Active pathways of anaerobic methane oxidation across contrasting riverbeds.

ABSTRACT: Anaerobic oxidation of methane (AOM) reduces methane emissions from marine ecosystems but we know little about AOM in rivers, whose role in the global carbon cycle is increasingly recognized. We measured AOM potentials driven by different electron acceptors, including nitrite, nitrate, sulfate, and ferric iron, and identified microorganisms involved across contrasting riverbeds. AOM activity was confined to the more reduced, sandy riverbeds, whereas no activity was measured in the less reduced, gravel riverbeds where there were few anaerobic methanotrophs. Nitrite-dependent and nitrate-dependent AOM occurred in all sandy riverbeds, with the maximum rates of 61.0 and 20.0 nmol CO₂ g^-1 (dry sediment) d^-1, respectively, while sulfate-dependent and f

SUBMITTER: Shen LD 

PROVIDER: S-EPMC6461903 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature