title: Speciation change and redistribution of arsenic in soil under anaerobic microbial activities.
abstract: Arsenic speciation and behavior in soil are strongly affected by redox conditions. This work investigated speciation transformation and redistribution of arsenic in soil under anaerobic conditions. The effect of microbial sulfidogenesis on these processes was examined by addition of sulfate to the incubation systems. As(III) was found to be the dominant arsenic species in solution during the process of anaerobic incubation. The change of dissolved As concentration with incubation time showed "M" shaped profiles, e.g. the curves displaying two peaks at approximately 24 h and 240 h for the system with added sulfate. Arsenic was released and reduced to As(III) in the early stage of the incubation, and then resequestered into the solid phase. After excess sulfide was generated, the resequestered arsenic was released again (probably due to the dissolution of arsenic sulfide by dissolved sulfide ions) via the formation of thioarsenite. At the end of the incubation process, most of the dissolved arsenic was removed again from solution. The findings may have important implications to the fate of arsenic in flooded sulfur-rich soils.
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Liying
authors.initials: L
authors.lastname: Xu
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; Nanpiao Environmental Protection Bureau of Huludao, Liaoning 125027, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Wu
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. Electronic address: wangshaofeng@iae.ac.cn.
authors.forename: Shaofeng
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Zidan
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. Electronic address: yongfeng.jia@iae.ac.cn.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Jia
mesh_terms: D000693:Anaerobiosis; D001151:Arsenic / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D001152:Arsenicals / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D006851:Hydrochloric Acid / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D010084:Oxidation-Reduction; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D013431:Sulfates / Q000737:chemistry
chemical_list: D001152:Arsenicals; D012989:Soil Pollutants; D013431:Sulfates; D007501:Iron; D001151:Arsenic; D006851:Hydrochloric Acid
keywords: Anaerobic Microbial; Arsenic; Soil; Speciation; Sulfide