Factors controlling the phytoplankton crops,taxonomic composition,and particulate organic carbon stocks in the Cosmonaut Sea,East Antarctica  

作　　者：Yuhong LI Jun ZHAO Dong LI Jianming PAN Jianfeng HE Ji HU Peisong YU Cai ZHANG Xufeng YANG Haifeng ZHANG Zhengbing HAN Haisheng ZHANG 

机构地区：[1]Key Laboratory of Marine Ecosystem Dynamics,Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China [2]Antarctic Great Wall Ecology National Observation and Research Station,Polar Research Institute of China,Shanghai 200136,China [3]Key Laboratory for Polar Science,Ministry of Natural Resources,Polar Research Institute of China,Shanghai 200136,China [4]College of Environmental Science and Engineering,Tongji University,Shanghai 200129,China

出　　处：《Journal of Oceanology and Limnology》2024年第6期1895-1908,共14页海洋湖沼学报（英文）

基　　金：Supported by the China’s National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(Nos.IRASCC 01-01-02,IRASCC 02-02);the Scientific Research Fund of the Second Institute of Oceanography(Nos.JG 2011,JG 2211,JG 2013,JG 1805);the National Natural Science Foundation of China(Nos.42276255,41976228,41976227);the International Cooperation Key Project of Ministry of Science and Technology(No.2022 YFE 0136500)。

摘　　要：The ecosystems in Southern Ocean(SO)are undergoing significant changes in the context of climate change.To identify environment-phytoplankton feedbacks in SO,seawater samples were collected in the Cosmonaut Sea(CS)during the 37 th China Antarctic Research Expedition(Jan.2021)(CHINARE-37)and subjected to analysis of particulate organic carbon(POC)and phytoplankton pigments.The remote sensing data,CHEMTAX community compositional modeling analysis,and physicochemical measurements were combined to explore the spatial variation of phytoplankton crops,taxonomic composition,and their environmental drivers.Historical phytoplankton community data from the area were also compared against those of this study to investigate inter-annual community differences and their potential causes.The column-integrated POC and chlorophyll-a(Chl-a)concentrations were 12.0±4.9 g/m^(2) and 73.8±50.5 mg/m^(2),respectively.The two most dominant taxa were haptophyte that are adapted to high Fe availability(Hapt-HiFe,mainly Phaeocystis antarctica)and Diatoms-A(Phaeodactylum tricornutum)that contributed to 33%±25%and 24%±14%to the total phytoplankton crops,respectively.Through cluster analysis,the study area was divided into two regions dominated by Hapt-HiFe and Diatoms-A,respectively.Spatially,Hapt-HiFe was mainly concentrated in the southwest coastal area that featured low temperatures,low salinity,and shallow euphotic zones.The coastal region southwest of the southern boundary of the Antarctic circumpolar current was experiencing a bloom of Hapt-HiFe during the study period that significantly contributed to the POC pool and Chl-a concentrations(R=0.46,P<0.01;R=0.42,P<0.01).Besides,the dominance of Hapt-HiFe in the CS suggests a high biological availability of dissolved Fe that is primarily associated with inputs from sea ice melt and upwellings.

关 键 词：Cosmonaut Sea particulate organic carbon phytoplankton crops phytoplankton taxonomic composition PIGMENT sea ice 

分 类 号：P941.61[天文地球—自然地理学] P734[生物学—水生生物学] Q178[生物学—普通生物学]