Open Access Green as soon as Postprint is submitted to ZB.
Photochemical production of polyols arising from significant photo-transformation of dissolved organic matter in the oligotrophic surface ocean.
Mar. Chem. 163, 10-18 (2014)
Ultrahigh resolution mass spectrometry of marine dissolved organic matter (DOM) has suggested the presence of many common molecular compositions throughout the open ocean. The majority of these supposedly ubiquitous molecules was concluded to represent the refractory marine DOM pool. This study demonstrates that 24 h of exposure of Atlantic and Pacific surface DOM to simulated sunlight causes phototransformation of about half of these supposedly refractory molecular compositions. It is suggested that these transformations are related to indirect photobleaching possibly involving reactive oxygen species (e.g. hydroxyl radicals), because very little change in the fluorescent component of the DOM (FDOM) was observed during the photo-degradation experiments. A significant decline in average mass with distinct decrease of average O/C ratios and concomitant increase of H/C ratios was observed. NMR spectra revealed a decrease in aromatic and olefinic unsaturation and the formation of a limited and near identical suite of oxygenated aliphatic compounds in both Atlantic and Pacific surface DOM. Their NMR characteristics indicated a mixture of about 10 polyols that are plausible products of convergent pathways of photochemical carbohydrate decomposition and oxidation of functionalized, branched aliphatic compounds. These prominent photochemical signature molecules amounted to -2% of total proton NMR integral and are expected to be quickly consumed by various microorganisms in the open ocean. These results may suggest a fast photo-induced large-scale cycling of DOM within the surface ocean dynamic equilibrium of photo- and bio-transformations.
Impact Factor
Scopus SNIP
Web of Science
Times Cited
Times Cited
Scopus
Cited By
Cited By
Altmetric
3.200
1.750
32
41
Annotations
Special Publikation
Hide on homepage
Publication type
Article: Journal article
Document type
Scientific Article
Keywords
Ft-ms ; Nmr ; Dissolved Organic Matter ; Dom ; Polyols ; Marine Photochemistry; Resonance Mass-spectrometry; Solid-phase Extraction; Fulvic-acids; Sea-water; Carbon; Seawater; River; Degradation; Component; Spectra
Language
english
Publication Year
2014
HGF-reported in Year
2014
ISSN (print) / ISBN
0304-4203
e-ISSN
0304-4203
Journal
Marine Chemistry
Quellenangaben
Volume: 163,
Pages: 10-18
Publisher
Elsevier
Publishing Place
Amsterdam
Reviewing status
Peer reviewed
Institute(s)
Research Unit BioGeoChemistry and Analytics (BGC)
POF-Topic(s)
30202 - Environmental Health
Research field(s)
Environmental Sciences
PSP Element(s)
G-504800-001
WOS ID
WOS:000337872000002
Scopus ID
84899679883
Erfassungsdatum
2014-07-28