title: Vertical distribution of Fe and Fe(III)-reducing bacteria in the sediments of Lake Donghu, China.
abstract: In lake sediments, iron (Fe) is the most versatile element, and the redox cycling of Fe has a wide influence on the biogeochemical cycling of organic and inorganic substances. The aim of the present study was to analyze the vertical distribution of Fe and Fe(III)-reducing bacteria (FeRB) in the surface sediment (30 cm) of Lake Donghu, China. At the 3 sites we surveyed, FeRB and Fe(II)-oxidizing bacteria (FeOB) coexisted in anoxic sediments. Geobacter-related FeRB accounted for 5%-31% of the total Bacteria, while Gallionella-related FeOB accounted for only 0.1%-1.3%. A significant correlation between the relative abundance of poorly crystalline Fe and Geobacter spp. suggested that poorly crystalline Fe favored microbial Fe(III) reduction. Poorly crystalline Fe and Geobacter spp. were significantly associated with solid-phase Fe(II) and total inorganic phosphorus levels. Pore water Fe(II) concentrations negatively correlated with NO3(-) at all sites. We concluded that Geobacter spp. were abundant in the sediments of Lake Donghu, and the redox of Fe might participate in the cycling of nitrogen and phosphorus in sediments. These observations provided insight into the roles of microbial Fe cycling in lake sediments.
authors.affiliation: a Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.|b University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Cuicui
authors.initials: C
authors.lastname: Tian
authors.affiliation: a Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.|b University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Chunbo
authors.initials: C
authors.lastname: Wang
authors.affiliation: a Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.|b University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Tian
authors.affiliation: a Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.
authors.forename: Xingqiang
authors.initials: X
authors.lastname: Wu
authors.affiliation: a Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, People's Republic of China.
authors.forename: Bangding
authors.initials: B
authors.lastname: Xiao
mesh_terms: D001419:Bacteria / Q000302:isolation & purification* / Q000378:metabolism; D002681:China; D005290:Ferric Compounds / Q000378:metabolism*; D045302:Geobacter / Q000378:metabolism; D019015:Geologic Sediments / Q000382:microbiology*; D007501:Iron / Q000032:analysis*; D060106:Lakes / Q000382:microbiology*
chemical_list: D005290:Ferric Compounds; D007501:Iron
keywords: Fe faiblement cristallin; Fe reduction; Fe(III)-reducing bacteria; Lake Donghu; bactéries réductrices de Fe(III); distribution verticale; lac Donghu; poorly crystalline Fe; réduction de Fe; vertical distribution