DOI: 10.1002/2013GB004778
Scopus记录号: 2-s2.0-84910121558
论文题名: Production of dissolved organic carbon enriched in deoxy sugars representing an additional sink for biological C drawdown in the Amazon River plume
作者: Meador T ; B ; , Aluwihare L ; I
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2014
卷: 28, 期: 10 起始页码: 1149
结束页码: 1161
语种: 英语
英文关键词: biocomplexity
; DOC advection
; marine snow
; polysaccharides
; Richelia
Scopus关键词: carbon sequestration
; carbon sink
; diatom
; dissolved organic carbon
; isotopic composition
; marine snow
; phytoplankton
; river plume
; sugar
; Amazon River
; Atlantic Ocean
; Atlantic Ocean (North)
; Orinoco River
; Richelia
英文摘要: In North Atlantic waters impacted by discharges from the Amazon and Orinoco Rivers, where planktonic diatom-diazotroph associations (DDA) were active, we observed that an average (± standard deviation) of 61 ± 12% of the biological drawdown of dissolved inorganic carbon (DIC) was partitioned into the accumulating total organic carbon pool, representing a flux of up to 9 ± 4 Tg C yr-1. This drawdown corresponded with chemical alteration of ultrafiltered dissolved organic matter (UDOM), including increases in stable C isotopic composition (δ13C) and C:N. The dissolved carbohydrate component of UDOM also increased with biological DIC drawdown and diatom-associated diazotroph (i.e., Richelia) abundance. New carbohydrates could be distinguished by distinctively high relative abundances of deoxy sugars (up to 55% of monosaccharides), which may promote aggregate formation and enhance vertical carbon export. The identified production of non-Redfieldian, C-enriched UDOM thus suggests a mechanism to explain enhanced C sequestration associated with DDA N2 fixation, which may be widespread in mesohaline environments. Key Points Up to 9 ± 4 Tg C per year accumulate as TOC in the surface mesohaline oceanUDOC produced in the diatom-diazotroph bloom was enriched in deoxy sugarsC-rich UDOM may be a conduit for diazotroph-driven C sequestration © 2014. 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/77473
Appears in Collections: 气候变化事实与影响
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作者单位: Geosciences Research Division, Scripps Institution of Oceanography, San Diego, CA, United States; Now at MARUM Center for Marine Environmental Sciences, Department of Geosciences, University of Bremen, Bremen, Germany
Recommended Citation:
Meador T,B,, Aluwihare L,et al. Production of dissolved organic carbon enriched in deoxy sugars representing an additional sink for biological C drawdown in the Amazon River plume[J]. Global Biogeochemical Cycles,2014-01-01,28(10)