玄武湖蓝藻水华应急治理成效分析

2005年9-10月间，以粘土法为主，对玄武湖蓝藻水华进行了应急治理。经监测表明，应急治理有效抑制了蓝藻水华，湖区景观明显改善。形成蓝藻水华的微囊藻，各湖区下降幅度大于95％。综合污染指数、富营养化程度均有不同程度的降低，水体透明度提高0．14m，水质化学耗氧量、高锰酸盐指数、总磷浓度大幅降低，但生态补水主要流经区域pH无明显改善，各湖区总氮超标率有所上升。浮游植物数量下降93％，浮游动物种群数量上升47％，底栖动物种类数量无显著变化。相对静止水域细菌总数持平，生态补水流经区域细菌总数下降幅度较大。治理期间未发现大型水生植物、鱼虾批量死亡。沉积物中，铜、铅、砷含量无明显差异，汞含量升高，但低于往年监测水平，有机质略有升高，总磷含量有较大幅度上升。

Analysis of Emergency Control Effectiveness of Blue -green Alge in Xnanwu Lake

The modified clay was applied to control the blue - green alga bloom occured in Xuanwu lake from Sept. to Oct. in 2005. The quantity of Microcystis cells decreased 95% through the contral manipulation. The comprehensive pollution index and eutrophication level decreased. The SD increased about 0.14 m and the concentrations of COD, CODMn, and TP all decreased. But in the main areas of ecological supplement water, the amount of phyloplankton decreased 93% and the populations of zooplankton rose 47%. In the areas of ecological supplement water, the organic matter and TP all increased by a big margin.