城市表层土壤重金属污染多元统计分析和污染评价

Multivariate Statistical Analysis of Heavy Metals Contamination in Urban Topsoil and Pollution Assessment

分析了某城市不同功能区土壤中重金属As、Cd、Cr、Cu、Hg、Ni、Pb、Zn含量的319个空间样本,结果表明:重金属As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的含量均超过了城区背景值,尤以Hg、Cu、Zn、Cd含量超标最严重。运用因子分析方法得出As、Cr、Cu、Ni来自工业区,Cd、Pb、Zn来自交通区,Hg来自公园绿地区的农药。最后采用内梅罗指数污染评价方法得出各功能区重金属污染程度从重到轻依次为工业区、交通区、生活区、公园绿地区和山区。

319 space samples about the contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in the soil of different functional zones in some cities were analyzed, the results showed that the contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were heavier than that of the background values, especially for the contents of Hg, Cu, Zn and Cd. Factor analysis was applied to identify sources of these metals, it indicated that the concentrations of As, Cr, Cu and Ni were mainly associated with industrial regions, while that of Cd, Pb and Zn were mainly from traffic zone. Additionally, that of Hg was primarily originated from pesticide in the park. The Nemerow integrated pollution index （NIPI） for the eight heavy metals shows that the rank of the pollution from heavy to light was ： industrial zone, traffic area, residential area, green area in the parks and mountainous area.