Dataset Information

Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea.

ABSTRACT: Today's oceans store as much dissolved organic carbon (DOC) in the water column as there is CO₂ in the atmosphere, and as such dissolved organic matter (DOM) is an important component of the global carbon cycle. It was shown that in anoxic marine sediments, reduced sulfur species (e.g., H₂S) abiotically react with organic matter, contributing to carbon preservation. It is not known whether such processes also contribute to preserving DOM in ocean waters. Here, we show DOM sulfurization within the sulfidic waters of the Black Sea, by combining elemental, isotopic, and molecular analyses. Dissolved organic sulfur (DOS) is formed largely in the water column and not derived from sediments or allochthonous nonmarine sources. Our findings suggest that during large-scale anoxic events, DOM may accumulate through abiotic reactions with reduced sulfur species, having long-lasting effects on global climate by enhancing organic carbon sequestration.

SUBMITTER: Gomez-Saez GV

PROVIDER: S-EPMC8208715 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea.

Gomez-Saez Gonzalo V GV Dittmar Thorsten T Holtappels Moritz M Pohlabeln Anika M AM Lichtschlag Anna A Schnetger Bernhard B Boetius Antje A Niggemann Jutta J

Science advances 20210616 25

Today's oceans store as much dissolved organic carbon (DOC) in the water column as there is CO<sub>2</sub> in the atmosphere, and as such dissolved organic matter (DOM) is an important component of the global carbon cycle. It was shown that in anoxic marine sediments, reduced sulfur species (e.g., H<sub>2</sub>S) abiotically react with organic matter, contributing to carbon preservation. It is not known whether such processes also contribute to preserving DOM in ocean waters. Here, we show DOM s ...[more]

PMID: 34134989

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Dataset Information

Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea.

Publications

Sulfurization of dissolved organic matter in the anoxic water column of the Black Sea.

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