水质标识指数法在太湖渔业生态环境评价中的应用

Application of water quality identification index method in water quality evaluation of Taihu Lake

根据2009—2014年太湖整个湖区平水期和丰水期的实际监测结果,依据GB 3838-2002《地表水环境质量标准》,选取溶解氧(DO)、化学需氧量(COD_(cr))、高锰酸盐指数(COD_(Mn))、氨氯(NH_3-N)、总氮(TN)、总磷(TP)6项参数作为主要评价指标,应用水质标识指数法对太湖水环境状况分别综合水质评价。单因子水质标识指数评价结果表明,太湖主要污染因子的污染程度排列次序是:TP>TN>COD_(cr)>COD_(Mn)>NH_3-N>DO,TP、TN的超标造成太湖出现严重的富营养化问题,DO全年处于Ⅰ—Ⅱ类水质。综合水质标识指数评价结果表明:2009—2014年间,太湖丰水期水质总体优于平水期,且有继续变好的趋势,能达到水环境功能区目标要求。

According to the actual monitoring results of average water period and flood period from 2009 to 2014 and Surface Water Environmental Quality Standard （GB 3838-2002）, six parameters which were DO, COD- cr, CODMn, NH3-N, TN and TP were selected as the main index to evaluate water quality of Taihu Lake with the method of water quality identification index. Single factor quality identification index results show that the pollution degree of Taihu Lake is as follows： TP 〉 TN 〉 CODer 〉 CODMn 〉 NH3-N 〉 DO. The serious problem of excessive eutrophication was caused by TP and TN, and the water quality was I --[[ based on DO results. Comprehensive water quality identification index indicates that the water quality was better in flood period than in average water period, and the trend had continued to change for the better, with the requirements of water environment functional area could be achieved.