摘要
沉积物释放是海洋环境中甲烷(CH4)的重要来源。通过2013年7月和8月两个航次,对东、黄海泥质区沉积物中CH4浓度的垂直分布和沉积物-水界面通量进行了研究。结果表明,除个别站位外,黄海沉积物(50cm以浅)中CH4的浓度变化范围在0.2~1.0μmol/L之间,长江口及浙闽沿岸附近的沉积物中CH4浓度则要更高(1.0~2.0μmol/L),而东海东部海域沉积物中CH4浓度波动范围为0.2~3.0μmol/L。总体来说,东、黄海沉积物中CH4浓度偏低,这可能与观测到的高浓度硫酸盐(>20mmol/L)有关。通过整柱密室培养实验估算出东、黄海沉积物-水界面CH4释放速率在0.64~2.12μmol/(m^2·d)之间,东、黄海沉积物CH4释放总量为6.7×10^8mol/yr;但采用菲克定律估算的CH4扩散通量则要比现场培养的结果低2~5倍,表明不同的方法在估算沉积物-水界面CH4通量上还具有一定的不确定性。
Sedimentary release is an important source of marine and atmospheric CH4.of CH4 concentrations in the sediment cores in the East China Sea and the Yellow Sea were determined to investigate its vertical profiles and sediment-water CH4 fluxes.CH4 concentrations in the Yellow Sea sediments ranged from 0.2μmol/L to 1.0μmol/L(depth<50 cm)except for station L06 under 40 cm(22.0μmol/L).CH4 concentrations in the sediments in the Changjiang River Estuary and the adjacent areas ranged from 1.0μmol/L to 2.0μmol/L.In the eastern area of the East China Sea,CH4 concentrations in the sediments varied greatly,ranging from 0.2μmol/L to 3.0μmol/L.In general,low CH4 concentrations observed in the study areas may relate to the high concentration of sulfate(>20 mmol/L).We estimated the sediment-water CH4 fluxes as 0.64~2.12μmol/(m2·d)by conducting the intact core incubation experiments.Our results combined with the previous studies indicated that the sediment-to-water CH4 emission in the East China Sea and the Yellow Sea was estimated as 6.7×108 mol/a.However,the emission rates estimated by Fick's law were 2~5 times lower than that calculated by the incubation experiments,suggesting the uncertainties when estimating the sediment-water CH4 fluxes due to different models.
作者
叶旺旺
谷雪霁
康绪明
刘素美
张桂玲
YE Wang-wang;GU Xue-ji;KANG Xu-ming;LIU Su-mei;ZHANG Gui-ling(College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China;Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education,Ocean University of China,Qingdao 266100,China;Yellow Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Qingdao 266071,China)
出处
《海洋科学》
CAS
北大核心
2019年第7期77-86,共10页
Marine Sciences
基金
科技部重点研发计划(2016YFA0601302)
国家自然科学基金(41521064)
泰山学者工程专项
“鳌山人才”计划(2015ASTP-OS08)~~
