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121.
分析了模糊综合评判在水质评价中的缺陷,将模糊数学中的贴近度与经典的Euclidean距离结合,提出Euclidean贴近度水质评价法。结果表明,该评价方法具有科学性、合理性,并且精度高,简单实用。 相似文献
122.
应用模糊综合指数法对伊犁河(伊宁段)水质的综合评价 总被引:3,自引:0,他引:3
模糊数学法对伊犁河(伊宁段)水质进行综合评价时,由于分别采用地面水环境质量标准中五类标准值的平均值及其中三个标准值,计算后的结果不一致,而模糊综合指数法避免了这类问题的出现,计算结果比较满意.从而表明,该法是对模糊数学法的进一步改进. 相似文献
123.
124.
乌伦古湖水质现状及污染防治对策 总被引:7,自引:0,他引:7
着重对乌伦古湖所监测的项目作了全面系统的分析,评价了该湖的水环境质量,指出乌伦古湖水质的主要问题是严重咸化,这是该湖可持续发展的最大障碍。并指出做好湖区规划,增加水源供给,加强污水处理和湿地建设,是乌伦古湖未来发展的有利措施。 相似文献
125.
Diazinon contamination of California's rivers has resulted in placing several rivers on the federal Clean Water Act § 303d list of impaired waterways. Impaired water body listing requiresthe development of Total Maximum Daily Loads (TMDL). Previous studies identified stormwater related diazinon pulses in California rivers. This study was conducted to monitor diazinonconcentrations in the Sacramento River watershed after rainfallevents, to ascertain whether pulses could be identified and, ifconcentrations of concern were observed, to estimate loadings anddetermine geographic origins of the insecticide. TMDL developmentrequires knowledge of contaminant sources, loadings, and geographic origins. Flow and diazinon concentrations peaked in the Sacramento River at Sacramento after the three largest stormsduring January and February 1994. Diazinon concentrations peakedconsequent to each of three storms. Diazinon concentrationsmeasured in the Sacramento River at Sacramento exceeded theCalifornia Department of Fish and Game acute and chroniccriteria for protection of aquatic life during January andFebruary for nine and nineteen days, respectively. Multipleexceedances were observed throughout the watershed. Diazinon loading and geographic origin differed with each of the three storms. The design of this study provides a useful template for others attempting to identify loadings and sources of contaminants in surface waters and to rectify aquatic ecosystemcontamination from various land use practices. 相似文献
126.
Turalioğlu FS 《Environmental monitoring and assessment》2005,104(1-3):119-130
Sulphur dioxide and PM10 levels are investigated in Erzurum during the periods of 1990–2000 heating season to assess air pollution level. For that reason, emissions of sulphur dioxide and particulate matter were calculated by using consumption of fuels and Turkish emission factors. These emission values were evaluated together with air pollution levels, which were measured at six stations in Erzurum atmosphere during 1990–2000 winter periods. Results reveal that in 1990–1994 heating period, there is an increasing trend in the emissions and air pollution levels over Erzurum, and the air quality limits were not met. The daily 24 h limit (short-term limit) was exceeded 127 days in 1992–1993 winter period. The reason for this increase was found to be the switching to use of low-quality fossil fuels instead of cleaner ones. Results also indicated that there was a considerable decrease in emissions of air pollutants and air pollution levels after 1995. This can be explained by the consumption of more high-quality fossil fuels. The correlation coefficient of SO2 with PM10 is obtained as r2 = 0.85, which is a high value supporting the idea that both pollutants are emitted from the same source. 相似文献
127.
通过对新疆著名旅游城市吐鲁番的空气环境、水环境、声环境、景观生态环境等环境质量存在的问题进行分析,针对性地提出了相应的环保对策及建议,为吐鲁番市的环境保护工作提供参考。 相似文献
128.
A. Haurie J.J.E. Kübler A. Clappier H. van den Bergh 《Environmental Modeling and Assessment》2004,9(1):1-12
A method is proposed to build integrated models (also called Metamodels) aimed at quantifying the economic efficiency of air quality policies. This Metamodeling approach is based on the coupling of two complementary models, that operate at different scales in space and time, and which represent the economic and the physical and chemical processes, respectively. The joint consideration of the physico-chemical and techno-economic structure of the pollution control problems permits a comprehensive evaluation of air pollution abatement strategies. The motivating pollution control problems include urban-regional air quality management through efficient energy and traffic control policies. A pilot study, exploiting data collected in the Geneva canton (Switzerland), is used to demonstrate the potential of the approach. 相似文献
129.
J. Franzaring 《Environmental monitoring and assessment》1997,46(3):209-220
Up to now only very few studies in biomonitoring of organic air pollutants have been published taking into account the strong influence mean temperatures have on the accumulation process into plants during the course of the exposition. Temperature governed sorption as well as the plants vitality pose a major source of uncertainty making inter-study comparisons difficult. Different surface-to-volume ratios of plant foliage lead to strongly varying concentration effects in different plant species. Moreover a plants content of waxes and lipids must be considered in order to relate xenobiotic concentrations to the compounds being most efficient in the bioaccumulation process. Some of these factors are evaluated in regard to the use of plants as biomonitors for organic air pollutants. Another aim is to deduce the mean ambient gas phase concentrations from PAH concentrations determined in the biomonitor plants using vegetation-air partitioning coefficients which have been corrected for temperature dependent sorption as well as the plants lipid content. Restrictions of such approaches and methods of biomonitoring in general are discussed. 相似文献
130.
几种土壤质量评价方法的比较 总被引:20,自引:0,他引:20
分别用T值分级法,综合指数法,模糊数学综合评判法,灰色聚类法,等斜率灰色聚类法,宽域灰色聚类法对湖南某地10个监测点的土壤质量现状进行评价,通过比较,认为宽域灰色聚类法较好。 相似文献