Pollution Characteristic and Ecological Risk Assessment of Heavy Metals in Superficial Sediments of Hongfeng Lake

Concentrations,distribution and accumulation of heavy metals in the sediments of Hongfeng Lake were investigated.The highest values for heavy metals concentrations in sediments before the modern industrialization of the world and the environmental background values of Hongfeng Lake were used to analyze the accumulation coefficient and potential ecological risk(PER) coefficients for heavy metal.The PER index for each sample location was also discussed.The method for evaluating PER index presented by Lars Hkanson was applied to assess the ecological risk.The distribution of various heavy metal contents reveals the regional distributive characteristics,and the concentrations are higher in the north part of the lake than those in the south part.When the highest values for heavy metals concentrations in sediments before the modern industrialization of the world were taken as references,the accumulating order for these heavy metals is: Cd(Hg)(As)CuZnPb,and the order of pollution level is: CdHgAsCuPbZn.When the environmental background values of Hongfeng Lake worked as references,the accumulating order is: CuCdZnAsPbHg,and the order of pollution level is: CdHgAsCuPbZn.