煤粮复合区土壤重金属含量特征及其污染评价

Heavy-metal Concentration and Pollution Assessment in the Topsoils of the Overlapped Area of Farmland and Coal Production

采集煤粮复合区27个表层土壤样品,测试其中8种重金属含量。结果表明:研究区土壤中Cu,Hg,Cd,Pb和Zn受到人为活动的干扰相对较强,81.5%的土壤处于安全状态,3.7%的土壤处于污染的警戒级别,14.8%的土壤污染程度处于轻度污染,Cd污染贡献率最高;Hg的均值处于中等潜在生态风险水平。土壤中重金属Cr,Pb,Cd和Zn含量较高的地方集中在中部偏东,Cu和Hg含量较高的地方集中在东部偏北,As和Ni在西部地区和西南地区含量较高,潜在生态风险主要集中在东北部、北部和西部区域。

The contents of Hg,Cd,As,Pb,Ni,Cu,Cr,and Zn in a total of 27 topsoil samples were measured.It is shown that the average values of Hg,Cr,Cu,Pb in the soil of the study area were higher than the background values.The concentrations of Cu,Hg,Cd,Pb and Zn are strongly influenced by human activities.Our results show that 81.5%of the soil is in a safe state,3.7%of the soil is in the alert level of pollution,while 14.8%of the soil is slightly polluted.Cd is the major factor that causes pollution.Hg is in the middle level of potential ecological risk.The heavy metals Cr,Pb,Cd and Zn in the soil are concentrated in the eastern and central part of the study area.The high concentrations of Cu and Hg are located in the northeastern part of the area,The high concentrations of As and Ni are found in the southwestern part of the area.Overall,potential ecological risks are mainly concentrated in the northeastern,northern and western part of the area.