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151.
152.
The thermodynamic law is one of the most widely used scientific principles. The comparability between the environmental impact of urbanization and the thermodynamic entropy was systematically analyzed. Consequently, the concept "Urban Environment Entropy" was brought forward and the "Urban Environment Entropy" model was established for urbanization environmental impact assessment in this study. The model was then utilized in a case study for the assessment of river water quality in the Pearl River Delta Economic Zone. The results indicated that the assessing results of the model are consistent to that of the equalized synthetic pollution index method. Therefore, it can be concluded that the Urban Environment Entropy model has high reliability and can be applied widely in urbanization environmental assessment research using many different environmental parameters.  相似文献   
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154.
为了进一步探讨我国酸沉降对水陆生态环境的影响以及典型地区生态系统对酸沉降的缓冲能力和临界负荷值,笔者对赣、鄂、湘3省具有代表性的土壤的SO吸附特性进行了研究。结果表明,红壤,待别是江西省的红壤,吸附SO的能力最强,最大吸附量达11.52mg/g士;其余依次为黄壤、棕红壤、黄褐壤和黄红壤,最大吸附量分别为11.14,8.83,6.86和6.53mg/g土;红色石灰壤对SO的吸附能力最弱,最大吸附量仅3.55mg/g土,只及红壤的30.8%。可以预计,就地区而言,以红壤为主的江西省是我国对酿沉降最敏感的地区之一。  相似文献   
155.
Preliminary study is carded out on the endocrine-disrupting organic chemicals of polychlorinated biphenyls( PCBs. PCB-28, 60,104, 153, 190) in hard roes of Ioaches( Misgurnus anguillicaudatas) in Weishanhu Lake, China. Results showed that the hard roes of Ioacbes collected from the areas near the influx( such as Pengkou T-PCB =0. 243μg/g) or efflux( such as Hanzhuang T-PCB = 0. 221μg/g)are characterized by higher PCB contents, about 4 times that from the central lake(T-PCB = 0.066-μg/g), suggesting great difference between their pollutions. The PCB distributions indicated that PCB congeners with more chlorine are more easily accumulated in roes of Ioachee. The microscopic characteristics reveal that the PCB contents at present cannot lead the roes of Ioaches to be abnormal.However, the roes with higher PCBs in Pengkou and Hanzhuang are obviously bigger than those with lower PCBs(T-PCBs≤0. 176μg/g)in other localities. It is suggested that PCBs have a stronger estrogenic activity on the roes of Ioaches, and the phenomenon is likely premonitory for the abnormal development of the hard roes.  相似文献   
156.
Systematic sampling and analysis were performed to investigate the dynamics and the origin of suspended particulate matter smaller than 2.5 μm in diameter (PM(2.5)), in Beijing, China from 2005 to 2008. Identifying the source of PM(2.5) was the main goal of this project, which was funded by the German Research Foundation (DFG). The concentrations of 19 elements, black carbon (BC) and the total mass in 158 weekly PM(2.5) samples were measured. The statistical evaluation of the data from factor analysis (FA) identifies four main sources responsible for PM(2.5) in Beijing: (1) a combination of long-range transport geogenic soil particles, geogenic-like particles from construction sites and the anthropogenic emissions from steel factories; (2) road traffic, industry emissions and domestic heating; (3) local re-suspended soil particles; (4) re-suspended particles from refuse disposal/landfills and uncontrolled dumped waste. Special attention has been paid to seven high concentration "episodes", which were further analyzed by FA, enrichment factor analysis (EF), elemental signatures and backward-trajectory analysis. These results suggest that long-range transport soil particles contribute much to the high concentration of PM(2.5) during dust days. This is supported by mineral analysis which showed a clear imprint of component in PM(2.5). Furthermore, the ratios of Mg/Al have been proved to be a good signature to trace back different source areas. The Pb/Ti ratio allows the distinction between periods of predominant anthropogenic and geogenic sources during high concentration episodes. Backward-trajectory analysis clearly shows the origins of these episodes, which partly corroborate the FA and EF results. This study is only a small contribution to the understanding of the meteorological and source driven dynamics of PM(2.5) concentrations.  相似文献   
157.
张焕祯  匡颖  王智丽  庞博 《环境工程》2013,(Z1):685-687,692
系统分析了中国高速工业化和城市化造成的环境工程本科人才市场的变化及其给环境工程高等教育带来的机遇和挑战,评价了环境工程高等教育状况,探讨了环境工程高等教育教学改革的方向,为指导环境工程大学生正确择业、促进环境工程高等教育的健康发展提供了依据。  相似文献   
158.
北京市主要公园土壤中铅含量及污染评价   总被引:7,自引:2,他引:7  
通过对北京市区12个典型公园的土壤取样调查,测定了表层土壤中铅的含量,并以中华人民共和国土壤环境质量标准(GB15618-1995)对污染状况进行了评价。结果表明,北京市区大部分公园存在铅污染问题。其表土的铅含量平均值为30.95mg/kg,变幅为16.20 ̄121.00mg/kg,污染指数为0.65~2.35。分析表明,一些历史悠久、客流量大、位于市中心的公园土壤的铅含量及污染指数均大大高于平均水平。  相似文献   
159.
结合工程实际采用水解酸化-SBR工艺处理制药废水,处理水量为2 000 m3/d。SBR对CODcr的处理率稳定在92.2%~95.8%间,平均为94.23%,对氨氮的去除率在82.7%~97.6%,平均去除率达到90.73%。水解酸化-SBR稳定运行后,系统出水各项指标均达到国家《污水综合排放标准》(8978-1996)二级排放标准。运行结果表明,SBR运行最佳参数为:曝气时间8小时,污泥负荷控制0.23~0.28(kg CODcr/kg MLSS.d),温度26℃~30℃。该工艺用于处理高浓度制药废水效果稳定,耐冲击负荷高。  相似文献   
160.
安徽太平湖水库饵料生物资源及其变化研究   总被引:3,自引:0,他引:3  
1992年11月至1993年8月,对太平洋水库浮游生物和底栖动物的周年调查结果表明,该库的天然饵料资源比较丰富,与8年前的资料相比,各类饵料生物的生物量均有较大幅度的增加,饵料生物的年产鱼潜力合计约为125万kg,化学分析结果显示,太平湖水库目前水质状况尚好。  相似文献   
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