某工矿废弃地重金属污染评价及农田复垦修复建议

以四川某废弃硫磺矿厂区域为研究区,采集78个土壤样本,测定土壤Cd、Cr、Cu、Ni含量及p H值。采用单因子污染指数、内梅罗综合污染指数评价研究区重金属污染程度,采用聚类分析解析污染来源,GIS制图呈现污染空间分布。以土壤环境质量二级标准值为参考,单因子污染指数评价结果显示,重金属样本点位超标率由高到底依次为Cd(84.6%,表层)Cu(53.9%,表层)Ni(51.3%,表层)Cr(32.3%,次表层);内梅罗综合污染指数评价结果表明研究区属于中度污染级别;聚类分析结果表明研究区重金属Cr、Cu、Ni污染来源于矿渣,Cd污染来源尚不明确;GIS制图结果表明污染程度较重的区域主要分布在研究区西南侧。本调查评价旨在为土壤污染治理方案的制定提供参考。

Assessment of Heavy Metal Pollution for an Abandoned Mine Area and Suggestions on Farmland Reclamation

This paper takes an abandoned sulfur mine in Sichuan Province, China as the study area. Totally 78 soil samples were collected, and contents of Cd, Cr, Cu and Ni were measured. The pH of the sample was also measured. Single factor and Nemerow pollution index method were used to evaluate soil pollutions. Cluster analysis method was used to explore the pollution sources, and GIS mapping was used to observe spatial distribution characteristics of the pollution. According to the standard, the single factor pollution index for each heavy metal followed are in order of Cd(84.6%, surface) > Cu(53.9%, surface) > Ni(84.6%, surface) > Cr(32.3%, subsurface).Nemerow pollution index evaluation shows that the study area is mildly polluted. Cluster analysis shows that Cr, Cu and Ni are from slag, while the source of Cd is not clear. GIS mapping results indicate that heavy metal pollution is mainly distributed in the southwest of study area.