Abstract:

Standing stock and productivity of phytoplankton and their cell size structure and the relations with environmental factors in Prydz Bay and the adjacent waters of the Indian sector of the Southern Ocean were observed during summer of 1990/1991.The results showed that there were obvious spatial zonation of above parameters in the studied area. In Prydz Bay and the adjacent shelf chlorophyll, cell abundance, POC and primary productivity were high, which resulted from higher stability of water masses. In offshore beyond the continental shelf between West Ice Shelf and Shackleton Ice Shelf, biomass and productivity of phytoplankton and POC were also high, due to the mixing depth being shallower than euphotic depth.On the contrary,the opposite distribution trends of above parameters were displayed in both east and west zone of the studied area. The results of size-fractionation showed that the contributions of nanoplankton with picoplankton to total phytoplankton biomass was 53%,to total productivity,69%, which proved their importance in phytoplankton community of the Antarctic waters.