PNAS Plus Significance Statements Iron oxides stimulate sulfate-driven anaerobic methane oxidation in seeps
نویسندگان
چکیده
Anaerobic oxidation of methane (AOM) coupled to sulfate reduction has been shown to consume up to 90% of the greenhouse gas methane produced within the subseafloor environment; however, the mechanism of this process has remained enigmatic. Here, we provide geochemical evidence based on sulfur, oxygen, and carbon isotopes for the involvement of iron oxides in sulfate-driven AOM inmethane seeps. Our results (pp. E4139–E4147) suggest that, beyond the function of iron as nutrient, the presence of iron oxides stimulates sulfate-driven AOM to a greater extent than in sediments with low concentrations of iron oxides. The isotope analyses further indicate that sulfate reduction in methane seep habitats differs than sulfate reduction in diffusive profiles in and above the sulfate–methane transition zone.
منابع مشابه
Iron oxides stimulate sulfate-driven anaerobic methane oxidation in seeps.
Seep sediments are dominated by intensive microbial sulfate reduction coupled to the anaerobic oxidation of methane (AOM). Through geochemical measurements of incubation experiments with methane seep sediments collected from Hydrate Ridge, we provide insight into the role of iron oxides in sulfate-driven AOM. Seep sediments incubated with (13)C-labeled methane showed co-occurring sulfate reduct...
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