杭州小和山西蜜湖水质监测分析及对策

Analysis on water quality monitoring of West Honey Lake in Xiaoheshan area of Hangzhou and corresponding suggestions

西蜜湖地处杭州西部,由上埠河及附近山区的山水汇聚而成,再经由西蜜湖流入西部的主河流;因此,对西蜜湖水质情况的了解就相当于对杭州市西部地区水质情况的了解。随着湖四周建筑群的投入使用,湖水污染程度加剧。为此,选取西蜜湖中4个具有代表性的点位进行取样,监测其pH值、高锰酸盐指数(CODMn)、溶解氧(DO)、氨氮(NH3—N)、五日生化需氧量(BOD5)、石油类、总磷(TP)、总氮(TN)、氟化物(F-)这些指标。结果显示pH、BOD5、石油类、F-质量浓度均符合国家Ⅰ类水质标准,但NH3—N、TP质量浓度高于Ⅴ类水质的标准,由此可以得出富营养化是西蜜湖的主要问题。在此基础上,提出了相关的改进建议,以期为相关部门了解杭州市西部山区水质变化、采取改善水质措施提供参考。

West Honey Lake, located in the west of Hangzhou, is formed by Shangfu River and the water from mountains nearby and flows west into the main stream. Hence, findings of the water quality of West Honey Lake are equivalent to that of the western areas of Hangzhou. As the buildings around are constructed and put into use, the water pollution of the lake is exacerbated because of the sewage pipes of those buildings which lead to the lake. In the research, the investigators sample at four representative positions of West Honey Lake to survey the indexes of pH, permanganate index （CODMn）, dissolved oxygen （DO）, ammonia （NH3 -N）, five days biochemical oxygen demand （BOD5）,petroleum,total phosphorus （TP）, total nitrogen （T concentration all NH3-N and TP eutrophication is Lake is concisely N）, and fluoride （F ）. The results show that pH, BOD5,petroleum and F- meet with the standard of the national water quality criterion Ⅰ while the concentrations exceed the water quality standard grade V, which means that the main problem of West Honey Lake. The current condition of West Honey and intuitively presented by the results. This provides referential values for the water amelioration of the western mountain areas of Hangzhou. We also offer some specific proposals on how to make improvement.