Abstract:

Heavy metals are mainly carried in sediment of water body, their contents play important role on the environmental quality of the water body. The aim of this study is to control heavy metal pollution in Xianhe Lake and provide the basic information of ecosystem recovery of the water. The content and characteristics of 12 heavy metals（Fe, Mn, Pb, Cd, V, Zn, Ni, As, Se, Mo, Ba, Sb）of surface sediments from the water of Xianhe Lake were analyzed. Ecological risk index presented by Hakanson to assess the potential ecological risk of Xianhe Lake was utilized. The results showed that the water of Xianhe Lake was polluted mainly by Pb, Cd, As, Fe, Mn, Mo, V and Ba compared with the ‘environmental quality standard for soils’, and the lake perimeter of heavy metal pollution of Xianhe Lake was stronger than that of neihu. According to the correlation analysis of various heavy metals, there was a remarkable correlation between Ni-As, As-Mo, which suggested their origins were the same. There was unremarkable correlation between V-Ba, which suggested their origins were different. While the correlation between Fe, Mn and other heavy metals was weak, which indicated that Pb, Cd, V, Zn, Ni, As, Se, Mo, Ba and Sb deposited or adsorbed by Fe/Mn oxides or hydroxides was less in the investigated water body. Based on the potential ecological risk assessment results, the water of Xianhe Lake had reached a high ecological risk level, and the order of ecological risk of heavy metals in water of Xianhe Lake in the decline order was Cd>As>Pb>V>Mn>Ni>Zn.