Phytoplankton Community Structure and Biological Assessment in Mangshe River

In order to investigate the status of phytoplankton community and water ecological environment of Mangshe River in Yancheng city,six sites were settled to monitor the species composition and community structure of phytoplankton in spring and autumn during 2012 to 2013. Diversity index was used to evaluate the water ecological status. The assessment results indicated that there were 64 taxa of phytoplankton were identified,with diatoms,chlorophyta and cyanophyta as the dominant species. The phytoplankton density in autumn was significantly higher than in spring. Succession and cross of dominant phytoplankton species were existent. A fair-good phytoplankton diversity level was showed,and indicated a light pollution of Mangshe River. Shannon-wiener diversity index,Margalef species richness index and Pielou evenness index values in spring appeared higher than in autumn,and the difference between upstream and downstream sites was insignificant.