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在太湖一湖湾的物理-生态工程围区内，采用覆膜和改变生态位的越冬技术，使喜早莲子草、风眼莲等漂浮植物能安全越冬，并有效地改善水体透明度，为沉水植物生长及种群自我演替提供了保障。静态试验结果表明，采取简易的防寒越冬技术，改变生态位的喜早莲子草对ＴＮ、ＮＨ_４~＋－Ｎ、Ｃｈｌａ的去除率达７７．２％、９０．１％、５８．３％，透明度提高１．５倍：对喜早莲子草覆膜并间种沉水植物，这一镶嵌组合群落对ＴＮ、ＮＨ_４＋－Ｎ、Ｃｈｌａ的去除率达６５．７％、９０．７％、５８．７％，透明度提高１．６倍。动态试验结果表明，当富营养化湖水在围区内滞留时间达７．３３ｄ时，经越各处理的镶嵌组合群落使围区内水体透明度达９０～１００ｃｍ，比围区外提高２．６－３．０倍，对ＴＮ、ＴＰ及ＮＨ_４＋－Ｎ的浓度分别比围区外降低３７．５％、５２．０％及７５．４％；而滞留时间低于４．３３ｄ时，净化效果不明显。
In the physical-ecological engineering enclosure of a lake in Taihu Lake, overwintering technology that mulches and alters ecological niche will make winter plants such as Hydrangea xylostella and Aegilops colchicus safely wintering and effectively improve the transparency of water, Water plant growth and population self-succession provides a guarantee. The results of static tests showed that the removal rates of TN, NH_4 ~ + -N and Chla for the modified niche of A. xylostella were 77.2%, 90.1% and 58.3%, respectively, with the simple cold-overwintering technique. 1.5 times higher than the control: the rate of removal of TN, NH 4 + -N, Chla was 65.7%, 90.7%, 58.7 %, Transparency increased by 1.6 times. The dynamic test results show that when the eutrophication lakes in the Wai residence time up to 7.33d, through the mosaic of the combination of community to make the waters within the watershed transparency of 90 ~ 100cm, outside the area increased by 2.6 - 3.0 times. The concentrations of TN, TP and NH_4 + -N decreased by 37.5%, 52.0% and 75.4% respectively than those in the surrounding area. When the residence time was less than 4.33d, the purification effect was not obvious .