Water Quality Analysis And Evaluation Of Current Situation In The Riparian Of West Lake Taihu In Yixing

Riparian ecosystem is the most sensitive areas in response to human activities of Lakeecosystem. Unreasonable development and construction will in influence of structure functionand ecological health of riparian ecosystem. Nearshore waters are the most severely affectedareas. In this research, we investigated the present situation of ecological environment in theRiparian of west Lake Taihu in Yixing. In2012March and2012July, we investigated thesituation of water environment. In basis of the result of investigation, setting43sampling pointsalong lakeside and then monitoring total nitrogen, total phosphorus, soluble nitrogen, solublephosphorus, ammonia nitrogen, permanganate index, nitrous nitrogen and phosphate. Usingsingle-factor index method and Nemero index method to analysis the water quality of everypoints. Combining with the lakeside zone land-Use types and vegetation condition to study thepresent situation on ecological environment in each section., which provides scientific basis forthe improvement of water quality and ecological protection and restoration. The main contentsof the study as following.(1)Classifying Land-Use types into woodland, arable land, water and water conservancyfacilities land, residential land and other land uses in the Riparian of west Lake Taihu in Yixing.The result shows that, woodland, arable land and residential land are the most important types.Aquatic plants in lakeshore zone is in discontinuous distribution. Dominant species isphragmites communis.Overall, the northern is rare and southern area is flourish.(2) According to the monitoring result in March and July, eight indexes of water qualitynearshore show that total nitrogen, soluble nitrogen, ammonia nitrogen and nitrous nitrogen inMarch is higher than July. Total phosphorus, soluble phosphorus is July is increasd. Phosphateand permanganate index are in unsignificant change. According to the two monitoring result,except ammonia nitrogen and permanganate index meeting standards of Environmental qualitystandards for surface water class Ⅲ water standards of eight indicators. Concentrations ofother water quality indicators for all the43sampling points generally exceed water class Ⅲwater standard, and part of them exceed class Ⅴwater standards.(3)Single-factor index method shows that total nitrogen, total phosphorus, nitrous nitrogenare the main pollution factors. Nitrogen and phosphorus is the most important pollutionelements in Study area. The result of Nemero index method refers all of monitoring points arepolluted. The result of Nemero index between3.7and10.5. Five sampling points aremoderately polluted, accounting for12%sampling points. Thirty-three sampling points aresevere polluted, accounting for76%sampling points. Five sampling points are seriouslypolluted, accounting for12%sampling points.(4)Different section water quality is different in Study area. The water quality is better in Dapu port--HuangDu (36-44.6km) and NanhuangDu--Dongtang River(50.8-59.5km). Thewater quality is in poor quality in Xiaojing port-Shatang port（0-11.8km）, Shatang port-Xindu（11.8-27.9km）, Xindu-Dapu port（27.9-36km）and Huangdu-Nanhuang port（44.6-50.8km）.Integrated water quality of each monitoring point, the southernmost of the water quality is thebest area in the Riparian of west Lake Taihu in Yixing. Estuary is serious polluted than otherarea. The five estuary and surrounding areas are in serious pollution or severe pollution. Theland-Use type is closely related to the water quality in study area. Water quality is good oflarger woodland area. Water quality is in poor condition of arable land and residential landwhich has a larger proportion.