Microbial hydrogen oxidation potential in seasonally hypoxic Baltic Sea sediments.

ABSTRACT: The majority of the organic matter (OM) degradation on the seafloor occurs in coastal regions. Since oxygen (O₂) becomes quickly depleted in the top sediments, most of the OM decomposition is driven by microbial sulfate reduction (SR) and fermentation, the latter generating molecular hydrogen (H₂). If the H₂ is not consumed by hydrogenotrophic microorganisms and accumulates in the sedimentary porewaters, OM degradation is hindered. Despite the importance of H₂ scavenging microorganisms for OM mineralization, the knowledge on H₂ oxidizers and their constraints in coastal marine sediments is still quite limited. Here we investigated the role of H₂ oxidizers in top (2 to 5 cm, suboxic-sulfidic) and bottom (18 to 22 cm, sulfidic

SUBMITTER: Adam-Beyer N 

PROVIDER: S-EPMC12007115 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature