Studies and Demonstration Engineering on Ecological Restoration Technique in the Littoral Zone of Lake Dianchi:the Target and Feasibility

作为滇池沿岸带生态修复技术研究及工程示范系列研究论文之一,主要分析研究了滇池东北部沿岸带原有生态状况、现有环境基础、实施局部岸段生态修复的有限目标、实现这一目标的主要限制性环境因子及其可控性.结果显示,滇池东北部沿岸带入湖河流密集,发育良好的湖滩湿地原本是拦截净化入湖河水的生态屏障;湖滩湿地被围垦之后,人工岸堤前风浪侵蚀强烈,水生植物和水生动物消失,但沙质沉积物淤积形成了次生浅滩;在次生沙滩上创建挺水植被,仍然可以发挥沉积掩埋污染物、捕获分解漂浮性蓝藻的污染控制功效;实施生态修复所面临的限制性环境因子主要为风浪的强烈冲刷和水质严重污染,这些因素都可以通过相应的环境改造与控制措施加以解决,因而实现生态修复目标是可能的.;As part of the series studies on ecological restoration technique in the littoral zone of Lake Dianchi, this paper investigated the primary wetland environment and vegetation in the northeastern bank littoral zone of Lake Dianchi, the present environmental bases, the target and feasibility for ecological restoration, the key limiting environmental (actors and their controllability. It resulted that, there were four inflow rivers in the research area which took large amount of soil into the lake and formed 4 km² wetland in the littoral zone. The reed-vegetated wetland worked as an ecological barrier to keep the lake from pollution. When the concrete dike was built up, the wetland was made into paddy field and fish pond. In front of the dike the aquatic plants and animals, and even the soil were washed out by strong wind waves. Only sand from the nearby rivers was moved here and formed a sand beach, witch was growing up at the rate of 20mm/a. For the effect of both wind waves and water pollution, no any plant growing on the sand beach. It's possible, feasible and reasonable to establish new wetland vegetation on the sand beach in front of the dike. The key limiting factors, both wind waves and water pollution were controllable. It was confirmed lhat the new wetland vegetation could be established, stabilized and will work for pollution control.