A Study Of Contaminative Characteristics Of Sediments And Their Ecological Risk Assessment From Shuangqiao River Near Chaohu Lake

Rivers are a kind of important channel of municipal and industrial wastewater. As sediments in rivers contain a lot of pollutants ,they have a negative impact opon the quality of lake water ,e.g.Chaohu lake.So a study on contaminative characteristics of river sediment is important for tracking pollution resources and controlling Chaohu Lake Eutrophication.In this paper,resources, compositions and characteristics of pollutants from Shuangqiao River were systematically studied and potential ecological risk of heavy metals in sediment was evaluated. While 12 control cross sections were designed , 30 sampling points were chosen and 30 samples were collected for studying pollution of sediments.Compositions content of nutrient matter and heavy metals of sediments are analyzed,using XRD, atomic absorption method, etc. The effeciencies of total nitrogen, total phosphorus, organic matter, heavy metal, and the relationship between pollution factors were discussed.Research result shows that distribution of P, N, Cu, Pb, Cd in sediments from Shuangqiao River is very unhomogeneous, increasing of content of pollutants from upriver to downriver. Content of organic matter, total nitrogen, total phosphorus and heavy metal shows positive correlation,their order of correlation is TN>TP, Cu, Zn> Cu, Pb> Cu, Cd> Pb, Cd> Zn, Cd> Zn, Pb.The pollution level of heavy metal in sediment is Cd>Cu>Pb>Zn in turn, and they have higher potential ecological hazard.The ratio of N and P in sediment shows that river is in a state of eutrophication, organic matter is generated from terraneous tracheophyta.