基于改进重叠投影法的空间耦合水污染评估模型

为准确评估库区上游河流突发水污染的危害程度,针对库区上游区域河床中上游窄、下游宽的结构特点,在传统重叠投影法的基础上,于重叠区域上边界引入流速、水位、污染物浓度等物理量的二次横向分布函数,基于神经网络的思想,采用最速下降法构建训练算法,对各分布函数中的未知参数进行训练,将收敛后的分布函数作为模型的连接条件,进而建立改进的一维、二维水动力和水质空间耦合模型;以青龙河流域为例,将训练得到的分布函数的必要参数作为一维、二维连接,模拟了河流环境中污染物的时空变化规律。结果表明,改进的耦合模型计算结果稳定,显著降低了物理量由一维向二维过渡时的突变性,相比传统重叠投影的单数值传递,改进的方法以训练后的分布函数作为一维、二维耦合的连接,可以大幅度提高耦合的精确性。

水环境信息系统的技术体系

本文在实践的基础上,总结和分析了水环境信息系统的内容体系以及结构体系,将水污染经济损失评估模型引入到水环境信息系统中,结合水环境数据库,可进行区域水污染经济损失核算,从而丰富和发展了水环境信息系统的内容。

Assessment of Groundwater Pollution Potential through GIS Technique： A Case Study for Pelly-Mianrudan Plain, Lali Urban District, Iran

Considering the low average rainfall in the country and the importance of groundwater as a water supply source for drinking and agricultural water sections, water quality condition of groundwater must be controlled and prevented from any contamination. Identifying the vulnerable areas to pollution is one way of prevention. Many models have been offered for this purpose. In this study, a numerical rating scheme, called DRASTIC has been used for evaluating potential for groundwater pollution in pelly-mianrudan plain that is located in northern Lalli city in Khuzestan province. Resulted map obtained in GIS environment shows that the study area has DRASTIC index of 71-150 that is divided to five vulnerable zones namely no significance, very low, low, low to moderate, moderate to high. Maximum groundwater vulnerability correspondent low to medium zone that approximately covers 45 percentage of the study area and other parts on the northwest and center of the study area has high vulnerability. The sensitivity analysis showed that correlation DRASTIC index with net Recharge （0.68） and Impact of vadose zone media （0.63） parameters is more than other parameters in the study pelly-mianrudan area. The statistical analysis confirms that parameter soil media and topography are the most sensitive to contamination, followed in importance by parameters aquifer medium, vadose zone, recharge, hydraulic conductivity and depth to water.

Impact of Wastewaters on the Physico-Chemical Quality of Waters： Case Study of the Rhumel River, Hammam Grouz and Beni Haroun Dams

The primary objective of this study is to evaluate the physico-chemical qualities and the organic pollution of two dams--Hammam Grouz and Beni-Haroun, as well as that of Rhumel river. The latter, which feeds the dams is an important water source in the geographical region of the Constantinois. The presence of the stations of filtration and purification has not been sufficient to minimize the effect of the waste discharges released from various agglomerations. Five site points were selected in strategic locations where samples have been collected monthly during 2009. Multiple physico-chemical assessments have been conducted. The parameters determined have revealed that the quality of waters for the two dams is fair. The level of organic pollution is more pronounced in the waters of Hammam Grouz dam compared to that of Beni Haroun. This may be attributed to animal debris--very important organic content, which is a characteristic of the peripheral waters of the first dam （Hammam Grouz）. On the other hand, the waters of the Rhumel river were assessed of mediocre quality, reflecting the presence of organic pollution.

Assessment of the Total Organic Carbon and Conductivity in Consecutive Dyeings with Reactive Dyestuffs Using Treated Effluent by UV/H202 Photocatalysis

The paper was monitored the conductivity （g.L＂l of NaCI）, the absorbances values （Abs） and the amount of TOC （total organic carbon）, before and after five consecutive dyeings made with reuse water, obtained from treated effluent by UV/H202 photocatalysis. All rates of decolorization were above 92%, the removal of total organic carbon was above 89% in all treatments and the economy of NaCI was from 3.10 in the first recipe, 3.17 in the second, 3.49 in the third, 3.79 in the fourth and 4.05 in the fifth recipe. The five dyeings compared with same dyeings made with deionized water presented a color deviation （AE＊） below 1. The conventional dyeings would consume 80 L/kg against 40 L/kg used in the dyeing process proposed in this study, representing a great economy of water, with no discharge of effluents.

