生态治理工程对太湖入湖河道水环境改善效果的研究

Effects of Ecological Restoration Engineering on Improving Water Environment of Lake-influent River in Taihu

梅梁湾是太湖北部污染程度最为严重地区之一,对其杨湾段入湖河道及河口区域,通过生态清淤干化、构建前置库、围隔工程与植被恢复等生态修复综合手段进行生态治理。治理期间,分别于2010年5、7和9月对该示范区域进行水质和生物调查监测。结果显示,工程后期水体透明度平均值达到了48 cm,TN和TP的去除率分别达到12.7%～88.2%和30.3%～95.8%;浮游植物优势种的变化表明,水体的富营养化程度降低;Shannon指数和Pielou指数的变化也指示了水体健康水平逐渐提升。生态治理使杨湾水质得到改善,水生态系统得到修复。

Meiliang Bay is one of the most serious pollution areas in the northern part of Taihu Lake. Ecological dredging, pre-reservoir technology, control alage in lake level and ecological restorations with revegetation were carried out in Yangwan River of Meiliang Bay, in order to improve the water quality. In this study, we collected water and phytoplankton samples in May, July and September 2010 individually to estimate the water quality. The transparency of water body increased to 48 cm in later period of the engineering, and the removal ratio of TN and TP was 12.7% - 88.2% and 30.3% - 95.8% respectively. Changes of the dominant species of phytoplankton indicated a lower water entro- phic state. Both the Shannon and Pielou biodiversity index of phytoplankton showed that the water ecosystem health is getting better. Both wa- ter quality and the ecosystem of Yangwan River are improving after construction of wetland restoration engineering.