Investigation and Analysis of Phytoplankton in Yuanxinhu Area of Changhu Lake in Spring

In order to reveal the characteristic of phytoplankton community structure and assess the water quality in spring in Yuanxinhu,area of Changhu Lake in Hubei Province,a survey was carried out about phytoplankton in Yuanxinhu,Changhu Lake in the spring of 2012.And according to the species composition of phytoplankton,as well as the level of biomass and dominant were integrated to assess the nutrient degree of water body.Results showed that 80 species of phytoplankton were identified,among which Chlorophyta accounted for 45.0%,followed by Bacillariophyta(30.0%)and Cyanophyta(10.0%).The biomass of phytoplankton ranged from3.48~6.69mg/L with the average of 4.44mg/L.Sampling points use Chlorophyta and Bacillariophyta as the dominant,total number of species were 39.50%and 36.10%respectively,and a similar pro-portion in more than 30%.As a result,the water quality of Yuanxinhu,Changhu Lake was in a mesotrophic state.