Current Assessment on Heavy Metal Pollution in the Sediment of Le’an River

According to the concentration of heavy metals in each sampling site in 2003,methods of composite pollution index,index of geoaccumulation and potentional ecological risk index were used to evaluate heavy metal pollution.Results indicated that Le’an River has been polluted by heavy metals seriously,with the order of heavy metals,from highest to lowest pollution degree with Igeo value as Cu PbZn for the upriver;the same state in the middle of the river;Pb Zn Cu for the downriver.The distribution of pollutants in the River sediments were divided into three sections with different ecological risk characteristics on the whole,lower ecological risk area in headstream;single metal high ecological risk area and multi-metal high ecological risk area.Three methods can reflect the same change trend along the River,although there were some difference,they could complement each other.