Autumn Phytoplankton Diversity and Water Quality Evaluation in Shengjinhu Lake,Anhui

The composition and distribution of phytoplankton was investigated in Shengjinhu Lake in October 2006.And we analyzed spatial distribution pattern,dominant species and diversity of phytoplankton and its relation with the environmental factors.Simultaneously,the water quality was appraised by using various appraisal indexes.The results showed that there were 358 species of phytoplankton in total,belonging to 101 genera in 8 families.And the density of phytoplankton was significantly different among various sampling sites,ranging from 81.7×104 to 6 427×104 ind./L.There are 8 main phytoplankton groups including Cyanophyta,Cryptophyta,Bacillariophyta,Chlorophyta,Euglenophyta,Pyrrophyta,Xanthophyta,Chrysophyta,and among which the predominant species are Lyngbya spp.,Merismopedia spp.,Anabaenoideae spp.in Cyanophyta,Melosira spp.,Synedra spp.,Cyclotella spp.in Bacillariophyta and Scenedesmus spp.,Pediastrum spp.in Chlorophyta.According to the appraisal indexes and phytoplankton species,it was indicated that in the most part of Shengjinhu Lake,the extent of water pollution was very serious.And the whole lake was at eutrophic state.