Comparative Studies on Community Structure, Biodiversity of Plankton and Zoobenthos in Four Lakes of Different Trophic States in China

摘要

Studies were conducted in four shallow Chinese lakes of different trophic states in Liangzihu water system Results indicated that species number was negatively correlated with degree of water eutrophication, and lakes of similar trophic condition hadhigher similarity of species. The most significant differences of species composition were observed in rotifers and zoobenthos. The density and biomass of phytoplankton, protozoans, rotifers, oligochaetes and chironomids tend to increase with increasingnutrients. Percentage contribution of each algal class to total density and biomass of phytoplankton in lakes of different trophic states was calculated. A significant difference in dominant species was found in different waters, especially the eutrophicor hypereutrophic lakes were dominated by a few species of oligochaetes. The abundance of Tanypus chinensis Wang showed a highly significant correlation with the degree of eutrophication. Highly eutrophic lakes had significantly lower diversity in rotiters and zoobenthos.