Characterization of Fe-S minerals influenced by buried ancient woods in the intertidal zone,East China Sea  

作　　者：YUAN LinXi SUN LiGuang FORTIN Danielle WANG YuHong WU ZiJun YIN XueBin 

机构地区：[1]Institute of Polar Environment, University of Science and Technology of China, Hefei 230026, China [2]Department of Earth Sciences, University of Ottawa, Ontario, K1N 6N5, Canada [3]National Institute of Health, Bethesda, Maryland 20892, USA [4]Advanced Lab for Environmental Research and Technology (ALERT), USTC-City U Joint Advanced Research Center, Suzhou 215123, China

出　　处：《Chinese Science Bulletin》2009年第11期1931-1940,共10页

基　　金：Supported by the Project of the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KZCX3-SW-151)

摘　　要：An ancient wood layer dated at about 5600 cal. a BP by AMS14C dating was discovered in the intertidal zone, East China Sea. Samples affected by ancient woods, including fresh coast bedrock, weathering bedrock, seepage water from coast, seepage water from ancient wood layer, intertidal seawater, fresh water, beach mud, ancient wood barks and ancient peat, were collected for geochemical analysis. The beach mud and the bacteriogenic iron oxides (BIOS) in coastal seepage water were analyzed by min-eralogical and high-resolution transmission electron microscopy (HRTEM)-selected area electron dif-fraction (SAED) analysis. Inorganic sulfur compositions and δ34S of the ancient peat and the beach mud were determined. The results showed that Fe, Mn, S (SO42-) were enriched in the intertidal area at different levels, very likely caused by fermentation of ancient woods. The presence of abundant iron-oxidizing bacteria (FeOB) and sulfate-reducing bacteria (SRB) in this intertidal zone was confirmed by HRTEM-SAED observation, and these bacteria were involved in Fe-S cycle to induce extracellular biomineralization. The negative δ34SV-CDT (-2.9‰) likely indicated the biogenic origin of iron-sulfide minerals in the beach mud at high sulfate reduction rate (SRR). These findings are helpful for under-standing the biogeochemical Fe-S cycle and biomineralization process at high organic matter deposition rate and high SRR in the intertidal zone, estuary, or near shoreline.An ancient wood layer dated at about 5600 cal. a BP by AMS14C dating was discovered in the intertidal zone, East China Sea. Samples affected by ancient woods, including fresh coast bedrock, weathering bedrock, seepage water from coast, seepage water from ancient wood layer, intertidal seawater, fresh water, beach mud, ancient wood barks and ancient peat, were collected for geochemical analysis. The beach mud and the bacteriogenic iron oxides （BIOS） in coastal seepage water were analyzed by min- eralogical and high-resolution transmission electron microscopy （HRTEM）-selected area electron dif- fraction （SAED） analysis. Inorganic sulfur compositions and b＇34S of the ancient peat and the beach mud were determined. The results showed that Fe, Mn, S （SO^-） were enriched in the intertidal area at different levels, very likely caused by fermentation of ancient woods. The presence of abundant iron- oxidizing bacteria （FeOB） and sulfate-reducing bacteria （SRB） in this intertidal zone was confirmed by HRTEM-SAED observation, and these bacteria were involved in Fe-S cycle to induce extracellular biomineralization. The negative ~4Sv.cDT （--2.9%o） likely indicated the biogenic origin of iron-sulfide minerals in the beach mud at high sulfate reduction rate （SRR）. These findings are helpful for under- standing the biogeochemical Fe-S cycle and biomineralization process at high organic matter deposition rate and high SRR in the intertidal zone, estuary, or near shoreline.

关 键 词：东中国海 氧化铁 潮间带 无机硫 树林 海洋法 选区电子衍射 透射电子显微镜 

分 类 号：P74[天文地球—海洋科学] S937[农业科学—渔业资源]