大宝山矿区河流表层沉积物重金属污染及潜在生态风险评价

采用Hakanson潜在生态危害指数法对广东大宝山矿区4条河流的水系沉积物重金属污染进行了潜在生态风险评价.多种重金属生态风险指数RI表明:4条河流的重金属污染均达到了强生态危害,导致生态危害的主要重金属元素是Cd、Cu和As,Pb、Hg次之,Zn、Cr影响最小;主要受污染河流为矾洞河与船肚河.分析表明,采矿活动对重金属的含量及分布有很大影响,Pb-Zn、Pb-As、Zn-Cd和Zn-As的同源性很高,Hg则表现出不同于其它元素的累积特征;沉积物的粒度对重金属元素在其中的含量也有较大影响,除Cr、Hg和Pb外,Cd、Cu、As、Zn等元素在沉积物中的含量均受沉积物粒度的影响.

Heavy Metals Pollution in Stream Sediments and Potential Ecological Risk Assessment in Dabaoshan Mining Area

Based on the data of heavy metals in surficial sediments from four rivers in Daobanshan,the potential ecological risk of heavy metals is analyzed and assessed by Hakanson method of potential ecological risk indices.The results show that the stream sediments suffer serious heavy metal pollution.The ecological pollution is most caused by Cd,Cu,As,followed by Pb,Hg.then Zn and Cr.The Fandong River and Jilongpu River suffer most serious pollution.Statistical analyses show that mining activities decide the content and distribution of heavy metals,and that Pb-Zn,Pb-As,Zn-Cd,Zn-As are likely from a same source,while Hg appears different cumulating character.The content of heevy melals is decided by the gra nularity of sediments except for Cd,Hg and Pb.