ECOLOGICAL RISK ASSESSMENT OF HEAVY METALS IN SEDIMENTS IN LIANGTANG RIVER OF TAIHU BASIN

This paper studied and analyzed the space distribution characteristics of six heavy metals( As，Cd，Cr，Cu，Pb and Hg) in sediments from Liangtanghe River in Taihu Baisn． Correlation analysis showed that the Pb，Cd and Hg had significant positive correlation，the As and Cu also had a significant positive correlation and Cr did't have good relation with other metals． Based on SQGs benchmark，the concentration of As，Cd，Cr，Hg，Pb were between ERL and ERM，they may have certain toxicity to waters; the concentration of Cu in some sampling points were higher than the value of ERM，so Cu may have a very strong toxicity to aquatic ecosystems． Hakanson potential ecological risk index showed that the ecological risk of six heavy metals was in the descending order of Cd，Cu，As，Hg，Pb，Cr，all the sampling points were present some ecological risks and No． 5，No． 6 sampling point are under in a quarter strong ecological risk．