郑州市郊区土壤重金属污染评价分析

为揭示城市化过程对土壤环境质量的影响,本研究以郑州市郊区为例,对其表层土壤重金属Pb、Cr、Cd、Hg、As含量进行了测定分析,按照单因子污染指数法和内梅罗综合污染指数法,根据土壤环境背景值标准进行了评价,并应用克里格插值方法对研究区内表层土壤污染的空间变异特征进行了分析。结果表明,研究区表层土壤中各种重金属均有超过背景值现象;其中Cr含量远远高于背景值,重度污染,为主要污染因子,Pb为轻污染,其它重金属处于警戒线等级;污染综合指数均超过1,处于轻污染以上等级;各重金属单因子污染指数和综合污染指数在郑州市郊区的分布特点各不相同。

Soil Heavy Metals Pollution Assessment in the Suburb of Zhengzhou City

To investigate the influences of urbanization process on soil environment, the study was conducted in the suburb of Zhengzhou city. The concentrations of heavy metals Cd, Hg, Pb, As and Cr in the topsoils were analysis, and the soil environmental quality on the base of the environmental background value criteria were evaluated by single factor index and Nemerow multi-factor index method, respectively. Furthermore, the spatial variability of soil pollution in terms of heavy metals was researched with the Kriging interpolation method. The results indicate that the average contents of heavy metals(Cr and Pb) in the soil exceed the background values, in which, the concentrations of Cr was higher than background value, suggesting that Cr might be considered as a dominant element causing soil heavy metal pollution in the study area; Pb was in slightly polluted, while other heavy metals were not in polluted states; and the integrated contamination index of all sample have exceed 1, being in polluted grades; Regional differences of index of soil heavy metal were very notable.