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61.
长江流域等重污染行业经济和污染贡献率剖析 总被引:4,自引:0,他引:4
应用"污染贡献率"这一指标,分析了长江、黄河、珠江和松花江流域COD和氨氮排放的重污染行业以及地区分布,指出了各流域COD和氨氮排放的控制重点.同时分析了各流域重污染行业的经济贡献率,最后结合行业的污染贡献率和经济贡献率以及行业在地区所占的比例,提出了几点重要的结论. 相似文献
62.
对室内装饰装修材料检测中甲醛分析方法的研究 总被引:2,自引:0,他引:2
目前室内装饰装修材料中甲醛含量的检测有六个类别,分析方法不统一,且没有一定的质量控制措施.文章对分析方法进行了改进,并且研究用水中的甲醛标样来对检测过程进行质量控制,结果较好. 相似文献
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Mehaffey MH Nash MS Wade TG Ebert DW Jones KB Rager A 《Environmental monitoring and assessment》2005,107(1-3):29-44
The Catskill/Delaware reservoirs supply 90% of New York City’s drinking water. The City has implemented a series of watershed protection measures, including land acquisition, aimed at preserving water quality in the Catskill/Delaware watersheds. The objective of this study was to examine how relationships between landscape and surface water measurements change between years. Thirty-two drainage areas delineated from surface water sample points (total nitrogen, total phosphorus, and fecal coliform bacteria concentrations) were used in step-wise regression analyses to test landscape and surface-water quality relationships. Two measurements of land use, percent agriculture and percent urban development, were positively related to water quality and consistently present in all regression models. Together these two land uses explained 25 to 75% of the regression model variation. However, the contribution of agriculture to water quality condition showed a decreasing trend with time as overall agricultural land cover decreased. Results from this study demonstrate that relationships between land cover and surface water concentrations of total nitrogen, total phosphorus, and fecal coliform bacteria counts over a large area can be evaluated using a relatively simple geographic information system method. Land managers may find this method useful for targeting resources in relation to a particular water quality concern, focusing best management efforts, and maximizing benefits to water quality with minimal costs.The United States Environmental Protection Agency through its Office of Research and Development funded and managed the research described here. It has been subjected to Agency’s administrative review and approved for publication as an EPA document. 相似文献
67.
Evaluation of Water Quality in the Chillán River (Central Chile) Using Physicochemical Parameters and a Modified Water Quality Index 总被引:4,自引:0,他引:4
Debels P Figueroa R Urrutia R Barra R Niell X 《Environmental monitoring and assessment》2005,110(1-3):301-322
The Chillán River in Central Chile plays a fundamental role in local society, as a source of irrigation and drinking water,
and as a sink for urban wastewater. In order to characterize the spatial and temporal variability of surface water quality
in the watershed, a Water Quality Index (WQI) was calculated from nine physicochemical parameters, periodically measured at
18 sampling sites (January–November 2000). The results indicated a good water quality in the upper and middle parts of the
watershed. Downstream of the City of Chillán, water quality conditions were critical during the dry season, mainly due to
the effects of the urban wastewater discharge. On the basis of the results from a Principal Component Analysis (PCA), modifications
were introduced into the original WQI to reduce the costs associated with its implementation. WQIDIR2 and WQIDIR, which are both based on a laboratory analysis (Chemical Oxygen Demand) and three (pH, temperature and conductivity), respectively,
four field measurements (pH, temperature, conductivity and Dissolved Oxygen), adequately reproduce the most important spatial
and temporal variations observed with the original index. They are proposed as useful tools for monitoring global water quality
trends in this and other, similar agricultural watersheds in the Chilean Central Valley. Possibilities and limitations for
the application of the used methodology to watersheds in other parts of the world are discussed. 相似文献
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乌鲁木齐市汽车尾气排污现状及防治对策探讨 总被引:1,自引:0,他引:1
对乌鲁木齐市在用车辆进行了路抽检调查,通过大量数据分析,得出乌鲁木齐市目前汽车尾气排放情况仍令人担忧,治理工作不容忽视。 相似文献
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