부산대학교 도서관

The Southern Ocean is a region where play an important role in primary production and carbon absorption. Diatoms and P. antarctica are known as major groups of phytoplankton in the Southern Ocean. The pigment ratio of each community is mainly used to determine the biomass of each community and has been considered as an effective method. Since the pigment composition ratio of each community can be changed depending on environmental factors and their physiological conditions, many studies have been conducted cultureexperiments related to pigment synthesis. This study was conducted to identify the characteristics of each dominant community in the photosynthetic pigment productivities and to confirm the relationship with primary productivity and each photosynthetic pigment productivity in the Amundsen Sea, 2020. In this study, there was no relationship between primary productivity and the specific pigment productivity. No relationship was observed between primary productivity and the dominance of specific community, either. To find out characteristics on pigment turnover rates which are different from each other according to communities, correlations of each pigment turnover rate were examined. There was２ positive correlation between fucoxanthin (Fuco) turnover rate and diadinoxanthin (Diadino) turnover rate at the diatoms-dominant area. And There was positive correlation between three pigment turnover rates (Fuco turnover rate, 19'-hexanoyloxy-fucoxanthin (Hex-fuco) turnover rate, and Chl-a (Chlorophyll a) turnover rate) at the P. antarctica-dominant area. These results present different characteristics of pigment productivities of P. antarctica and diatoms. In this study, we also found Fuco was actively produced in the P. antarcticadominant area even though Fuco is a marker pigment of diatoms and not of P. antarctica. Moreover, there were positive correlations of specific carbon uptake rate with the ratio of Fuco turnover rate to Hex-fuco turnover rate (Fuco turnover rate / Hex-fuco turnover rate) and the ratio of Fuco turnover rate to Chl-a turnover rate (Fuco turnover rate / Chl-a turnover rate) in the P. antarctica-dominant area. That could mean the more P. antarcticacontributed to Fuco turnover rate than diatoms, the lower the specific carbon uptake rate was. To understand pigment production mechanism for these correlations, additional research on the potential factors and detail processes controlling the pigment production of each phytoplankton should be further conducted. The results in this study could be useful in inferring the contribution of each community to the primary production from specific characteristics of pigment productivity of each community, and furthermore, in enhancing accuracy in identifying community structure based on pigment composition ratios.