城市水环境整治方案研究——以苏北某市老城区为例

本研究以苏北某市老城区为研究区域,分析其水环境相关的各种时空因素,利用量化的动态模型对研究区市政排水风险、水污染负荷进行评估,发现现状排水能力未达到1年一遇,河道污染负荷均大于水环境容量。在量化计算和分析的基础上,制定了以规划管控、截流调蓄、净化处理、生态修复等工程与非工程措施相结合的城市水环境整治思路,为老城区水环境整治提供基础,并为其他类似城市水环境治理提供借鉴。

Health Risks Assessment Due to Exposure to Vinyl Chloride in Groundwater from a Closed Landfill： A Case Study as a Contaminant of Concern and Effect of Subsurface Characteristics

The purpose of this study was to analyze the migration pathways of contaminants from closed landfills and to estimate health risks based on soil characteristics. The health risks were estimated using Framework for Risk Analysis Multimedia Environmental Systems （FRAMES） software. The sensitivity of human health risks and hazard indices due to vinyl chloride contamination in groundwater were performed in relation to soil characteristics such as Darcy velocity, thickness of soil layer, mass of contaminant present in the aquifer. Based on the analysis, Darcy velocity showed no effect on estimated risks. Since soil layer thickness had a significant effect on the estimated health risks, effects of different soil types on estimated risks were analyzed. The results showed that soils from the least appropriate to the most appropriate for risk management due to groundwater contamination were sand, sandy clay, sandy loam, loam and clay loam. FRAMES model was suitable for assessing the health risks due to vinyl chloride contamination in groundwater originating from a municipal solid waste landfill. The model showed the changes in both carcinogenic and non carcinogenic risks over time. The estimated health risks were directly correlated with the levels of vinyl chloride detected in groundwater.

Application of biomonitoring and support vector machine in water quality assessment

The behavior of schools of zebrafish （Danio rerio） was studied in acute toxicity environments. Behavioral features were extracted and a method for water quality assessment using support vector machine （SVM） was de- veloped. The behavioral parameters of fish were recorded and analyzed during one hour in an environment of a 24-h half-lethal concentration （LC50） of a pollutant. The data were used to develop a method to evaluate water quality, so as 6＋ 2＋ to give an early indication of toxicity. Four kinds of metal ions （Cu2~, Hg2~, Cr , and Cd ） were used for toxicity testing. To enhance the efficiency and accuracy of assessment, a method combining SVM and a genetic algorithm （GA） was used. The results showed that the average prediction accuracy of the method was over 80% and the time cost was acceptable. The method gave satisfactory results for a variety of metal pollutants, demonstrating that this is an effective approach to the classification of water quality.

Terahertz-dependent PM2.5 monitoring and grading in the atmosphere

Rapid industrialization and economic development have led to serious pollution in the form of fine particulate matter(PM2.5,particulate matter with a diameter of less than 2.5 μm). In China, PM2.5 has been one of the most debated topics in councils of government and issues of public concern. Terahertz(THz) radiation was employed to measure the PM2.5 in the atmosphere from September 2014 to April 2015 in Beijing. Comparison of the PM2.5 level from the website with THz absorbance revealed a significant phenomenon: THz radiation can be used to monitor PM2.5 in the atmosphere. During Asia-Pacific Economic Cooperation(APEC) 2014, "APEC Blue" was also recorded in a THz system. The relationship between absorbance and PM2.5 demonstrates that THz radiation is an effective selection for air pollution grading. Based on the absorbance spectra, the elemental compositions were studied by two-dimensional correlation spectroscopy(2 DCOS) in conjunction with X-ray fluorescence.Several single absorption peaks were revealed and caused by sulphate from coal combustion, vehicle exhaust emissions and secondary reactions. Furthermore, mathematical algorithms, such as the BPANN and SVM, can process the THz absorbance data and greatly improve the precision of the estimation of PM2.5 mass. Our results suggest that THz spectroscopy can not only reveal the component information for pollution source determination, but quantitatively monitor the PM2.5 content for pollution level evaluation. Therefore, the use of THz radiation is a new method for future air pollution monitoring and grading systems.

Risk Assessment of Metal Contamination in Soil and Groundwater in Asia： A Review of Recent Trends as well as Existing Environmental Laws and Regulations

Asia is experiencing a more rapid economic growth compared to any other regions. The contamination of soil and groundwater with metals can mainly be attributed to human activities; therefore, risk assessments to characterize the nature and magnitude of risks to humans and ecological receptors from contaminants are important. Risk assessments are often iterative processes, which involve identification and filling data gap. Experimental samplings, geostatistical and multivariate statistical methods as well as multimedia risk assessment modeling are the three major methodologies used in the assessment of metal contamination in soil and groundwater.This review highlights a number of measurements for improving risk calculation methods and expounds scientific approaches that involve the identification of the major source of contamination, exposure pathways and bioavailability of metals. In general, risk assessments of metals in soil and groundwater worldwide are mainly focused on the levels of contamination, identification of exposure pathways, and prediction of the probability of contamination. To date, very limited studies have reported the development of relevant environmental laws and policies in the regulation of soil and groundwater contamination in Asia. The development, variations and limitations in the regulations of soil and groundwater contamination among developed countries may provide helpful guidance for the developing countries in Asia.