Phytoplankton Community in Coastal Waters of Qinzhou Bay in Guangxi

Phytoplankton composition,abundance,community structure,dominant species and diversity in coastal waters of Qinzhou Bay in Guangxi were investigated in each season in 2010.The results showed that a total of 79 genera and 193 species of phytoplankton were identified,belonging to six phyla.The cells abundance of phytoplankton varied from 0.49×104to 67.74×104cells/L with an average of 11.94×104cells/L.The largest component was Diatoms(the average of 10.47×104cells/L) containing 48 genera and 149 species,occupied 77.2% of species.Dinoflagellate(the average of 0.46×104cells/L) was the next most common with 17genera and 28 species,occupied 14.5% of species.Annual variations of the phytoplankton community in Qinzhou Bay showed a typical two-peak cycle,with the highest cell abundance peak appeared in Spring and Autumn,the lowest recorded in Summer and Winter.There were 10 kinds of dominant species during the investigation,common species and dominant species were euryhalinous,eurythermic and eurytopic species,There was succession of species in different seasons,nevertheless,some species revealed seasonal cross.Shannon-Wiener index peaked in Winter and minimized in Spring.