A unique subseafloor microbiosphere in the Mariana Trench driven by episodic sedimentation  

作　　者：Jiwen Liu Da-Wei Li Xinxin He Ronghua Liu Haojin Cheng Chenglong Su Mengna Chen Yonghong Wang Zhongsheng Zhao Hanyue Xu Zhangyu Cheng Zicheng Wang Nikolai Pedentchouk David J.Lea-Smith Jonathan D.Todd Xiaoshou Liu Meixun Zhao Xiao-Hua Zhang 

机构地区：[1]Frontiers Science Center for Deep Ocean Multispheres and Earth System,and College of Marine Life Sciences,Ocean University of China,Qingdao 266003,China [2]Laboratory for Marine Ecology and Environmental Science,Laoshan Laboratory,Qingdao 266237,China [3]Institute of Evolution and Marine Biodiversity,Ocean University of China,Qingdao 266003,China [4]Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,China [5]Key Lab of Submarine Geosciences and Prospecting Techniques,Ministry of Education/College of Marine Geosciences,Ocean University of China,Qingdao 266100,China [6]Key Laboratory of Physical Oceanography,Ministry of Education/Research Vessel Centre,Ocean University of China,Qingdao 266100,China [7]School of Environmental Sciences,University of East Anglia,Norwich NR47TJ,UK [8]School of Biological Sciences,University of East Anglia,Norwich NR47TJ,UK

出　　处：《Marine Life Science & Technology》2024年第1期168-181,共14页海洋生命科学与技术（英文）

基　　金：supported by the Laoshan laboratory(LSKJ202203206);National Natural Science Foundation of China(92051115 and 42230412);the Fundamental Research Funds for the Central Universities(202172002 and 202141009);the Shandong Province Natural Science Foundation(ZR2022YQ38).

摘　　要：Hadal trenches are characterized by enhanced and infrequent high-rate episodic sedimentation events that likely introduce not only labile organic carbon and key nutrients but also new microbes that significantly alter the subseafloor microbiosphere.Currently,the role of high-rate episodic sedimentation in controlling the composition of the hadal subseafloor microbiosphere is unknown.Here,analyses of carbon isotope composition in a~750 cm long sediment core from the Challenger Deep revealed noncontinuous deposition,with anomalous ^(14)C ages likely caused by seismically driven mass transport and the funneling effect of trench geomorphology.Microbial community composition and diverse enzyme activities in the upper~27 cm differed from those at lower depths,probably due to sudden sediment deposition and differences in redox condition and organic matter availability.At lower depths,microbial population numbers,and composition remained relatively constant,except at some discrete depths with altered enzyme activity and microbial phyla abundance,possibly due to additional sudden sedimentation events of different magnitude.Evidence is provided of a unique role for high-rate episodic sedimentation events in controlling the subsurface microbiosphere in Earth’s deepest ocean floor and highlight the need to perform thorough analysis over a large depth range to characterize hadal benthic populations.Such depositional processes are likely crucial in shaping deep-water geochemical environments and thereby the deep subseafloor biosphere.

关 键 词：Hadal subseafloor Deep water sediment Mariana Trench Radiocarbon Microbial community Redox potential 

分 类 号：Q93[生物学—微生物学]