西藏尼洋河流域表层沉积物重金属污染特征分析

Heavy Metal Pollution of the Surface Sediments in Niyang River,Tibet

  • 摘要: 对西藏尼洋河沉积物中Cu、Zn、Cd、Pb、Cr 5种重金属元素的含量进行了分析测定,采用富集系数、变异系数法和潜在生态危害指数评估了其污染程度。结果表明:除Cd以外,其他重金属元素含量均低于西藏土壤背景值;重金属元素除Cd外的富集系数均<1.5 (其他高于1.5者多为5号采样断面);潜在生态风险因子均低于40,潜在生态危害指数大多低于70。尼洋河尚未出现重金属污染,具有低的生态风险,但该流域重金属Cd的人为排放确实存在。

     

    Abstract: Heavy metal pollution in the sediment is an important factor affecting river ecosystem. The surface sediments were collected from Niyang River to study the pollution of five kinds of heavy metals,namely Cu,Zn,Cd,Pb,Cr. The results showed that except for Cd,the most of heavy metal contents were lower than the soil background values. Enrichment factor( EF) values revealed that Cd,Cu,Zn,Pb and Cr in the whole were less than 1. 5; and the orders of the average Eri for the studied metals were less than 40. The mean RI values showed less than 70. Heavy metal pollution has not occurred in Niyang River and has low ecological risk,but the anthropogenic emissions of heavy metal Cd in this basin do exist.

     

/

返回文章
返回