Shallow Lake Ecotypes And Its Ecological Restoration

In the past 20 years, lake ecological restoration practices all over the world show that it is notoriously difficult to restore clear water state with abundant submerged plants. Based on analysing abundant literature data, the thesis points that lake eutrophication needs a permanent cure, and ecological restoration is its core of this problem. Relying on National Dianchi"863"program, the thesis studies shallow lake ecotypes and how to restore shallow lakes through simulation experiment, project practice and field investigation. Through this reaseach, some conclusions and cognition are drawn as follows: (1) Simulation experiment is designed and carried out successfully, discovering mutuality and variation rule among aquatic plant and nutrient concentration of water, sediment, and sediment pore water. (2) Ecological characteristics of different lake ecotypes are studied; differences of ecological characteristics and its Index System between meadow lake and algae lake are analysed. (3) Ecological succession process of shallow lakes is divided into five stages, and shallow lakes are classed into eight ecotypes. (4) A set of Technic route of shallow lake eco-restoration is put forward, and filling technology of clean sediment is applied successfully to littoral cutbank belt eco-restoration of shallow lakes. The conclusions drawn in this study is important for guiding ecological restoration of shllow lakes.