Study Of The Ecological Risks Of Water Environment In The Mainstream Area Of The Second Songhua River

In this paper, the mainstream of the Second Songhua River was chosen as the study object. The monitoring data of aquatic organism, heavy metal in sediment, organic poison and regular water quality was collected from Fengman Dam section, Jilin section and Songyuan section of the Second Songhua River. Biodiversity index, Eco-frangibility index of heavy metal and organic poison in sediment and water pollution risk index were calculated by mature method at present. Aggregative index of ecological risks was analyzed by AHP(analytic hierarchy process) to primarily assess the ecological risks of water environment in the mainstream area of the Second Songhua River.The study showed that, due to the different development directons of cities along the Second Songhua River, the potential ecological risks of regional water environment differed from each other. It mainly reflected that the major contributors of the risks were diverse. The contributor of the potential risk at Jilin section was organic poison and heavy metal in the bottom of the river and at Songyuan section was sanitary sewage. What's more, the potential ecological risk at Jilin section was distinctly higher than that of at Songyuan section.