DOI: 10.1007/s10533-014-0049-0
Scopus记录号: 2-s2.0-84913529362
论文题名: Origin-specific molecular signatures of dissolved organic matter in the Lena Delta
作者: Dubinenkov I. ; Flerus R. ; Schmitt-Kopplin P. ; Kattner G. ; Koch B.P.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2015
卷: 123, 期: 2018-01-02 语种: 英语
英文关键词: Arctic
; DOM
; FT-ICR MS
; Lena Delta
; Molecular markers
; Permafrost
英文摘要: Large Arctic rivers discharge significant amounts of dissolved organic matter (DOM) into the Arctic Ocean. We sampled natural waters of the Lena River, the Buor-Khaya Bay (Laptev Sea), permafrost melt water creeks, ice complex melt water creeks and a lake. The goal of this study was to characterize the molecular DOM composition with respect to different water bodies within the Lena Delta. We aimed at an identification of source-specific DOM molecular markers and their relative contribution to DOM of different origin. The molecular characterization was performed for solid-phase extracted DOM by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Average dissolved organic carbon concentrations in the original samples were 490 ± 75 µmol C L−1 for riverine and bay samples and 399 ± 115 µmol C L−1 for permafrost melt water creeks. Average TDN concentrations were elevated in the permafrost melt waters (19.7 ± 7.1 µmol N L−1) in comparison to the river and the bay (both 13.2 ± 2.6 µmol N L−1). FT-ICR MS and statistical tools demonstrated that the origin of DOM in the Lena Delta was systematically reflected in its molecular composition. Magnitude weighted parameters calculated from MS data (O/Cwa, H/Cwa, C/Nwa) highlighted preliminary sample discrimination. The highest H/Cwa of 1.315 was found for DOM in melt water creeks in comparison to 1.281 for river and 1.230 for the bay samples. In the bay samples we observed a higher fraction of oxygen-rich components which was reflected in an O/Cwa ratio of 0.445 in comparison to 0.425 and 0.427 in the river and creeks, respectively. From the southernmost location to the bay a relative depletion of nitrogenous molecular markers and an enrichment of oxidized DOM components occurred. The highest contribution of nitrogenous components was indicative for creeks reflected in a C/Nwa of 104 in comparison to 143 and 176 in the river and bay, respectively. These observations were studied on a molecular formula level using principal component and indicator value analyses. The results showed systematic differences with respect to water origin and constitute an important basis for a better mechanistic understanding of DOM transformations in the changing Arctic rivers. © 2014, Springer International Publishing Switzerland. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83571
Appears in Collections: 气候减缓与适应 气候变化事实与影响
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作者单位: Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, Bremerhaven, Germany; Biological Oceanography, GEOMAR Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, Kiel, Germany; Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstraße 1, Neuherberg, Germany; Technische Universität München, Alte Akademie 10, Freising, Germany; University of Applied Sciences, An der Karlstadt 8, Bremerhaven, Germany
Recommended Citation:
Dubinenkov I.,Flerus R.,Schmitt-Kopplin P.,et al. Origin-specific molecular signatures of dissolved organic matter in the Lena Delta[J]. Biogeochemistry,2015-01-01,123(2018-01-02)