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901.
A multiple regression model of atmospheric deposition of salt, combined with geographic information systems (GIS) data on
four classes of roads, is used to predict sodium concentrations in 162 randomly chosen streams in Massachusetts. All four
classes of roads, as well as atmospheric deposition, were found to be highly significant in a model that explains 68% of the
observed variation in sodium concentration. The highest salt loading rates are associated with interstate and major state
roads with an estimated 22,500 and 17,700 kg of salt per kilometer, respectively. Our mass balance calculations indicate road
salt is the major source of salt to the streams in Massachusetts.
We examined some of the common statistical problems associated with the use of multiple regression for this type of analysis.
Our confidence in the accuracy of the loading rates estimated above are limited by the collinear nature of environmental data
and uncertainties related to model specification. Our results suggest multiple regression techniques can lead to overconfidence
in the accuracy of the estimated loading rates and thus should not be used as the basis for policy unless the model is validated. 相似文献
902.
Groundwater contamination by agricultural chemicals is a major environmental pollution issue nation-wide. The regulatory agencies of towns and counties face the problem of finding a methodology for assessing the ground-water contamination potential of a large number of agricultural pesticides. Because of the spatial nature of the problem and the limited data availability for comprehensive pesticide movement models, a contamination potential index was employed for preliminary assessment. A specially designed geographic information system was used to create ground-water contamination likelihood maps for a 1500 km2 area. The results suggest that this methodology can be used successfully for evaluating the relative contamination potential of a large number of pesticides over large areas with limited input data. A tentative approach for using this method for monitoring and registration of pesticides is also discussed. 相似文献
903.
W. Andrew Marcus 《Environmental management》1989,13(6):703-713
A number of state and federal agencies are presently attempting to develop management strategies for contaminated aquatic sediments. Until now, research and debate on sediment guidelines and regulations has focused almost exclusively on biological and chemical techniques for determining when sediments pose an environmental risk. Hydrologic factors must also be considered, however, if these biochemically based techniques for establishing sediment quality standards are to be feasible. Hydrologic issues that need to be addressed include how to define the boundaries of the aquatic environment, the scope of sediment regulations in ephemeral waters, regulations and sampling procedures in heterogeneous sediments, and timing of samples for monitoring and enforcement purposes 相似文献
904.
The concern of this paper is a review of the urban environmental degradation and the current approach by the military (environmental task force) in solving the problem. It is based on the experience of a few states in Nigeria. The paper proposes a comprehensive urban planning approach which should be integrated with an awareness campaign. 相似文献
905.
B. Bowonder 《Environmental management》1986,10(5):599-609
Environmental problems are becoming serious in India because of the interacting effects of increasing population density, industrialization and urbanization, and poor environmental management practices. Unless stringent regulatory measures are taken, environmental systems will be irreversibly degraded. Lack of political commitment, lack of a comprehensive environmental policy, poor environmental awareness, functional fragmentation of the public administration system, poor mass media concern, and prevalence of poverty are some of the major factors responsible for increasing the severity of the problems. Environmental problems in India are highly complex, and management procedures have to be developed to achieve coordination between various functional departments, and for this, political leaders have to be convinced of the need to initiate environmental protection measures. 相似文献
906.
Daily PM_(2.5)(particulate matter with an aerodynamic diameter of below 2.5 μm) mass concentrations were measured by gravimetric analysis in Chinese Research Academy of Environmental Sciences(CRAES), in the northern part of the Beijing urban area, from December 2013 to April 2015. Two pairs of Teflon(T1/T2) and Quartz(Q1/Q2) samples were obtained, for a total number of 1352 valid filters. Results showed elevated pollution in Beijing,with an annual mean PM_(2.5)mass concentration of 102 μg/m~3. According to the calculated PM_(2.5)mass concentration, 50% of our sampling days were acceptable(PM_(2.5) 75 μg/m~3), 30% had slight/medium pollution(75–150 μg/m~3), and 7% had severe pollution( 250 μg/m~3). Sampling interruption occurred frequently for the Teflon filter group(75%) in severe pollution periods,resulting in important data being missing. Further analysis showed that high PM_(2.5)combined with high relative humidity(RH) gave rise to the interruptions. The seasonal variation of PM_(2.5)was presented, with higher monthly average mass concentrations in winter(peak value in February, 422 μg/m~3), and lower in summer(7 μg/m~3 in June). From May to August, the typical summer period, least severe pollution events were observed, with high precipitation levels accelerating the process of wet deposition to remove PM_(2.5). The case of February presented the most serious pollution, with monthly averaged PM_(2.5)of 181 μg/m~3 and 32% of days with severe pollution. The abundance of PM_(2.5)in winter could be related to increased coal consumption for heating needs. 相似文献
907.
908.
铜仁汞矿区土壤汞污染现状调查研究 总被引:1,自引:0,他引:1
为了进一步对废弃汞矿污染区的生态环境进行跟踪调查及科学的评价,2015年通过对铜仁市废弃汞矿区周围的稻田、旱田及菜地土壤汞污染现状调查分析。采用S型随机抽样方式,并使用原子荧光光度法对研究对象进行分析。结果表明:万山镇、云场萍及路腊村汞矿区稻田土壤总汞(THg)含量平均值分别为123.75、79.33、21.89 mg/kg;其旱田土壤THg含量平均值分别为:117.20、73.34、19.90 mg/kg;其菜地土壤THg含量平均值分别为129.40、81.78、26.50 mg/kg;且,万山汞矿区甲基汞(Me Hg)含量平均值分别为6.48(稻田)、4.80(旱田)、6.40μg/kg(菜地);云场萍汞矿区Me Hg含量平均值分别为3.73(稻田)、2.47(旱田)、6.40μg/kg(菜地);路腊村汞矿区Me Hg含量平均值分别为1.92(稻田)、0.87(旱田)、2.47μg/kg(菜地)。以上结果说明万山废弃汞矿区的污染程度高于云场萍废弃汞矿区及路腊村废弃汞矿区。 相似文献
909.
以某个砒霜厂旧址为研究对象,分析场地的重金属污染特征。结果表明,该场地受到砷、铜、铅、镉和锌等重金属污染,其中,砷污染指标超过评价标准值达7 199倍;基于《展览会用地土壤环境质量评价标准(暂行)》条件下,采用RBCA模型计算砷、镉、铜、锌对人体健康的环境风险,结果表明,该场地砷超过了致癌风险指数标准限值-6(10)及非致癌危害商标准限值(1),说明砷具有很大的环境风险;采用IEUBK模型计算铅对人体的健康风险,结果表明,铅也具有一定的环境风险。因此,该污染场地在开发利用过程中需要对环境风险区域进行治理修复后才能使用。 相似文献
910.
BORIS PORFIRIEV 《Environmental management》1997,21(2):147-157
/ Despite the suspension and closing down of many pollutingindustrial facilities and corresponding expectations of positive change inthat field, it is argued that the environmental situation in Russia in thefirst half of the 1990s has not improved. To corroborate this point, thelatest available data are presented and the deep roots and complexities ofthe current socioeconomic and political situation in the country areanalyzed. Using analogies and "component accounting" approaches,the original economic assessments of environmental damage in the recent pastand current period in Russia are offered for comparison with similar datafrom a selection of developed countries. A model of a new environmentalstrategy and policy is developed and its economic, legal, and organizationaldimensions are examined.KEY WORDS: Damage; Environmental costs; Policy; Pollution; Publicparticipation; Risk; Strategy 相似文献