铅锌冶炼厂周边土壤重金属的空间分布特征研究

采用地统计学与GIS相结合的方法,分析了某铅锌冶炼厂周边土壤6种重金属(As、Cr、Zn、Cu、Pb、Fe)的含量分布、空间结构及其分布特征。结果表明:冶炼厂周边土壤重金属污染程度不同,重金属污染主要以Pb、Cr、Zn为主,其次为As、Cu、Fe;各采样点的Pb、Zn、Cr含量变异程度较大,变异系数分别为50%、36%、37%;As、Cu、Fe在各采样点之间的含量差异较小,变异系数小于20%;Pb与Zn具有较强的相关性,说明铅锌冶炼厂对周边土壤重金属有重要贡献。在空间分布上,Cu和As的块金值和基台值之比大于75%,空间相关性较弱;Zn、Fe、Pb、Cr 4种重金属的块金值和基台值之比都小于25%,空间相关性强。

Research on Spatial Distribution Characteristics of Soil Heavy Metal near Lead and Zinc Smelting Plant

The content distribution, spatial structure and distribution characteristics of 6 heavy metal elements （As, Cr, Zn, Cu, Pb and Fe） in the soil near a lead and zinc smelting plant were analyzed through the combined application of Geostatistics and Geo -graphic Information System （ GIS） .The results indicated that the soil near the lead and zinc smelting plant has been contaminated by these heavy metal elements, especially Pb, Cr and Zn.The contents of Pb, Zn and Cr in various sampling points changed greatly , and their coefficients of variation were 50%, 36%and 37%respectively;while the contents of As , Cu and Fe in different sampling points changed less , and their coefficients of variation were below 20%.There was a strong correlation between Pb content and Zn content , which stated that this lead and zinc smelting plant had an important contribution to the heavy metal pollution of surrounding soil .As for the spatial distribution of soil heavy metals , the ratios of nugget value to sill value of Cu and As were larger than 75%, showing weaker spatial correlation;while those of Zn, Fe, Pb and Cr were smaller than 25%, revealing stronger spatial correlation .