复杂污染源下采煤沉陷区土壤重金属分布及行为特征

Distribution and Behavior Characteristics of Heavy Metals in Soil from Coal Mining Subsidence Area with Complex Pollution Sources

采用数理统计学、克里金插值等方法研究安徽淮北采煤沉陷区土壤中Cu、Zn、Cd、Cr、Ni、Pb、As和Hg等元素空间分布及其行为特征。结果表明:土壤中Zn平均值是农用地土壤污染风险筛选值的1.1倍,其他元素未超过筛选值。Cu富集在工业园区南部,Zn、As富集在两河交汇处、工业园区南部,Cd、Pb和Hg富集在沉陷区西部,Cr、Ni富集在沉陷区东部、西部;土壤剖面上Cu最大值出现在80 cm处,Ni最大值在40 cm处,其他元素最大值均在20 cm处。土壤中元素迁移程度为Cu最高,Zn、Cr、Hg和As最低;土壤中Cd活化率较高,达到27.1%,易被植物吸收富集。

Mathematical statistics,Kriging interpolation and other methods were used to study the spatial distribution and behavior characteristics of element(Cu,Zn,Cd,Cr,Ni,Pb,As and Hg)in the soil from a coal mining subsidence area in Huaibei,Anhui.The results showed that the average content of Zn in soil was 1.1 times of its risk screening value for soil contamination of agricultural land,other elements did not exceed their risk screening values.Cu was concentrated in the south of the industrial park.Zn and As were enriched in the intersection of the two rivers and the south of the industrial park.Cd,Pb and Hg were concentrated in the west of the subsidence area.Cr and Ni were concentrated in the east and west of the subsidence area.On the soil profile,the maximum value of Cu appeared at a depth of 80 cm,the maximum value of Ni was at 40 cm,and the maximum values other elements were at 20 cm.The migration degree of Cu in the soil was the highest,and Zn,Cr,Hg and As were the lowest.The activation rate of Cd in soil was high,up to 27.1%,which was easy to be absorbed and enriched by plants.