Phytoplankton composition in Dalijia Lake

The species composition of phytoplankton was investigated in Dalijia Lake in May,July,September and December 2004.Results indicate:There were 123 species of phytoplankton.The abundance of phytoplankton was 255.54×10~4 ind./L,The biomass of phytoplankton can reach 14.166mg/L.As the seasons changed,the phytoplankton changed obviously.The abundance apex of phytoplankton of 456.160×10~4 ind./L appeared in sum- mer;and the biomass apex of phytoplankton of 30.105mg/L appeared in autumn.The varia- tion of diversity index was Summer＞Autumn＞Winter＞Spring;and that of evenness index was Winter＞Summer＞Autumn＞Spring.The total potential productivity of this reservoir is 527760 kg,and 2804800 sturgeons were stored in it.