Characteristics of vertical distributions of methane and dimethylsulphoniopropionate in the southern Yap Trench  

作　　者：Yuhuan HUANG Chengjun SUN Lina Lü Neal Xiangyu DING Liangmin YU Guipeng YANG Haibing DING 

机构地区：[1]Frontier Science Center for Deep Ocean Multispheres and Earth System,and Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,China [2]Marine Ecology and Environmental Science Laboratory,Laoshan Laboratory(Qingdao),Qingdao 266237,China [3]Marine Bioresource and Environment Research Center,the First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China [4]College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China [5]Key Laboratory of Tropical Marine Bio-resources and Ecology,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China [6]College of Agriculture and Life Sciences,Cornell University,Ithaca,NY 14853,USA

出　　处：《Journal of Oceanology and Limnology》2023年第6期2101-2116,共16页海洋湖沼学报（英文）

基　　金：Supported by the National Key Research and Development Program of China(No.2022YFC2803803);the National Natural Science Foundation of China(No.42076040);the National Basic Research Program of China(973 Program)(No.2015CB755904);the 111 Project(No.B13030)。

摘　　要：Methane(CH_(4) )and dimethylsulphoniopropionate(DMSP)are major carbon and sulfur sources for bacterioplankton in the ocean.We investigated the characteristics of CH_(4) and DMSP in the southern Yap Trench from sea surface to hadal zone in June 2017.We found that concentrations of CH_(4) varied from 1.5 to 4.5 nmol/L with saturation between 94% and 204% in the euphotic layer.Concentrations of dissolved DMSP(DMSPd)ranged from 0.5 to 3.7 nmol/L with higher values in surface water and decreased with depth.Concentrations of particulate DMSP(DMSPp)varied from 0 to 13.6 nmol/L.Concentrations of total DMSP(DMSPt)ranged 2.0-15.2 nmol/L.Their concentrations decreased slightly and reached consistent levels in 200-3000-m depth due probably to heterotrophic bacterial production in marine aphotic and high-pressure environments.An exception occurred around 4000-m depth where their concentrations increased considerably and then decreased in deeper water.This previously unrecognized phenomenon sheds light on the elevated concentrations of DMSP in the abyssal layer that might be affected by the Lower Circumpolar Deep Water(LCPW).Concentrations of CH_(4) in seawater of the Benthic Boundary Layer of the southern Yap Trench were slightly higher than those in the water column at approximate depth,and concentrations of DMSP in seawater of the Benthic Boundary Layer of the southern Yap Trench were not much higher than those in the water column at the approximate depth,indicating that sediment was a weak source of CH_(4) but was not a source of DMSP for seawater in the study area.This study presented clear correlations between CH_(4) and DMSP from sea surface to sea bottom,proving that DMSP might be a potential substrate for CH_(4) not only in oxic surface seawater but also in deep water.

关 键 词：METHANE dimethylsulphoniopropionate(DMSP) hadal zone Jiaolong submersible Yap Trench oceanic methane paradox 

分 类 号：P736.4[天文地球—海洋地质]