矿区农田土壤重金属分布特征与污染风险研究  

Distribution of Farmland Heavy Metals and Pollution Assessment in Mining Area

作　　者：庞妍[1] 同延安[1] 梁连友[1] 侯廷渝 高义民[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《农业机械学报》2014年第11期165-171,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：公益性行业(农业)科研专项资助项目(201203045)

摘　　要：对渭北旱原矿区130个农田土壤样品的Cd、Cr、Cu、Pb、Zn含量进行了测定,结果显示,Cd、Cu、Pb平均含量均高于陕西省土壤背景值,而Cr和Zn含量低于背景值。利用地统计方法得到的土壤重金属含量分布图显示,土壤各重金属含量由西向东呈下降趋势,水泥厂周边土壤重金属含量最高。相关性分析和主成分分析结果表明,5种重金属之间呈极显著正相关,说明其存在较高的同源性或复合关系。第1主成分主要由Cd构成,且主要反映了人为活动的影响,而第2主成分中的Cr所占负荷最高,体现了成土母质的作用,Cu、Pb和Zn含量受人为活动和成土母质共同影响。分别利用污染负荷指数(PLI)法和潜在生态危害指数(PER)法对研究区域土壤污染风险进行了评价,评价结果为煤矿区呈无污染或轻微到中度污染,水泥厂区土壤呈中度污染水平,单一元素污染程度由高到低依次为Cd、Pb、Cu、Cr、Zn。130 soil samples from farmlands in Weibei dry-land mining area were collected and analyzed for the content of Cd, Cr, Cu, Pb, Zn. The results indicated that the average contents of Cd, Cu, Pb were higher than those of Shaanxi Province soil background, while Cr and Zn contents were lower than those. The geostatistical analysis results suggested that the heavy metal contents decreased from west to east, and had the highest contents all around cement factory. There were significantly positive correlation among Cd, Cr, Cu, Pb and Zn. The principal component analysis was applied to estimate the sources of heavy metals. Cd in factor 1 was associated with anthropogenic activities, whereas Cr in factor 2 was mainly controlled by parent material, Cu, Pb and Zn were affected by both two factors. The quality of soils were evaluated with pollution load index （PLI） and potential ecological risk index （PER）, respectively. The results show that coal mine area was clean or slightly to moderately polluted, while the cement factory area was moderately polluted. Heavy metals in soil were ranked by pollution index as Cd, Pb, Cu, Cr, Zn.

关 键 词：矿区 农田重金属 污染负荷指数 潜在生态危害指数 

分 类 号：X825[环境科学与工程—环境工程]