[Analysis on the key water quality factors to phytoplankton community in Wujingang Region of Taihu Lake].

Field investigations on the phytoplankton community were carried out in July 2009 and January 2010 in Wujingang Region of Taihu Lake (WRTL). Results show that there are 46 genus, 24 families and 6 phylum phytoplankton were identified in wet season, which is mainly composed of the Chlorophyta and Cyanophyta, the average phytoplankton abundance of this season is 14. 8 x 10(6) cell/L. There are 29 genus, 18 families and 5 phylum phytoplankton were found in level season, and Diatoms were the dominant category, the average phytoplankton abundance of the season is 3 113 cell/L. It shows that a remarkable discrepancy in community and density between the two seasons. The principal component analysis (PCA) and canonical correspondence analysis (CCA) were used to assess the phytoplankton community structure with regard to 8 aquatic environmental factors and their spatial distribution, which result on the key aquatic environmental quality factors show that NH4(+) -N and TN were the most extraordinary pollution factors which affect the phytoplankton community and WRTL was in extrophication level.