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Human Health Risk Assessment Model of Organic Pollution in Groundwater: Shijiazhuang Industrial Zone
In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds (VOC) after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that: (1) Compared with these permissible level standards in China (GB 3838-2002) and National Primary Drinking Water Regulations of the United States, the residents’ daily life had not been affected by the groundwater in this area (except for relative bad water quality of HB3-4 and HB3-6); (2) The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; (3) As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; (4) Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents’ in study areas; (5) In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was: drinking water pathway > dermal contact pathway. 相似文献
94.
刘子诏 《地质灾害与环境保护》2011,22(2):116-120
为提高生产速度,指导生产,以饱和细粒土为实验材料,研究剪切速率的变化对样品凝聚力和摩擦角的影响. 相似文献
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国内某著名煤炭企业计划实施每年10万吨的CO2地质储存(CCS)项目,拟选了5组地层做为目标储层。但所选封存层平均渗透率在0.15~0.6mD,平均孔隙度在2~6%,属于低渗低孔地层,如不进行人工压裂提高注入层渗透率,要实现预定存储目标尚有一些困难。笔者在研究中发现,除对目标层进行一定的水裂酸化处理提高地层渗透特性可以显著提高注入性和存储能力外,CO2注入速率的变化对地层的封存能力和注入性也有明显影响。运用TOUGH2-ECO2N软件分别模拟了无水裂及水裂情况下8种不同注入速率下这些目标存储层的压力变化及CO2封存状态比例及理论最大封存能力。模拟结果表明使用水裂酸化方法对储层进行处理后,不仅可以使注入总量达到项目要求,还可使系统理论最大储存能力提高55%;并且在灌注过程中采用变速灌注方式,可以有效控制系统压力积聚,对将来实际灌注压力控制具有重要意义。 相似文献
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Marco A. Lardies José Luis Muñoz Kurt A. Paschke Francisco Bozinovic 《Marine Ecology》2011,32(1):42-51
The colonisation of the terrestrial environment by crustaceans is more apparent in tropical latitudes because of the high diversity of semi‐terrestrial and terrestrial crabs. However, in temperate regions there are also great numbers of crustaceans that inhabit ecological niches at the water–air interface. Grapsidae crabs (Decopoda) are especially important in studies of water‐to‐land transition as the family contains species occupying the intertidal and adjacent regions. A way to evaluate the ability of intertidal invertebrates to breathe air is to measure the aerial/aquatic oxygen consumption ratio. The objective of this study was to test the effect of thermal variation on the aquatic and aerial metabolism. We selected as study model the decopoda crab Cyclograpsus cinereus Dana and utilised five populations of the species spread over 2000 km along the Chilean coast. To determine the compensation capacity in respiration with respect to latitude, we evaluated metabolic rate at the same temperature in a common garden design in the laboratory, to examine the extent to which variation in crab physiology is environmentally determined. Whereas in our study, mb (body mass) varied significantly with latitude, the difference in mass‐independent metabolism both in air and water persisted, indicating that observed differences in MR (Metabolic Rate) were not an effect of differences in body size. We demonstrated that C. cinereus is able to breath oxygen from air and water as expected for an amphibious crab. Almost all the studied populations of C. cinereus show a aerial/aquatic metabolism ratio near 1. The pattern found indicates an increase in metabolic rate, both aerial and aquatic, in low latitudes and therefore does not support the latitudinal compensation hypothesis for temperate habitats. Finally, these kinds of studies are required to make the necessary link between ecological physiology and macroecology and to help develop a global understanding of organismal function in marine systems. 相似文献
99.
盐度对日本鳗鲡生长及非特异性免疫酶活性的影响 总被引:2,自引:0,他引:2
利用实验生态学和酶学方法,在浙江省海洋水产养殖研究所清江试验场研究了盐度对平均体长为25.1±5.6cm的日本鳗鲡(Anguillajaponica)生长及其血清溶茵酶(LZM)、超氧化物歧化酶(SOD)及碱性磷酸酶(AKP)活性的影响,实验持续60d.实验设置了5个盐度梯度(盐度5、10、15、20、25)和对照组(盐度0),每梯度设3个平行组,各组盐度和pH值保持一致.日本鳗鲡血清中免疫酶活力指标:碱性磷酸酶、溶茵酶、超氧化物歧化酶在实验的第7天和第14天测定.实验结果表明,盐度5组相对增重率最高(279.78%±28.37%),其次是盐度10组(278.74%±22.25%),盐度15、20、25组相对增重率分别为234.39%±21.28%、230.28%±26.31%、228.01%±29.29%.对照组相对增重率为233.20%-4-25.18%,盐度5和10组与对照组差异显著(P〈0.05),其余各组与对照组差异不显著.第7天和第14天,盐度10组碱性磷酸酶活性最高,分别为225.05U/dm。和251.11U/dm’,其次是盐度5组,分别为221.76U/dm。和236.01U/dm。,显著高于对照组(P〈0.05).第7天和第14天盐度20、25组溶菌酶活性显著高于对照组(P〈0.01).超氧化物歧化酶随着盐度的升高呈逐步上升趋势.第14天,盐度20、25纽溶菌酶活性仍保持较高水平,SOD回落至对照组水平,而各组AKP较第7天略有上升. 相似文献
100.
Formation rates of Subantarctic mode water and Antarctic intermediate water within the South Pacific 总被引:1,自引:0,他引:1
Corinne A. Hartin Rana A. FineBernadette M. Sloyan Lynne D. TalleyTeresa K. Chereskin James Happell 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(5):524-534
The formation of Subantarctic Mode Water (SAMW) and Antarctic Intermediate Water (AAIW) significantly contributes to the total uptake and storage of anthropogenic gases, such as CO2 and chlorofluorocarbons (CFCs), within the world's oceans. SAMW and AAIW formation rates in the South Pacific are quantified based on CFC-12 inventories using hydrographic data from WOCE, CLIVAR, and data collected in the austral winter of 2005. This study documents the first wintertime observations of CFC-11 and CFC-12 saturations with respect to the 2005 atmosphere in the formation region of the southeast Pacific for SAMW and AAIW. SAMW is 94% and 95% saturated for CFC-11 and CFC-12, respectively, and AAIW is 60% saturated for both CFC-11 and CFC-12. SAMW is defined from the Subantarctic Front to the equator between potential densities 26.80-27.06 kg m−3, and AAIW is defined from the Polar Front to 20°N between potential densities 27.06-27.40 kg m−3. CFC-12 inventories are 16.0×106 moles for SAMW and 8.7×106 moles for AAIW, corresponding to formation rates of 7.3±2.1 Sv for SAMW and 5.8±1.7 Sv for AAIW circulating within the South Pacific. Inter-ocean transports of SAMW from the South Pacific to the South Atlantic are estimated to be 4.4±0.6 Sv. Thus, the total formation of SAMW in the South Pacific is approximately 11.7±2.2 Sv. These formation rates represent the average formation rates over the major period of CFC input, from 1970 to 2005. The CFC-12 inventory maps provide direct evidence for two areas of formation of SAMW, one in the southeast Pacific and one in the central Pacific. Furthermore, eddies in the central Pacific containing high CFC concentrations may contribute to SAMW and to a lesser extent AAIW formation. These CFC-derived rates provide a baseline with which to compare past and future formation rates of SAMW and AAIW. 相似文献