caa a22 4500 605517118 CHVBK 20210128100718.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s10533-014-0049-0 doi (NATIONALLICENCE)springer-10.1007/s10533-014-0049-0 Origin-specific molecular signatures of dissolved organic matter in the Lena Delta [Elektronische Daten] [I. Dubinenkov, R. Flerus, P. Schmitt-Kopplin, G. Kattner, B. Koch] 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±75µmolCL−1 for riverine and bay samples and 399±115µmolCL−1 for permafrost melt water creeks. Average TDN concentrations were elevated in the permafrost melt waters (19.7±7.1µmolNL−1) in comparison to the river and the bay (both 13.2±2.6µmolNL−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. Springer International Publishing Switzerland, 2014 Arctic nationallicence Lena Delta nationallicence Permafrost nationallicence DOM nationallicence FT-ICR MS nationallicence Molecular markers nationallicence Dubinenkov I. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut Flerus R. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut Schmitt-Kopplin P. Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany aut Kattner G. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut Koch B. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut Biogeochemistry Springer International Publishing 123/1-2(2015-03-01), 1-14 0168-2563 123:1-2<1 2015 123 10533 https://doi.org/10.1007/s10533-014-0049-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-014-0049-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Dubinenkov I. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Flerus R. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Schmitt-Kopplin P. Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany aut NATIONALLICENCE 700 1- Kattner G. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut NATIONALLICENCE 700 1- Koch B. Ecological Chemistry, Alfred-Wegener-Institut Helmholtz-Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570, Bremerhaven, Germany aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 123/1-2(2015-03-01), 1-14 0168-2563 123:1-2<1 2015 123 10533