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991.
ABSTRACT: A review of methods for planning-level estimates of pollutant loads in urban stormwater focuses on transfer of charac. teristic runoff quality data to unmonitored sites, runoff monitoring, and simulation models. Load estimation by transfer of runoff quality data is the least expensive, but the accuracy of estimates is unknown. Runoff monitoring methods provide best estimates of existing loads, but cannot be used to predict load changes resulting from runoff controls, or other changes of the urban system. Simulation models require extensive calibration for reliable application. Models with optional formulations of pollutant build up, washoff, and transport can be better calibrated and the selection of options should be based on a statistical analysis of calibration data. Calibrated simulation models can be used for evaluation of control alternatives.  相似文献   
992.
本文对西昌市大气污染现状进行调查分析,揭示了大气环境污染的特征及其变化规律,从宏观上提出了保护大气环境的对策。  相似文献   
993.
MFAM模型在河流水质污染模拟及预测中的应用   总被引:2,自引:0,他引:2  
张学成 《四川环境》1994,13(4):10-15
文中以时间序列分析为基础,介绍了均值生成函数这一崭新概念,并且经成份因子提取分析推导建立了模拟序列的数字模型(简记为MFAM),经对黄河下游花园口断面的1988-1989年实测水质污染指标溶解氧(DO),氨氧,化学耗氧量(COD),五日生化需氧量(BOD5)等序列模拟,结果表明MFAM模型能较好地模拟河流水质污染指标的变化趋势,拟合平均误差只有5.2-6.4%,MFAM模型应用于预测1990-1991年水质污染指标变化,结果表明预测精度达85%以上,文中最后得出结论:MFAM模型应用于河流污染模拟和预测,是完全可行且十分方便。  相似文献   
994.
石油工业废弃物处置及其生物治理趋势   总被引:4,自引:0,他引:4  
鉴于我国石油工作者对石油工业废弃物的普遍关注,现在介绍生物治理的基本概念及SPE石油工程师协会中有关含油污泥生物处置的途径及其突出优越性。生物液/固处理工艺(LST)是目前含油污泥处置现场最经济可行的处置方案。这种好氧的LST工艺过程,能够比较充分地代谢和降解石油污泥中的油和脂并大量除去多环芳烃类(PAH)化合物及其它有机化合物,明显地降低了石油废弃物对人、畜的毒害程度。其工艺较简单,操作也简易,凡经此工艺处理后的废弃物不留残毒和后患,因此早已被世界上先进国家的炼油业视为处理含油污泥的有效选择了。石油工业废弃物的生物防治和生物降解工艺较大程度地领先于目前我国现场正在执行的各种处理含油废弃物的处理工艺。  相似文献   
995.
我国环境问题日趋严重,环境污染和生态破坏已成为社会发展的制约因素。然而,有些企业忽视环境保护工作,取消或合并环境监测站,削弱环境监测力量。针对这种情况,从行业环境监测站的任务、作用和不可取代性方面阐述了强化行业环境监测站建设的必要性。  相似文献   
996.
ABSTRACT: Geographic Information Systems (GIS) were used to assess the relationships between land use patterns and the physical habitat and macroinvertebrate fauna of streams within similar sized watersheds. Eleven second or third order watersheds ranging from highly urbanized to heavily forested were selected along Lake Superior's North Shore. Land use patterns within the watersheds were quantified using readily available digital land use/land cover information, with a minimum mapping resolution of 16 ha. Physical habitat features, describing substrate characteristics and stream morphology, were characterized at sample points within each stream. Principle component and correlation analyses were used to identify relationships between macroinvertebrates and stream physical habitat, and between habitat and land use patterns. Substrate characteristics and presence of coarse woody debris were found to have the strongest correlations with macreinvertebrate assemblage richness and composition. Agricultural and urban land use was correlated with substrate characteristics. Algal abundance, associated with macroinvertebrate compositional differences, was correlated with housing density and non-forest land covers. The use of readily available spatial data, even at this relatively coarse scale, provides a means to detect the primary relationships between land use and stream habitat quality; finer-resolution GIS databases are needed to assess more subtle influences, such as those due to riparian conditions.  相似文献   
997.
ABSTRACT: A synoptic sampling of five surface-water sites in central Nebraska was conducted by the U.S. Geological Survey as part of its National Water-Quality Assessment Program during storm runoff in May 1992 to relate transport, yields, and concentrations of atrazine to environmental setting. Atrazine was the most extensively applied pesticide in the study unit. Atrazine transport was related to the size of contributing drainage area, quantity of atrazine applied, amount of precipitation, and volume of stream-flow. Estimated yields and mean concentrations of atrazine were related to the percentage of cropland in a drainage area. The largest estimated yields and mean concentrations of atrazine in surface water were associated from drainage areas with the highest percentage of cropland, and the smallest was associated with the smallest amount of cropland. Atrazine concentrations increased as streamflow increased but decreased at or near the time of peak streamflows, perhaps due to dilution. Atrazine concentrations then increased and remained elevated far into the stream recession. Atrazine is a regulated contaminant in finished public-water supplies. Large concentrations of atrazine could affect the management of public-water supplies because atrazine remains in solution in contrast to many other pesticides that are more easily removed.  相似文献   
998.
Environmental site assessment criteria were originally developed by organizations that focused, almost exclusively, on surface, subsurface, and pollution source contamination. Many of the hazards associated with indoor environments and building structures were traditionally not considered when evaluating sources and entities of environmental pollution. Since a large number of building materials are potentially hazardous, careful evaluation is necessary. Until recently, little information on building inspection requirements of environmental problems has been published. Traditionally, asbestos has been the main component of concern. The ever-changing environmental standards have dramatically expanded the scope of building surveys. Indoor environmental concerns, for example, currently include formaldehyde, lead-based paint, polychlorinated biphenyls, radon, and indoor air pollution. Environmental regulations are being expanded and developed that specifically include building structures. These regulatory standards are being triggered by an increased awareness of health effects from indoor exposure, fires, spills, and other accidents that have resulted in injury, death, and financial loss. This article discusses various aspects of assessments for building structures.  相似文献   
999.
许晓路  申秀英 《灾害学》1994,9(3):58-61
随着东阳市经济的迅速发展.由于人口数量增加,对自然资源的需求量越来越大,环境保护意识薄弱等原因,导致生态系统遭到破坏,林相单一、水土流失严重、洪旱灾害频繁、环境污染严重等灾害。据此,本文提出保护东阳市环境的对策。  相似文献   
1000.
The present study tested the separate and the interactive pollution effects of cadmium and mercury on the electrophoretically detected allelic isozyme frequencies of the enzyme phosphoglucose isomerase for two species of littoral marine gastropods —Littorina punctata andL. neritoides — and the enzyme amino peptidase forL. neritoides. Our results indicate differential survivorship of allelic isozyme genotypes specific for each type of pollutant and for their interaction, as well as trends common to all pollutants. Theoretically the results reflect the adaptive nature of at least some allozymic genotypes in these marine gastropods and seem inconsistent with the neutral theory of allozyme polymorphisms. Practically, the results reinforce earlier conclusions that changes in the frequency of allelic isozymes may be used as a genetic monitor of pollution.  相似文献   
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