caa a22 4500 605517355 CHVBK 20210128100719.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s10533-015-0161-9 doi (NATIONALLICENCE)springer-10.1007/s10533-015-0161-9 Rates and pathways of methanogenesis in hypersaline environments as determined by 13C-labeling [Elektronische Daten] [Cheryl Kelley, Jeffrey Chanton, Brad Bebout] Rates and pathways of methane production were determined from photosynthetic soft microbial mats and gypsum-encrusted endoevaporites collected in hypersaline environments from California, Mexico and Chile, as well as an organic-rich mud from a pond in the El Tatio volcanic fields, Chile. Samples (mud, soft mats and endoevaporites) were incubated anaerobically with deoxygenated site water, and the increase in methane concentration through time in the headspaces of the incubation vials was used to determine methane production rates. To ascertain the substrates used by the methanogens, 13C-labeled methylamines, methanol, dimethylsulfide, acetate or bicarbonate were added to the incubations (one substrate per vial) and the stable isotopic composition of the resulting methane was measured. The vials amended with 13C-labeled methylamines produced the most 13C-enriched methane, generally followed by the 13C-labeled methanol-amended vials. The stable isotope data and the methane production rates were used to determine first order rate constants for each of the substrates at each of the sites. Estimates of individual substrate use revealed that the methylamines produced 55-92% of the methane generated, while methanol was responsible for another 8-40%. Springer International Publishing Switzerland, 2015 13C-labeling nationallicence Hypersaline environments nationallicence Methane nationallicence Stable carbon isotopes nationallicence Kelley Cheryl Department of Geological Sciences, University of Missouri, 65211, Columbia, MO, USA aut Chanton Jeffrey Department of Earth, Ocean and Atmospheric Science, Florida State University, 32306, Tallahassee, FL, USA aut Bebout Brad Exobiology Branch, NASA Ames Research Center, 94035, Moffett Field, CA, USA aut Biogeochemistry Springer International Publishing 126/3(2015-12-01), 329-341 0168-2563 126:3<329 2015 126 10533 https://doi.org/10.1007/s10533-015-0161-9 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-015-0161-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kelley Cheryl Department of Geological Sciences, University of Missouri, 65211, Columbia, MO, USA aut NATIONALLICENCE 700 1- Chanton Jeffrey Department of Earth, Ocean and Atmospheric Science, Florida State University, 32306, Tallahassee, FL, USA aut NATIONALLICENCE 700 1- Bebout Brad Exobiology Branch, NASA Ames Research Center, 94035, Moffett Field, CA, USA aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 126/3(2015-12-01), 329-341 0168-2563 126:3<329 2015 126 10533