Contents and Potential Ecological Risk of Heavy Metals in Middle and Lower Reaches of Second Songhua River

By analyzing the content of heavy metals of water substance in middle and lower reaches of Second Songhua River,the distribution characteristics of heavy metals were discussed and potential ecological risk of heavy metals in sediment was assessed by the method of potential ecological risk index.Results indicated that the content of heavy metals in water was relatively low,while that of sediment was relatively high.The concentration variation of heavy metals in waters and in sediments along the reach was the same,with the content higher in urban reach than in suburban reach.Potential ecological risk of heavy metals in sediment exhibits middle to very strong,with mercury and cadmium as priority risk.