nontraditional farm operations, a historically neglected component of the farming community, as well as commercial farms is viewed as one approach to sustaining and improving both the agricultural land base and the agricultural community. Applying resource-extensive rather than resource-intensive approaches to forage management reveals that these apparently divergent priorities are, in fact, interlocking pieces of the same puzzle.  相似文献   
946.
回顾了国内外区域开发环境管理的发展历程,简要论述了区域环境规划与区域开发环境影响评价在区域开发环境管理中的作用和地位以及两者的相互关系。  相似文献   
947.
五氯酚对环境污染及居民健康影响研究   总被引:2,自引:0,他引:2  
中国长期以来使用五氯酚纳盐杀灭亡血吸虫的中间宿主──—钉螺.为评价它对环境的污染及居民健康危害,1990-1993年在我省开展了五氯酚环境污染及对居民健康影响研究.在研究区采集环境样品(空气、水体、土壤及底泥、蔬菜、肉、蛋、鱼等)共173份;生物材料(人血、尿)共457份,分析五氯酚浓度.结果在明,在五氯酚使用区,环境中PCP浓度稍高于对照区,而生物材料尿、血中PCP浓度明显高于对照区.全血胆碱脂酶活性用药区明显低于对照区,统计学分析有显著差异(P<0.001),证实了长期低剂量使用可造成环境及生物蓄积.  相似文献   
948.
微生物法和微生物生态法作为生物治理方案的两大类型,已日益受到环保工作者的重视。这两种类型的治理方法各有特点,各有利弊。如何选择使用?主要取决于污染场所中污染形成的时间长短、污染程度、污染物浓度、污染物中是否含有污水、是否需要快速治理等。应明确指出的是,采用生物治理法虽可在多种情况下大大降低污染物的浓度,但从长远来看,还不能单纯依靠降低污染物的排放浓度,而是应从低浓度污染物对人和环境产生的长期影响着眼,制定出一套治理标准,这样才能准确评价生物治理技术在环境保护中所起的真正作用。  相似文献   
949.
为确保炼油厂设备安全而稳定地运行,各生产装置都要定期进行停工检修,在此期间排放的污染物对环境将产生一定的影响。停工检修中的环保工作包括实施环保措施;加强环境管理;并且将2000m~3隔油池由一间式变为两间式,提高污水处理率和达标率。  相似文献   
950.
This article investigates the impact of ISO 14001 certification on the compliance with environmental regulations by Korean companies. The impact of ISO 14001 certification on the industry was studied through a questionnaire survey and the compliance of environmental regulations were investigated using government-released data. The motivation for an environment management system was a result of the current international situation and the need to maintain fair competition. ISO 14001 certification has been recognized as an essential strategy for industrial competition and to improve company/product recognition. The certified and non-certified companies' environmental regulation violation (ERV) rates were 3.5% and 11.6%, respectively, in 1997. In 1998, the ERV rate had an eight-time difference with 1.0% and 8.5% for certified and non-certified companies, respectively. Annual regulation violation rates were reduced from 3.5% in 1997 to 1.0% in 1998 with certified companies and from 11.6% in 1997 to 8.5% in 1998 with their non-certified counterparts, respectively. ISO 14001 certified companies showed more improvement than non-certified companies in regards to environmental performance.  相似文献   
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