川南地区某硫铁矿废渣堆周边农田土壤重金属污染水平及源解析

为探究硫铁矿区废渣堆对周边农田造成的影响，系统采集了川南某硫铁矿废渣堆及周边农用地土壤样品共61件，测定其重金属（Cr、Ni、Cu、Zn、Cd、Pb、As、Hg）的含量，分析8种重金属污染水平及空间分布特征，利用相关性和主成分分析对重金属进行源解析，并借助综合生态风险指数、地累积指数等方法评估土壤污染风险水平．结果显示，研究区土壤中Cr、Cu和Cd含量超过国家相应标准，且Cr、Cd、Pb和As的含量明显高于土壤背景值，分别为背景值的1.56、1.40、1.45、2.89倍；Ni、Cu和Zn含量的空间分布相对均匀，而其它5种重金属的空间分布相对集中；矿区周边农田土壤整体处于中等生态风险水平（150

Evaluation and source analysis of heavy metal pollution in farmland soil around a pyrite slag heap in Southern Sichuan Province

To explore the impact of pyrite slag heap on surrounding farmland, 61 soil samples were systematically collected from a pyrite slag heap and surrounding agricultural land in Southern Sichuan Province, and the contents of heavy metals (Cr, Ni, Cu, Zn, Cd, Pb, As, Hg) were determined, and the pollution levels and characteristics of the spatial distribution of eight heavy metals were analyzed. The sources of heavy metals were identified by correlation and principal component analysis, and the risk level of soil pollution was evaluated by a comprehensive ecological risk index and geo accumulation index. In the soil, the results showed that the contents of Cr, Cu and Cd of the study area exceeded the corresponding national standards, and the contents of Cr, Cd, Pb, and As were significantly higher than the background values, which were 1.56, 1.40, 1.45 and 2.89 times of the background values, respectively. The spatial distribution of Ni, Cu and Zn content was relatively uniform, while the spatial distribution of the other five heavy metals was relatively concentrated. The farmland soil around the mining area was at a medium ecological risk level (150