Biomineralization process occurring in iron mud of coastal seepage area of Zhoushan Island, Zhejiang Province  

作　　者：WU ZiJun JIA Nan YUAN LinXi SUN LiGuang 

机构地区：[1]School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China

出　　处：《Chinese Science Bulletin》2008年第12期1894-1904,共11页

基　　金：the Important Direction Project of the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No.KZCX3-SW-151);China Post-doctoral Science Foundation (Grant No.20060400723)

摘　　要：The biomineralization process of iron oxidizing bacteria and its influence on accumulation of metals were investigated by modern biological observation techniques (i.e., SEM and TEM) and geochemical methods, in coastal area of Zhoushan Island, Zhejiang province where a thick ancient wood layers were buried, Results show that the iron mud samples mainly contain Leptothrix-like sheaths and Gal-lionella-like stalks, which are known as neutrophilic iron-oxidizing bacteria. These two bacteria are present as obviously different abundance in two sampling sites, which may be regulated by the geo-chemistry of seepage water. The biomineralization product of iron oxidizing bacteria is ferrihydrite, a poorly ordered iron oxide, and formation of amorphous mineral is affected by the factors of bacteria, minor Si and temperature preventing any further transformation into more crystalline phases. Organic functional groups, extracellular polymers and surface charges can provide favorable nucleation sites or template for formation of iron precipitates on the bacterial surface. The mineralization process of the iron oxidizing bacteria is divided into different stages, i.e., extracellular mineralization, intracellular mineralization and the whole cell mineralization. Furthermore, due to BIOS containing the bacterial organic matter, the accumulation capacity of metals specially Fe and Co is highly increased, suggest-ing that BIOS exert a degree of controlling in the cycling of metal elements in seepage area.The biomineralization process of iron oxidizing bacteria and its influence on accumulation of metals were investigated by modern biological observation techniques （i.e., SEM and TEM） and geochemical methods, in coastal area of Zhoushan Island, Zhejiang province where a thick ancient wood layers were buried, Results show that the iron mud samples mainly contain Leptothrix-like sheaths and Gallionella-like stalks, which are known as neutrophilic iron-oxidizing bacteria. These two bacteria are present as obviously different abundance in two sampling sites, which may be regulated by the geochemistry of seepage water. The biomineralization product of iron oxidizing bacteria is ferrihydrite, a poorly ordered iron oxide, and formation of amorphous mineral is affected by the factors of bacteria, minor Si and temperature preventing any further transformation into more crystalline phases. Organic functional groups, extracellular polymers and surface charges can provide favorable nucleation sites or template for formation of iron precipitates on the bacterial surface. The mineralization process of the iron oxidizing bacteria is divided into different stages, i.e., extracellular mineralization, intracellular mineralization and the whole cell mineralization. Furthermore, due to BIOS containing the bacterial organic matter, the accumulation capacity of metals specially Fe and Co is highly increased, suggesting that BIOS exert a degree of controlling in the cycling of metal elements in seepage area.

关 键 词：生物矿化过程 铁矿 浙江省 渗流水 

分 类 号：P57[天文地球—矿物学]