Characteristics of Phytoplankton Community Structure in Hongfeng Lake

The qualitative and quantitative analysis of phytoplankton in waters from 18 typical sampling points of Hongfeng Lake was conducted to know the water body status of Hongfeng Lake and the diversity and community structure of phytoplankton.The results showed that there were 55 species,belonging to 37 genera,23 families,1 suborder,13 orders and 8 phyla in phytoplankton.21 Chlorophta species,15 Cyanophyta species,9 Bacillariophyta species,3 Pyrrophyceae species,3 Xanthophyta species,2 Chrysophyta species,1 Euglenophyta species and Cryptophyceae species accounted for 38.2%,27.3%,16.3%,5.5%,5.5%,3.6%,1.8% and 1.8% respectively.The average quantity per litre and biomass of phytoplankton in Hongfeng Lake were 7.5×105 and 1.79mg/L.The dominance of Cyclotella sp.Chlorella vulgaris and Chroococcus sp.was 0.407,0.048 and 0.077 separately.The main dominant species in phytoplankton were changed,but the community structure of phytoplankton still was dominated by green alga,followed by blue-green algae in Hongfeng Lake.The diversity and uniformity variation of phytoplankton was 2.01～2.68 and 0.35～0.50 respectively,which indicated that the water body status in 2010 was better than in 1996.