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161.
Status and fuzzy comprehensive assessment of combined heavy metal and organo-chlorine pesticide pollution in the Taihu Lake region of China 总被引:13,自引:0,他引:13
The status of combined heavy metal and organo-chlorine pesticide (OCPs; i.e. HCH and DDT) pollution was investigated and the soil environmental quality of the Taihu Lake watershed, one of the most developed regions in China, was evaluated using a fuzzy comprehensive assessment. Statistical analyses showed the presence of combined pollution in the soil. At many sampling sites, heavy metal concentrations were above corresponding background values, indicating the effects of extraneous pollutants. It has been over 20 years since China banned the use of OCPs, but they can still be found in soil samples of this region. HCH levels at all investigated sites were below the Chinese Environmental Quality Standard for Soils. Fuzzy comprehensive assessment showed that the overall soil quality in this region could be categorized as class I. Nevertheless, the high coefficients of variation for levels of DDT, Cd and Hg indicated the existence of some point-source pollution. Continuous monitoring and further studies of the region are recommended to prevent pollution of farmland from these sources. 相似文献
162.
Development and Adoption of a Simple Nonpoint Source Pollution Model for Port Phillip Bay,Australia 总被引:1,自引:0,他引:1
New computing tools and approaches allow tailored development of software to meet the needs of environmental managers. The processes required for such tailoring fit well with adaptive management concepts where, as knowledge and system understanding develop among managers, the software can be developed or replaced to match. This paper reports on development and adoption of a simple nonpoint source pollution modeling tool, including technical aspects of data support for modeling and social aspects of software design. The software, named FILTER, used a unit load model to generate expected pollutant loads from subcatchments of Port Phillip Bay, Australia. Monitoring data were used for calibration to modify the delivery of generated pollutants to receiving waters. Spatial, tabular, and charting software components were used to provide alternative forms of output visualization. FILTER was developed using a process that resulted in manager-stakeholders taking responsibility for setting of model parameter values and operation of the user interface, thereby encouraging uptake. The inclusive development process, tailoring of the software to manager needs and styles of usage, and matching of model complexity to data and knowledge, resulted in a successful application that has become the current agreed system representation among disparate stakeholder organizations. 相似文献
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164.
Wayne W. Lapham Michael J. Moran John S. Zogorski 《Journal of the American Water Resources Association》2000,36(6):1321-1334
ABSTRACT: The U.S. Geological Survey (USGS) has compiled a national retrospective data set of analyses of volatile organic compounds (VOCs) in ground water of the United States. The data are from Federal, State, and local nonpoint‐source monitoring programs, collected between 1985–95. This data set is being used to augment data collected by the USGS National Water‐Quality Assessment (NAWQA) Program to ascertain the occurrence of VOCs in ground water nationwide. Eleven attributes of the retrospective data set were evaluated to determine the suitability of the data to augment NAWQA data in answering occurrence questions of varying complexity. These 11 attributes are the VOC analyte list and the associated reporting levels for each VOC, well type, well‐casing material, type of openings in the interval (screened interval or open hole), well depth, depth to the top and bottom of the open interval(s), depth to water level in the well, aquifer type (confined or unconfined), and aquifer lithology. VOCs frequently analyzed included solvents, industrial reagents, and refrigerants, but other VOCs of current interest were not frequently analyzed. About 70 percent of the sampled wells have the type of well documented in the data set, and about 74 percent have well depth documented. However, the data set generally lacks documentation of other characteristics, such as well‐casing material, information about the screened or open interval(s), depth to water level in the well, and aquifer type and lithology. For example, only about 20 percent of the wells include information on depth to water level in the well and only about 14 percent of the wells include information about aquifer type. The three most important enhancements to VOC data collected in nonpoint‐source monitoring programs for use in a national assessment of VOC occurrence in ground water would be an expanded VOC analyte list, recording the reporting level for each analyte for every analysis, and recording key ancillary information about each well. These enhancements would greatly increase the usefulness of VOC data in addressing complex occurrence questions, such as those that seek to explain the reasons for VOC occurrence and nonoccurrence in ground water of the United States. 相似文献
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167.
对广东北江镉污染事件的立法评析—兼评《水污染防治法》 总被引:1,自引:0,他引:1
李博 《中国环境管理干部学院学报》2009,19(2):14-18
本文选取环境问题比较突出的水污染领域进行集中探讨,从分析“广东北江镉污染”这一具有典型意义的水污染突发事件入手,首先分析导致北江污染事件发生的具有普遍意义的共性原因,然后总结1996年《水污染防治法》存在的问题并提出修订法律的必要性,最后通过对2008年新修订的《水污染防治法》相关制度的解读与评说,来提出进一步完善新法的一些立法建议。 相似文献
168.
李楠 《中国环境管理干部学院学报》2009,19(3):67-69,73
河北省1998年-2005年的水环境质量监测数据分析表明:河北省地表水污染恶化趋势基本得到遏制,但部分地区水污染矛盾仍很突出;水体总体污染减轻,但氨氮污染有加重趋势;主要湖(库)水水质稳定,但普遍呈不同程度的富营养化。在此基础上,分析了地表水污染的原因,并提出了河北省改善地表水环境污染的对策与措施。 相似文献
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170.
Policy makers often must rely on the cumulative impact of independent actions taken by local landowners to achieve environmental
goals. The connection between policy, regulation, and local action, however, is often not well understood and, thus, the impact
of proposed policies may be difficult to predict. In this study we evaluate the effectiveness of alternative policy scenarios
for agricultural set aside programs (e.g., the conservation reserve program administered by the United States Department of
Agriculture) in reducing nonpoint pollution. Two alternative policy scenarios are developed and analyzed; one based on the
erodibility index (detachment), the other sediment yield (transport). An estimate of the cumulative impact of associated land
use change on nonpoint pollution is made using the AGNPS distributed parameter watershed model. This work is completed within
the Cypress Creek watershed in southern Illinois. An analysis of the resulting data suggests that the most efficacious regulatory
strategy for achieving nonpoint water pollution goals depends, in part, on place-specific land use patterns. This conclusion
provides a solid argument for place-based regulatory strategies. 相似文献