title: Distribution patterns and possible influencing factors of As speciation in ornithogenic sediments from the Ross Sea region, East Antarctica.
abstract: Ornithogenic sediments are rich in toxic As (arsenic) compounds, posing a potential threat to local ecosystems. Here we analyzed the distribution of As speciation in three ornithogenic sediment profiles (MB6, BI and CC) collected from the Ross Sea region, East Antarctica. The distributions of total As and total P (phosphorus) concentrations were highly consistent in all three profiles, indicating that guano input is a major factor controlling total As distribution in the ornithogenic sediments. The As found in MB6 and CC is principally As(V) (arsenate), in BI As(III) (arsenite) predominates, but the As in fresh guano is largely composed of DMA (dimethylarsinate). The significant difference of As species between fresh guano and ornithogenic sediment samples may be related to diagenetic processes after deposition by seabirds. Based on analysis of the sedimentary environment in the studied sediments, we found that the redox conditions have an obvious influence on the As speciation distribution. Moreover, the distributions of As(III) and chlorophyll a in the MB6 and BI profiles are highly consistent, demonstrating that aquatic algae abundance may also influence the distribution patterns of As speciation in the ornithogenic sediments.
authors.affiliation: Institute of Polar Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
authors.forename: Chuangneng
authors.initials: C
authors.lastname: Lou
authors.affiliation: Institute of Polar Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China. Electronic address: ycx@ustc.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Instruments' Center for Physical Science, University of Science and Technology of China, Hefei 230026, China.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Liu
authors.affiliation: Institute of Polar Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
authors.forename: Libin
authors.initials: L
authors.lastname: Wu
authors.affiliation: Institute of Polar Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
authors.forename: Yaguang
authors.initials: Y
authors.lastname: Nie
authors.affiliation: Department of Biology and Marine Biology, University of North Carolina Wilmington, 601 S. College Road, Wilmington, NC 28403, USA.
authors.forename: Steven D
authors.initials: SD
authors.lastname: Emslie
mesh_terms: D000864:Antarctic Regions; D001151:Arsenic / Q000032:analysis*; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D001151:Arsenic
keywords: Arsenic speciation; Biovector; East Antarctica; Guano; Ornithogenic sediments