Abstract:

During the austral summer 1991/1992,studies on species composition,abundance distribution and ecological group of net phytoplankton in Prydz Bay and its adjacent waters were carried out .78 taxa belonging to 26 genera and 3 phyla were identified,of which,percentage of diatoms was 87.2%,the other species 13.8%.The average cell abundance of phytoplankton was 120±173.8×10 5 cells/m 3.The area with high abundance of phytoplankton occurred in 62°S,78°～103°E,where cell abundance were 110×10 5 ～864×10 5 cells/m 3. According to clustering analysis of species composition and percent similarity of station clusters,phytoplankton community were divided into four cluster ecological groups: Corethron criophilum and Rhizosolenia alata group, Nitzschia and Synedra reinboldii group, Rhizosolenia alata and Synedra reinboldii group and Nitzschia and Chaetoceros group.Discussion on the relationship between phytoplankton and the environmental parameters and the comparisons between the results of present study and those of previous investigations were also made.