渭河(陕西段)表层沉积物重金属污染现状及其潜在风险研究

Heavy Metal Pollution Status and Potential Ecological Risk in Surface Sediments of Wei River,Shaanxi

基于实测数据分析渭河陕西段表层沉积物Hg、As、Se、Sb、Cu、Zn、Pb、Cd、Cr、Ni、Mn、V、Co和Tl 14种重金属的污染现状及其潜在生态风险。结果表明:表层沉积物受到多种重金属的复合污染,除Sb和Tl外,其余12种重金属的平均含量超过其土壤背景值;依据地质累积指数(I_(geo))和潜在生态风险指数(RI)评价,表层沉积物重金属的综合潜在生态风险介于轻微生态危害和极强生态危害之间,Hg和Cd污染最为严重,是该区域优先防控的重金属。

The pollution status of 14 heavy metals including Hg,As,Se,Sb,Cu,Zn,Pb,Cd,Cr,Ni,Mn,V,Co and Tl in surface sediments of Wei River in Shaanxi section were analyzed and the potential ecological risks of the heavy metals were evaluated. The results indicated that the surface sediments were contaminated by various heavy metals,and the average contents of the heavy metals,except Sb and Tl,were above the corresponding soil background values for Shaanxi. According to the geo-accumulation index（ I（geo）） and the potential ecological risk indexes（ RI）,the comprehensive ecological risks of 14 heavy metals were between the moderate ecological hazards and the strong ecological hazards. Hg and Cd were the most polluted heavy metals in the sediments,which showed the largest contribution to RI. Thus,Hg and Cd were as the priority controlled heavy metals in the areas.