DOI: 10.1002/gbc.20038
Scopus记录号: 2-s2.0-84881100743
论文题名: The contribution of Fe(III) and humic acid reduction to ecosystem respiration in drained thaw lake basins of the Arctic Coastal Plain
作者: Lipson D ; A ; , Raab T ; K ; , Goria D ; , Zlamal J
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2013
卷: 27, 期: 2 起始页码: 399
结束页码: 409
语种: 英语
英文关键词: Arctic
; Carbon Cycle
; Climate Change
; Fe Reduction
; Humic Substances
; Peat
Scopus关键词: Anaerobic respiration
; Arctic
; Arctic coastal plains
; Carbon cycles
; Fe reductions
; Humic substances
; Surface organic layers
; Terminal electron acceptors
; Biological materials
; Climate change
; Iron research
; Lakes
; Organic acids
; Peat
; Thawing
; Organic minerals
; biogeochemistry
; carbon cycle
; chelation
; climate change
; coastal plain
; humic acid
; iron
; iron oxide
; peat
; reduction
; respiration
; Arctic Ocean
英文摘要: Previous research showed that anaerobic respiration using iron (Fe) oxides as terminal electron acceptor contributed substantially to ecosystem respiration (ER) in a drained thaw lake basin (DTLB) on the Arctic coastal plain. As DTLBs age, the surface organic layer thickens, progressively burying the Fe-rich mineral layers. We therefore hypothesized that Fe(III) availability and Fe reduction would decline with basin age. We studied four DTLBs across an age gradient, comparing seasonal changes in the oxidation state of dissolved and extractable Fe pools and the estimated contribution of Fe reduction to ER. The organic layer thickness did not strictly increase with age for these four sites, though soil Fe levels decreased with increasing organic layer thickness. However, there were surprisingly high levels of Fe minerals in organic layers, especially in the ancient basin where cryoturbation may have transported Fe upward through the profile. Net reduction of Fe oxides occurred in the latter half of the summer and contributed an estimated 40-45% to ecosystem respiration in the sites with the thickest organic layers and 61-63% in the sites with the thinnest organic layers. All sites had high concentrations of soluble Fe(II) and Fe(III), explained by the presence of siderophores, and this pool became progressively more reduced during the first half of the summer. Redox titrations with humic acid (HA) extracts and chelated Fe support our view that this pattern indicates the reduction of HA during this interval. We conclude that Fe(III) and HA reductions contribute broadly to ER in the Arctic coastal plain. ©2013. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77617
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Biology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182-4614, United States; Carnegie Institution for Science, Stanford, CA, United States
Recommended Citation:
Lipson D,A,, Raab T,et al. The contribution of Fe(III) and humic acid reduction to ecosystem respiration in drained thaw lake basins of the Arctic Coastal Plain[J]. Global Biogeochemical Cycles,2013-01-01,27(2)