The Pollution Character And Ecological Risk Assessment Of Shenyang Xihe Water

Xihe river is an inland river in Shenyang, Xihe river accepts the most part of industrial waste water and sewage that come from Shenyang city with a long term, the pollution of water is serious, and brings harms on the ecological environment.Based on the water and the sediment of Shenyang Xihe river, through researching,sampling and monitoring,the spatial distribution characteristics of the conventional pollutants (COD, NH3-N, TP), the heavy mental(Cu,Zn,Pb,Cd,Hg,As) and the PAHs was studied; The ecological risk assessment of heavy mental and PAHs in the sediment was learned by using the potential ecological risk index and SQGs, the harm impact that Xihe river brings on the aquatic was researched by using the method of micro-ecology biological exposure test. The results of the research indicate that:1. The concentration of COD, NH3-N in Xihe river exceeds the national surface water V (GB 3838-2002), the vary of COD's pollution degree in different periods is the June>the September>the November, the vary of NH3-N's pollution degree is June>November>September,the vary of TP's pollution degree is September>November> June; The concentration of Hg in Xihe river exceeds the national surface waer V standard (GB 3838-2002),the concentration of Cu,Zn,Pb,Cd,As in Xihe river does not exceed the national surface water V standard, the vary of Cu and Zn is June>the November>the September, the vary of Pb,Cd,As is June>September>November, the vary of Hg is September> June>November; The concentration of PAHs in Xihe river has been detected,the concentration of Bap exceeds the national surface water standard (GB 3838-2002), the vary of TPAHs is June> September>November.2. The concentration of Cu,Zn,Pb,Cd,As,Hg,Cr in Xihe sediment exceeds the background values of Liaoning province,the order of heavy metal pollution concentration is Zn>Cu>Pb>Cr>As>Cd>Hg, the enrichment degree of heavy mental in sediment is Cd>Hg>Cu>Zn>Pb>As>Cr, the accumulation index of Cd is the highest, achieves the level 6, belongs to the serious pollution, the second is Hg, it belongs to the serious pollution, Cu, Zn belongs to the middle level of pollution, Pb, As, Cr belongs to the mild level of pollution; the PAHs were detected in the sediment, the concentration of Nap and Bap was high, the sources of PAHs mainly come from the combustion of the wood and coal.3. The potential ecological risk index of heavy metal in Xihe sediment belongs to the more serious ecology pollution, the main factors were the Cd and Hg, the order of the ecological risk is Cd>Hg>Cu>Pb>As>Zn>Cr; Zn, Cu, Cd in the sediment can produce the acute toxicity effect easily;The PAHs in the sediment of Xihe were detected, may produce negative effects on the ecological system; Xihe river produces toxic impact on the aquatic organisms, inhibits the growth of the aquatic plants and kill the fish.