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461.
Francisco Ferreira Hugo Tente Pedro Torres Sérgio Cardoso José M. Palma-Oliveira 《Environmental monitoring and assessment》2000,65(1-2):443-450
The environmental decision-making process is related with the interpretation of data both in spatial and temporal dimensions. This paper presents a methodology that integrates the time-space framework of air quality data to infer the temporal pattern and spatial variability that could be interpreted for environmental decision purposes. Variograms that accommodate time and space lags were used for the analysis and proved to be effective. Its environmental meaning, in particular its relationship with traffic patterns is discussed. Data from air quality monitoring stations located in the central part of Lisbon were used in this study. It describes a strategy to identify the type of vehicles responsible for certain pollutant levels, particularly for nitrogen oxides, and discusses the application of new air quality European legislation to the city of Lisbon, Portugal. 相似文献
462.
用蚕豆根尖细胞微核技术检测乌鲁木齐河水质 总被引:2,自引:0,他引:2
应用蚕豆根尖细胞微核技术对乌鲁木齐水质进行检测,测定各样点水样诱导的蚕豆根尖微核千分率及综合污染指数,并进行F检验,结果表明,各样点MCN‰有显著性差异,20个样点中有11个样点 的综合污染指数大于2,4个样点水样的综合污染指数大于3.5,和对照组相比有显著差异。所获得数据表明乌鲁木齐河水质受到较为了严重的致突变性污染。 相似文献
463.
简要介绍了纸片法测定水质总大肠菌群的操作方法,并通过6个实验室的验证试验,研究了纸片法与现行标准方法(多管法)的一致性。结果表明,2种方法的测定结果基本一致,无显著性差异,但纸片法测定周期比多管法缩短了2d,仅需1d即可。 相似文献
464.
Stef Proost 《Integrated Assessment》2000,1(2):145-156
This paper surveys some recent studies on conventional air pollution and climate change in the transport sector in Europe.
Fuel efficiency standards, car emission standards and transport pricing instruments are analysed from an economic perspective
taking into account environmental and economic efficiency objectives.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
465.
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467.
伊犁河伊宁市段水质污染特征分析 总被引:3,自引:1,他引:2
在对伊犁河伊宁市段历年水质状况进行综合评价的基础上,探讨了城市河段水质的变化规律、污染特征和成因。 相似文献
468.
Modelling vegetation greenness responses to climate variability in a Mediterranean terrestrial ecosystem 总被引:2,自引:0,他引:2
Accurate knowledge of the quality and environmental impact of the highway runoff in Pear River Delta, South China is required
to assess this important non-point pollution source. This paper presents the quality characterization and environmental impact
assessment of rainfall runoff from highways in urban and rural area of Guangzhou, the largest city of Pear River Delta over
1 year’s investigation. Multiple regression and Pearson correlation analysis were used to determine influence of the rainfall
characteristics on water quality and correlations among the constituents in highway runoff. The results and analysis indicates
that the runoff water is nearly neutral with low biodegradability. Oil and grease (O&G), suspended solids (SS) and heavy metals
are the dominant pollutants in contrast to the low level of nutrient constituents in runoff. Quality of highway runoff at
rural site is better than that of at urban site for most constituents. Depth and antecedent dry period are the main rainfall
factors influencing quality of highway runoff. The correlation patterns among constituents in highway runoff at urban site
are consistent with their dominant phases in water. Strong correlations (r ≥ 0.80) are found among chemical oxygen demand (COD), total phosphorus, Cu and Zn as well as conductivity, nitrate nitrogen
and total nitrogen. O&G, COD, SS and Pb in highway runoff at urban site substantially exceed their concentrations in receiving
water of Pear River. The soil directly discharged by highway runoff at rural site has contaminated seriously by heavy metals
in surface layer accompanying with pH conversion from original acidic to alkaline at present. 相似文献
469.
The analysis of three years of 8-h CO concentration values registered in a deep street canyon downtown shows high frequency of values that exceed WHO health protection guidelines. An inverse relationship between opposing percentiles of the distributions of CO concentrations and mean wind speed could be found. Data also showed a variation of mean CO values with prevailing wind direction. The averaged concentration value obtained when the sampler probe is on the leeward side is lower than the obtained when it is on the windward wall. A preliminary explanation of this feature may be related to the advection of polluted air from a high traffic density area nearby. 相似文献
470.
Thomas F. Cuffney Michael R. Meador Stephen D. Porter Martin E. Gurtz 《Environmental monitoring and assessment》2000,64(1):259-270
The condition of 25 stream sites in the Yakima River Basin, Washington, were assessed by the U.S. Geological Survey's National Water-Quality Assessment Program. Multimetric condition indices were developed and used to rank sites on the basis of physical, chemical, and biological characteristics. These indices showed that sites in the Cascades and Eastern Cascades ecoregions were largely unimpaired. In contrast, all but two sites in the Columbia Basin ecoregion were impaired, some severely. Agriculture (nutrients and pesticides) was the primary factor associated with impairment and all impaired sites were characterized by multiple indicators of impairment. All indices of biological condition (fish, invertebrates, and algae) declined as agricultural intensity increased. The response exhibited by invertebrates and algae suggested a threshold response with conditions declining precipitously at relatively low levels of agricultural intensity and little response at moderate to high levels of agricultural intensity. This pattern of response suggests that the success of mitigation will vary depending upon where on the response curve the mitigation is undertaken. Because the form of the community condition response is critical to effective water-quality management, the National Water-Quality Assessment Program is conducting studies to examine the response of biota to gradients of land-use intensity and the relevance of these responses to water-quality management. These land-use gradient pilot studies will be conducted in several urban areas starting in 1999. 相似文献