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1.
选取黑龙江省源头水保护区作为研究对象,根据DEM数据对保护区内随机布设的水质监测点控制单元进行划分并提取单元内的相关指标建立监测点背景特性量化模型,基于量化结果提出地表水环境背景值监测方案,建立背景值数据库.选取研究区自然属性指标与空间属性指标,以空间叠置技术与聚类分析方法对研究区地表水进行背景值分区,最终将黑龙江省分为六大地表水水质背景值地理分区,并计算了各分区地表水环境背景值表征范围.表征范围显示:依据现行标准进行水质评价,保护区内水质背景值已超出Ⅱ类水质标准限值.因此,基于水质背景值研究成果提出了考虑背景值影响下的水环境质量评价方法,并将方法应用于研究区,结果表明方法切实可行且优于单因子评价法.研究成果可为区域制定背景值影响下的水环境评价方法提供科学的数据支撑与理论依据.  相似文献   
2.
A well sampling study was conducted to evaluate anempirical approach to classifying areasof land in California as vulnerable to ground watercontamination by pesticides (Troiano et al., 1994). Wells were sampled from sections of land that had noprevious detections of pesticideresidues. The sections had been classified into vulnerablesoil clusters or into a not-classified groupusing a procedure based on Principal Components Analysis(PCA). Grape, citrus, and olive growingareas of Fresno and Tulare Counties were targeted, areas wherepre-emergence herbicide residues hadbeen detected in well water. Overall, herbicide residues weredetected in 75 of 176 sampled wells, ahigh frequency of detection in relation to results fromprevious targeted well sampling studies. Sinceresidues were also detected in the not-classified group, theclassification procedure was modified usingan approach based on Canonical Variates Analysis (CVA). Moresections were classified intovulnerable soil clusters with the CVA approach than with thePCA method. Data from two otherexplanatory variables, depth to ground water and amount ofpesticide used per section, were includedto illustrate how additional information can be incorporatedinto this approach of identifying vulnerable areas.  相似文献   
3.
在环境空气监测点位优化中,为反映优化后点位的整体代表性,需要在允许的测定误差内以最少的测点反映区域内较长时期的整体污染水平、污染分布状况和污染趋势.本文以博山城区为例,利用地理变异系数法和Fisher最优分割法对所布设点位进行数理统计.该方法使用简便,分级自然,避免了诸多人为因素的影响,同时,优选结果具有较强的整体代表性.  相似文献   
4.
CharacteristicsofphosphoruschemistryanditsgeographicaldistributionintheHaiheRivervalley,NorthChinaJiangGaoming;HuangYinxiao;L...  相似文献   
5.
大连湾陆源污染物排海总量控制信息系统概念设计   总被引:2,自引:0,他引:2  
根据陆源污染物总量控制原理和沿海地区地方政府的经济条件,以大连湾为例,采用地理信息系统(GIS)技术,设计了排放入海湾的陆源污染物总量控制信息系统的概念模型,涉及系统建设的原则,数据类型,软件,硬件,用户界面和功能。为我国海湾污染物控制工作提供经济实用,先进的管理方法。  相似文献   
6.
GIS技术在环境影响评价中的应用   总被引:3,自引:0,他引:3  
为了研究地理信息系统(GIS) 在环境影响评价中的应用,在介绍地理信息系统的组成、类型、功能和应用领域的基础上,分析了GIS 技术在环境影响评价中的优势.从项目环境影响评价(EIA) 的局限性出发,简述了目前EIA 的研究现状,同时概述了地理信息系统(GIS) 的功能和应用,重点讨论了环境影响评价领域中应用地理信息系统的现状、必要性及其展望.  相似文献   
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8.
The use of the theoretical tools provided by proximity economics to address environmental questions, and the emergence of analyses revitalising the role of the spatial dimension in environmental problems, date from the late 1990s. This paper first aims to provide a review of the research conducted in this field and second to suggest some future research directions concerning the respective roles of geographical proximity and organised proximity in the production and management of environmental problems. First, it deals with the topic of ‘geographical proximity and land-use conflicts’, a topic that is currently the most researched in this field. This is followed by a discussion of the role of organised proximity in the regulation of environmental problems. The paper then explores the relation between the uncertainty associated with environmental issues and relations of organised proximity. Next it outlines a few possible research directions, focusing more particularly on the roles of geographical proximity as a mode of regulation of environmental problems, and on the possible role of organised proximity in their production. The concluding section draws an overview of the departures and extensions that have resulted from taking into account environmental issues in the paradigm of proximity economics.  相似文献   
9.
Individual risk analysis of high-pressure natural gas pipelines   总被引:1,自引:0,他引:1  
Transmission pipelines carrying natural gas are not typically within secure industrial sites, but are routed across land out of the ownership of the pipeline company. If the natural gas is accidentally released and ignited, the hazard distance associated with these pipelines to people and property is known to range from under 20 m for a smaller pipeline at lower pressure to up to over 300 m for a larger pipeline at higher pressure. Therefore, pipeline operators and regulators must address the associated public safety issues.This paper focuses on a method to explicitly calculate the individual risk of a transmission pipeline carrying natural gas. The method is based on reasonable accident scenarios for route planning related to the pipeline's proximity to the surrounding buildings. The minimum proximity distances between the pipeline and buildings are based on the rupture of the pipeline, with the distances chosen to correspond to a radiation level of approximately 32 kW/m2. In the design criteria for steel pipelines for high-pressure gas transmission (IGE/TD/1), the minimum building proximity distances for rural areas are located between individual risk values of 10−5 and 10−6. Therefore, the risk from a natural gas transmission pipeline is low compared with risk at the building separated minimum distance from chemical industries.  相似文献   
10.
Payne, Scott M. and William W. Woessner, 2010. An Aquifer Classification System and Geographical Information System-Based Analysis Tool for Watershed Managers in the Western U.S. Journal of the American Water Resources Association (JAWRA) 46(5):1003-1023. DOI: 10.1111/j.1752-1688.2010.00472.x Abstract: Aquifers and groundwater systems can be classified using a variety of independent methods to characterize geologic and hydraulic properties, the degree of connection with surface water, and geochemical conditions. In light of a growing global demand for water, an approach for classifying groundwater systems at the watershed scale is needed. A comprehensive classification system is proposed that combines recognized methods and new approaches. The purpose of classification is to provide groundwater professionals, policy makers, and watershed managers with a widely applicable and repeatable system that reduces sometimes cumbersome complex databases and analyzes to straightforward terminology and graphical representations. The proposed classification system uses basin geology, aquifer productivity, water quality, and the degree of groundwater/surface water connection as classification criteria. The approach is based on literature values, reference databases, and fundamental hydrologic and hydrogeologic principles. The proposed classification system treats dataset completeness as a variable and includes a tiered assessment protocol that depends on the quality and quantity of data. In addition, it assembles and catalogs groundwater information using a consistent set of nomenclature. It is designed to analyze and display results using Geographical Information System mapping tools.  相似文献   
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