Evaluation of Heavy Metal Pollution in Main Rivers of Kunming

The contents of As, Pb, Cd, Cr, Cu and Zn in the sediments of five main rivers in the main urban area of Kunming from 2014 to 2019 were analyzed and evaluated by Pollution Load Index method, Index of geo-accumulation method and Potential ecological risk method. The results of Pollution Load Index analysis showed that the average CF_i of heavy metals ranged from 1.68 to 52.36, and the contribution of seven indexes to pollution was as follows; Cd>Hg>Zn>Cu>Pb>As>Cr; The PLI values of the five rivers ranged from 3.02 to 18.88, and the pollution levels were extremely strong. The order of pollution load was: Yunliang River > Chuanfang River > Xin River > Daqing River >Panlong River. The analysis results of Index of geo-accumulation showed that the accumulation of heavy metals in the Yunliang River and Chuanfang River in the five rivers was much higher than that in the other three rivers, and the overall pollution order of each index was: Hg>Cd>Zn>Cu>Pb>Cr>As. The results of Potential ecological risk analysis showed that the average value of heavy metals in sediments of five rivers ranged from 3.36 to 1570.64, and the order of heavy metal hazards was: Cd>Hg>Cu>Pb>As>Zn>Cr; RI values ranged from 1074.61 to 9157.91, and the potential ecological hazards of the five rivers were very strong. The order of the degree of risk was Yunliang River > Chuanfang River > Daqing River > Xin River > Panlong River.