Carbonate-hosted methanotrophy represents an unrecognized methane sink in the deep sea

TitleCarbonate-hosted methanotrophy represents an unrecognized methane sink in the deep sea
Publication TypeJournal Article
Year of Publication2014
AuthorsMarlow J.J, Steele J.A, Ziebis W., Thurber AR, Levin L.A, Orphan V.J
JournalNature Communications
Volume5
Date Published2014/10
Type of ArticleArticle
ISBN Number2041-1723
Accession NumberWOS:000343978000011
Keywordsanaerobic oxidation; Cascadia; cold seeps; continental-margin; eel river-basin; gas hydrate growth; lipid biomarker; margin; microbial life; offshore california; sulfate reduction
Abstract

The atmospheric flux of methane from the oceans is largely mitigated through microbially mediated sulphate-coupled methane oxidation, resulting in the precipitation of authigenic carbonates. Deep-sea carbonates are common around active and palaeo-methane seepage, and have primarily been viewed as passive recorders of methane oxidation; their role as active and unique microbial habitats capable of continued methane consumption has not been examined. Here we show that seep-associated carbonates harbour active microbial communities, serving as dynamic methane sinks. Microbial aggregate abundance within the carbonate interior exceeds that of seep sediments, and molecular diversity surveys reveal methanotrophic communities within protolithic nodules and well-lithified carbonate pavements. Aggregations of microbial cells within the carbonate matrix actively oxidize methane as indicated by stable isotope FISH-nanoSIMS experiments and (CH4)-C-14 radiotracer rate measurements. Carbonate-hosted methanotrophy extends the known ecological niche of these important methane consumers and represents a previously unrecognized methane sink that warrants consideration in global methane budgets.

DOI10.1038/ncomms6094
Short TitleNat. Commun.
Integrated Research Themes: 
Student Publication: 
No
Research Topics: