Ecological restoration of shallow, eutrophic lakes-experimental studies on the recovery of aquatic vegetation in Wuli Lake

Abstract

依据浅型湖泊生态系统的多稳定态理论,在富营养湖泊治理过程中,当外来污染得到有效控制时,通过人工重建水生植被可以加速湖泊的生态恢复。在五里湖中,挺水植物和浮叶植物都能很好地生长,水底光照不足是沉水植物难以生长的主要原因。在自然条件下建成了永久性挺水植物群落和浮叶植物群落,在人工控制的围隔环境中改善了水底光照条件,建成了沉水植物群落。但这些沉水植物仍不能渡过夏季,主要原因是湖水过深和水温较高,降低水位和建造人工浅滩可为五里湖沉水植被恢复创造有利条件。本研究可为富营养水体的水质控制和植被恢复提供多种实用技术,但在水生植被的结构与环境功能等方面仍需开展深入的定量研究。;According to the theory of multiple stable states of shallow lake ecosystems, it is possible to speed the ecological restoration process by recovering aquatic vegetation in eutrophic lakes. In Wuli Lake, both emerged plant and floating-leaved plant could adapt to the eutrophic habitat, but submerged plant was limited by low light intensity at the lake bottom. Permanent e-merged plant community and floating-leaved plant community was built under natural conditions of Wuli Lake, and some submerged plant communities were set up in the enclosures where the water quality was improved and the underwater light intensity increased. The submerged plant community could not survive the summer for the high water temperature and high water level in the season. To make the habitat in Wuli Lake suitable to submerged plants one possible way is to control the water level and build shallow littoral zone by moving the fertile mud from the center area to the littoral zone. In the present studies, some usable techniques have been mastered for water quality control and aquatic vegetation recovery in shallow eutrophic lakes, and more detailed quantitative studies were needed on the relationship of structure and environmental function of aquatic vegetation.