A study of metal contamination in sediments in Beisan River System
北三河水系沉积物中金属的污染状况研究

Beisan River System consists of Wenyu River, Liangshui River, Beiyun River, etc., which receives most wastewater discharge from Beijing and Tianjin.The contamination of metals in sediment of the rivers is an important parameter for evaluating the quality of water environment.In this study, the levels and speciation of metals in sediment from Beisan River System were investigated and the pollution class was evaluated with the CSST sediment quality guideline and geo-accumulation index.The sources of the metals were estimated with correlation analysis and principal component analysis.The results showed the average concentration of Fe, Mn, Zn, Cr, Cu, Ni, Pb, Co and Cd was 24207, 538, 303, 57, 48, 29, 15.2, 14 and 0.27 mg·kg-1, respectively.The pollution class of metals in sediments from Niumutun River was the highest in the 8 rivers investigated.In the sediments investigated, Fe, Cr, Ni, Cu, Mn and Zn mainly existed in residual fraction, with the ratio of 92.5%, 85.2%, 87.9%, 71.0%, 63.4% and 57.3%, respectively.Pb mainly existed in the extractable fraction with the ratio of 62.6%.Cu, Pb, Ni and Cd in the sediments were mainly influenced by anthropogenic factor and the distribution of these elements was mainly controlled by the content of total organic carbon.In comparison, Cr and Co were mainly influenced by natural factor and the distribution was mainly controlled by Fe and Mn oxides or clay mineral.