贡嘎山东坡土壤重金属质量比的初步分析及风险评价  

Preliminary analysis and risk evaluation of heavy metals in soil from eastern slope of Gongga Mountain

作　　者：曹洋[1] 张丹[1] 李伟[1] 李同阳[1] 刘明德[1] 王可琴[1] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所,山地表生过程与生态调控重点实验室,成都610041

出　　处：《安全与环境学报》2012年第1期154-160,共7页Journal of Safety and Environment

基　　金：国家自然科学基金项目(40871111)

摘　　要：对贡嘎山东坡土壤中Cd、Pb、Cr、Ni、Hg和As的质量比进行测定,用单因子污染指数法和内梅罗综合污染指数法对其进行风险评价。结果表明:研究区表层土壤中Hg、Pb和As质量比低于国家一级标准,属未污染等级,Cd、Cr和Ni质量比存在不同程度的超标现象,土壤被污染;Cd、Pb、Cr、Ni、Hg、As的单因子污染指数分别为1.88、0.87、1.15、1.06、0.45、0.26,对土壤的污染程度从大到小依次为Cd、Cr、Ni、Pb、Hg、As;内梅罗综合污染指数PN为0.92～4.89,都属于不安全级别,其中22.2%的土壤属尚清洁等级,66.7%的土壤属轻度污染,11.1%的土壤属严重污染。The present paper is aimed at reporting our collection and determining the concentrations of Cd,Pb,Cr,Ni,Hg and As in soils of the eastern slope of Gongga Mountain.The results of our collection and analysis show that the mean concentrations of six heavy metals in top soil are CrNiPbAs CdHg in degraded order.The mean concentrations of Pb,Hg and As in the top soil prove to be below the tolerance limit（grade-1 in accordance with the state standard established for testing the uncontaminated soils）,though lead was found different from the mean concentrations about（30.38±7.32） mg/kg dw in the topsoil from the eastern slope of the Mountain,that is,very close to the tolerance limit.At the three sampling points of the surface layer in the Faber＇s matured-fir forest, lead concentrations tends to be over the tolerance limit（43.1 mg/kg dw,41.8 mg/kg dw,35.7 mg/kg dw）,and so are the mean concentrations of Cd,Cr and Ni（grade-1 in accordance with the standard set up by the state）.The variation coefficient of Cd is maximal at 0.91,whereas that of Pb—minimal at 0.24.Of all the three different forest types,mean concentrations of Cd,Pb,Hg and As in the surface layer of the Faber＇s matured-fir forest turns to be higher than the Faber＇s Fir/Purdom Poplar（Populus purdomii） mixed forest and the Faber＇s middleaged fir forest.Thus,we have found that there were significant variations with Pb,Hg and As concentrations,but not with Cd.In the mean time,the average concentrations of Cr and Ni in surface layer of the Faber＇s Fir/Purdom Poplar mixed forest were significantly higher than those in the other two.Thus,it can be concluded that the distribution of heavy metals determined in soil layers at each of the three points surveyed proves to be diversified,though the degree of variation turns to be not very obvious with the mobility of Cd,Cr,As,and Hg in the soil horizon from the top-layer to deep-layer.Besides,we have also worked out the single-factor contaminant index data by analyzing the information obtained

关 键 词：土壤学 重金属 评价 贡嘎山东坡 

分 类 号：X53[环境科学与工程—环境工程]