ABSTRACT
Objective To explore the characteristics and ecological risk assessment of heavy metals pollution in the fluvial sediment in Hengyang section of Xiang river.Methods The fluvial sediments in 18 sites in 10 sections of Hengyang section of Xiang river were collected for determination of heavy metals(Cu,Zn,As,Hg,Cd,Cr,Pb) in 2007.The accumulation levels of heavy metals in the fluvial sediment and their potential ecological risks were assessed by the Hankanson potential ecological risk(PER) factors method.Results The average potential ecological risk index of Cd in sediment of Xiang river was 352.1 with the highest ecological risk,the index of Hg was 272.1 with higher ecological risk,the index of Pb and As was 150.1 and 104.7 with high ecological risk,the index of Cr,Zn and Cu were all lower than 40 with low ecological risk.On the whole,the integrated pollution index of seven kinds of heavy metal was 913.4.Conclusion The fluvial sediment of Hengyang section of Xiang rive has been polluted by heavy metals in a certain degree and is characterized as a complex pollution situation with a higher ecological risk.