Study on the ecological characteristics of phytoplankton community in Minjiang Estuary

Investigations on phytoplankton community and environmental factors were carried out in Minjiang Estuary of Fujian,in May(spring) and November(autumn) of 2009.There were in total 129 species in 54 genera found out in this sea area,of which 118 species in 46 genera were Bacillariophyta,accounting for 91% of all species;8 species in 5 genera were Pyrrophyta,accounting for 6%;1 species in 1 genus was Cyanophyta,accounting for 1%;1 species in 1 genus was Chlorophyta,accounting for 1%;1 species in 1 genus was Cryptophyta,accounting for 1%.The dominant species in spring were Skeletonema costatum,Chaetoceros curvisetus and Chaetoceros debilis;and the dominant species in autumn were Skeletonema costatum,Coscinodiscus subtilis and Coscinodiscus jonesianus.The cell abundance of phytoplankton ranged from 1.56×103 to 7.43×105 cell/L.The abundance of phytoplankton was significantly correlative to the water temperature and chlorophyll-a concentration in spring.However,there were significant negative correlation of phytoplankton abundance to salinity,and positive correlations of phytoplankton abundance to DIN concentration in autumn.