摘要：This paper selected Dahuofang Reservoir as the research area, analysed the relationship between waterquality and diversion water input, determined the right weight of each index affected the water quality basedon correlation analysis and entropy weight method. The results showed that after the diversion water input,the DO is 6739.17t, COD Mn is 1735.00t, BOD is 625.83t, NH 3 -N is12.07t, TP is 12.5t, TN is 1860.75t,coliform-group is 1.38 ×10 15 . The correlation between the indexes of DO, COD Mn , BOD, TN, coliform-groupand water quality is significant after diversion water input. The affected right weights of the amount of TN,coliform-group and NH 3 -N input are more than 0.1, the highest right weight is of TN input (0.1804), followedby coliform-group (0.1173) and NH 3 -N (0.1165); the most slight one is TP (0.0164). In terms of comprehensiveanalysis, the influence of each index of diversion water input on water quality of Dahuofang reservoir, theorder is TN>coliform-group>NH 3 -N>BOD>DO>COD Mn >TP.
