Analyses on water quality and its protection in East Lake Taihu

根据2002年4月至2003年4月东太湖的水质监测结果,分析了东太湖的水质现状、空间分布特征及变化趋势．其中TN变化范围0.57-3.91mg/L,平均值1.61 mg/L,NH4+-N变化范围0.01-0.42mg/L,平均值0.14mg/L,NO3--N 变化范围0.044-0.549mg/L,平均值0．16mg/L,而TP平均值为0.103mg/L,与以前的调查结果相比,TN、TP和NH4+-N 均明显增加,CODMn有所下降,水质状况总体较差,但不同水域因其影响因子不同,水质亦有明显差别,湖心区水质最好．目前,东太湖水体总体上处于中富营养状态,部分湖区已达到富营养状态．最后根据东太湖水环境的现状,提出一些措施和建议．;Based on the water quality investigation in East Lake Taihu from April 2002 to April 2003, a preliminary analysis was carried out on the water quality, its changes and the spatial difference in given districts. The mean value of the water quality parameters ranged as follows: TN, 0.57-3.91 mg/L with a mean value of 1.61 mg/L; NH4+-N, 0.01-0.42 mg/L (0.14 mg/L on the average); N03--N, 0.044-0.549 mg/L, (0.16 mg/L on the average); and the mean TP was 0. 103 mg/L. Compared with the results of earlier investigations, TN, TP and NH4+-N had increased, CODMnhad slightly decreased . At present, the water quality was bad, but different sites exhibited different conditions. The water quality in the center of lake was the best. As a whole, East Lake Taihu was meso-eutrophic. Some part of the lake was eutrophic. To improve the water quality of East Lake Taihu, it is important to shut off the external pollution sources, ensure the function of East Lake Taihu, control the scale of pen-culture and recover and protect the aquatic vegetation.