[Community structure of phytoplankton and its relationships with environmental factors in drinking water source of Jinshu Bay, Taihu Lake].

By using canonical correspondence analysis (CCA),this paper studied the community structure of phytoplankton and its relationships with environmental factors in the drinking water source of Jinshu Bay,Taihu Lake.A total of 7 phylum and 58 genera were identified,and the phytoplankton community was dominated by Cyanophyta,Bacillariophyta,and Chlorophyta.The quantity of phytoplankton was slightly higher in summer (250×104 ind·L-1) than in spring (238×104 ind·L-1),but the community structure differed obviously between the two seasons.In spring,Cyanophyta was the dominant phylum,and Anabaena was the dominant genus;in summer,Chlorophyta was the dominant phylum,with no dominant genus but abundant quantity of Merismopedia and Scenedesmus.Besides temperature,the main environmental factors affecting the distribution of phytoplankton in spring were ammonium-nitrogen,total phosphorus,total nitrogen,and phosphate,while those in summer were total nitrogen,ammonium-nitrogen,phosphate,suspended solids,macrophytes,total phosphorus,and transparency.