Investigation on River Pollution and Potential Ecological Risk Assessment in Industrial Area:Taking Dalangwo River as an Example

The water quality and heavy metal in sediment of Dalangwo River in industrial area,Sanshui,Foshan,were investigated and analyzed.Hakanson potential ecological risk index was employed for analysis of the ecological risk of Dalangwo River sediment.It indicated that the content of COD,ammonia nitrogen,TP,DO and Cr in Dalangwo River did not reach classⅤcriterion of surface water environment.The average concentration of Cu,Zn and Cd in sediment did not meet class Ⅲ criterion for soil evaluation.The sediment dredging out from Dalangwo River could not be directly used in farmland as fertilizer because the average concentration of Cu,Zn and Pb exceed the controlled standards for pollutants in sludge for agricultural use.The results from potential ecological risk index method demonstrated that the potential ecological hazard of heavy metal had strong negatively effect on Dalangwo River sediment.And the average degree of potential ecological harm was established as the following ranking:CdCuPbZnCr.