Abstract:  

The ecological characteristics of phytoplankton community in the littoral zone of Lake Wuli, Lake Taihu were investigate monthly from July 2014 to June 2015 after the comprehensive treatment. A total of 196 species belonging to 8 phyla were identified. 37.76% of the phytoplankton was Chlorophyta, which contained 74 species. 29.08% was Bacillariophyta, which contained 57 species. The dominant phytoplankton contains 30 species of 8 phyla. In July, August, September and October of 2014, and June of 2015, Oscillatoria tenuis has an absolute advantage in the phytoplankton community, the dominant index ranged from 0.567 to 0.879. The averages variations of a month of phytoplankton density and biomass were 1.07×106-2.18×108 ind./L and 0.32-50.52 mg/L, respectively. The density and biomass of phytoplankton were significantly higher in summer and early fall than the rest month of the year due to the largescale proliferation of cyanobacteria. The density and biomass of phytoplankton were notably lower in zone A than in the rest zones. Pearson correlation analysis shows that the density of algae, biomass and species number are significant or notably significant correlated with turbidity(Tur), pH and temperature(T). Redundancy analysis shows that strong correlation was found between water temperature, dissolved oxygen, turbidity and phytoplankton community structure(p<0.01). Moreover, water temperature had the strongest correlation with phytoplankton community structure(r=0.898 2). The index calculated from phytoplankton species and diversity suggests that the littoral ecozone of Lake Wuli, Lake Taihu is suffering from a moderate eutrophication.