浙江省某尾矿库周边农田土壤重金属污染特征及来源解析  

Pollution characteristics and source identification of heavy metals in farmland soils around a tailing pond in Zhejiang Province

作　　者：吕玉娟 王秋月 孙雪梅 张志伟 张毅敏 高月香 LÜYujuan;WANG Qiuyue;SUN Xuemei;ZHANG Zhiwei;ZHANG Yimin;GAO Yuexiang(Nanjing Institute of Environmental Science,Ministry of Ecology and Environment;College of Environment,Hohai University)

机构地区：[1]生态环境部南京环境科学研究所 [2]河海大学环境学院

出　　处：《环境工程技术学报》2023年第4期1464-1475,共12页Journal of Environmental Engineering Technology

基　　金：国家自然科学基金项目(72174127,42107098);中央高校建设世界一流大学(学科)和特色发展引导专项(B22017010204)。

摘　　要：尾矿库周边生态环境安全受到高度关注,土壤重金属污染是农田治理和保护的风险源之一。以地处浙东丘陵山地的浙江省某铜矿尾矿库周边农田为研究对象,测定了农田土壤中8种重金属元素Cd、Hg、As、Pb、Zn、Cu、Cr、Ni的浓度,运用地累积指数法、污染指数法、潜在生态风险指数法和生态风险预警指数法对农田土壤重金属污染程度以及生态风险进行评价,结合正定矩阵受体模型(PMF),定量解析农田土壤重金属的来源。结果表明:1)研究区农田土壤中Cd、Hg、Cu、Zn浓度分别是土壤元素背景值的5.36、2.06、8.19、5.36倍,具有高度变异性;污染指数评价结果表明,Cu、Zn、Cd重度污染占比均达到10.5%,中度污染占比为5.26%,靠近尾矿库(<300 m)的15.8%的点位处于重度污染等级;地累积指数评价结果表明,Cd、Cu、Zn和Hg可能具有累积风险。2)潜在生态风险评价结果表明,Cd为很强生态风险,Hg为较强生态风险,Cu为中等生态风险,其余重金属均为轻微风险;综合潜在生态风险指数(RI)为308.91,综合潜在风险为较强风险。生态风险预警评估结果表明,Cu为重警,Cd和Zn为中警,Hg为轻警,As为预警,Pb、Cr和Ni为无警;综合生态风险预警指数(IER)为16.06,综合生态风险预警为重警。RI和IER空间分布基本一致,主要受Cd、Cu、Zn和Hg的影响。3)PMF解析出3个源,Cd、Zn、Cu主要受铜矿尾矿库尾砂和坝下渗水的混合源影响,贡献率分别为94.4%、94.3%和67.1%;Hg可能是以肥料、农药施用等农业活动源为主,贡献率为61.5%;Cr、Ni、Pb和As主要受成土母质和交通运输活动混合源的影响,贡献率分别为89.7%、82.7%、75.0%和68.3%。The safety of the ecological environment around tailing ponds has received high attention,and soil heavy metal pollution is one of the risk sources of cultivated land management and protection.The concentrations of eight heavy metals Cd,Hg,As,Pb,Zn,Cu,Cr and Ni were measured in the soil of a copper mine tailing pond in Zhejiang Province,which was located in the hilly mountainous area of east Zhejiang Province,and the degree of soil heavy metal pollution and ecological risk around the tailing pond were evaluated by using the geo-accumulation index method,pollution index method,potential ecological risk index method and ecological risk warning index method.The sources of heavy metals in farmland soils were quantitatively analyzed by combining the positive definite matrix factor(PMF)receptor model.The results showed that:1)The concentrations of Cd,Hg,Cu and Zn with a character of high variability in farmland soils in the study area were 5.36,2.06,8.19 and 5.36 times higher than the background values of soil elements,respectively.The pollution index showed that the percentage of heavy pollution of Cu,Zn and Cd all reached 10.5%,the percentage of moderate pollution was 5.26%,and 15.8%of the points near the tailing pond(<300 m)were in the severe pollution level.The geo-accumulation index indicated that Cd,Cu,Zn and Hg might have cumulative risks.2)The results of the ecological risk index showed that Cd was with high potential ecological risk,Hg was with considerable potential ecological risk,Cu was with moderate ecological risk and the remaining heavy metals were minor risk.The comprehensive potential ecological risk index(RI)was 308.91,which belonged to high risk level.The results of the ecological risk warning index indicated Cu was severe warning,Cd and Zn were medium warning,Hg was mild warning,As was early warning,Pb,Cr and Ni were no warnings.The comprehensive ecological risk warning index(IER)was 16.06,which belonged to severe warning level.The spatial distribution patterns of RI and IER were similar,and Cd,Cu,Z

关 键 词：尾矿库 土壤重金属 污染评价 潜在生态风险 正定矩阵受体模型(PMF) 源解析 

分 类 号：X53[环境科学与工程—环境工程]