北京某金矿区土壤重金属污染特征及风险评价  

Pollution characteristics and risk assessment of soil heavy metals in a certain gold mine area in Beijing

作　　者：韩娟娟[1] 吴大鹏 张涛 HAN Juanjuan;WU Dapeng;ZHANG tao(Geological Engineering Design and Research Institute,Beijing 101500,China)

机构地区：[1]北京市地质工程设计研究院,北京101500

出　　处：《城市地质》2021年第4期424-431,共8页Urban Geology

基　　金：北京市矿山地质环境监测系统建设(二期)项目(PXM2017_158303_000003)。

摘　　要：使用网格布点法采集144个浅层土壤样品,分析测定As、Cd、Cr、Cu、Hg、Ni、Pb和Zn共8种重金属元素的含量。通过多元统计方法、土壤重金属含量空间分布及极值点分析,揭示了金矿地区土壤污染特征及污染风险。结果显示,区内浅层土壤重金属含量超过该地区背景值较高的元素为Pb、As、Cd,与背景值接近的元素为Cr与Ni。重金属污染风险较高的区域集中分布在金矿开采区、尾矿库、选矿厂及其下游约1.5 km范围内,主要污染元素为As、Cd、Pb、Cu、Zn,基本不存在Cr、Ni、Hg污染。相关性与主成分分析结果显示,矿山开采及冶炼是土壤重金属污染的主要来源。污染物的主要迁移途径为金矿开采区、尾矿库及选矿厂的废渣和尾矿析出的重金属通过废渣及尾矿堆的孔隙下渗进入底垫土壤,通过地表径流进入下游土壤中。One hundred and forty-four surface soil samples were collected by grid distribution point method,and the contents of As,Cd,Cr,Cu,Hg,Ni,Pb and Zn were tested.The characteristics and risks of soil heavy metal pollution in the study area were revealed using multivariate analysis,spatial distribution analysis and extremum analysis.The results showed that:the concentration of Pb,As and Cd exceeded the Pinggu background values,while the concentration of Cr and Ni approached the background values.The areas with high risks of heavy metal pollution were concentrated in the gold mining area,tailings dams,mineral processing plant and its downstream within about a 1.5-kilometer radius.The main pollution elements were As,Cd,Pb,Cu and Zn,and there was basically no Cr,Ni and Hg pollution.Correlation and principal component analysis of heavy metal pollution showed that the pollution of soil heavy metals in the gold mine area came mainly from mining and smelting.The main migration route of pollutants in the study area was as follows:heavy metals from slag heap and tailings in the gold mining area,tailings dams and mineral processing plant infiltrated into the underlying soil and entered the downstream soil through surface runoff.

关 键 词：金矿 重金属 污染特征 风险评价 

分 类 号：X53[环境科学与工程—环境工程] X820.4