title: An active atmospheric methane sink in high Arctic mineral cryosols.
abstract: Methane (CH4) emission by carbon-rich cryosols at the high latitudes in Northern Hemisphere has been studied extensively. In contrast, data on the CH4 emission potential of carbon-poor cryosols is limited, despite their spatial predominance. This work employs CH4 flux measurements in the field and under laboratory conditions to show that the mineral cryosols at Axel Heiberg Island in the Canadian high Arctic consistently consume atmospheric CH4. Omics analyses present the first molecular evidence of active atmospheric CH4-oxidizing bacteria (atmMOB) in permafrost-affected cryosols, with the prevalent atmMOB genotype in our acidic mineral cryosols being closely related to Upland Soil Cluster α. The atmospheric (atm) CH4 uptake at the study site increases with ground temperature between 0 °C and 18 °C. Consequently, the atm CH4 sink strength is predicted to increase by a factor of 5-30 as the Arctic warms by 5-15 °C over a century. We demonstrate that acidic mineral cryosols are a previously unrecognized potential of CH4 sink that requires further investigation to determine its potential impact on larger scales. This study also calls attention to the poleward distribution of atmMOB, as well as to the potential influence of microbial atm CH4 oxidation, in the context of regional CH4 flux models and global warming.
authors: Department of Geosciences, Princeton University, Princeton, NJ, USA.
authors: M C Y
authors: MC
authors: Lau
authors: Department of Geosciences, Princeton University, Princeton, NJ, USA.
authors: B T
authors: BT
authors: Stackhouse
authors: Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, USA.
authors: A C
authors: AC
authors: Layton
authors: Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, USA.
authors: A
authors: A
authors: Chauhan
authors: Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, USA.
authors: T A
authors: TA
authors: Vishnivetskaya
authors: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
authors: K
authors: K
authors: Chourey
authors: Department of Natural Resource Sciences, McGill University, Ste. Anna de Bellevue, Quebec, Canada.
authors: J
authors: J
authors: Ronholm
authors: 1] Department of Natural Resource Sciences, McGill University, Ste. Anna de Bellevue, Quebec, Canada [2] Vale Living with Lakes Centre, Laurentian University, Sudbury, Ontario, Canada.
authors: N C S
authors: NC
authors: Mykytczuk
authors: Department of Geological Sciences, The University of Texas at Austin, Austin, TX, USA.
authors: P C
authors: PC
authors: Bennett
authors: Department of Natural Resource Sciences, McGill University, Ste. Anna de Bellevue, Quebec, Canada.
authors: G
authors: G
authors: Lamarche-Gagnon
authors: Department of Geosciences, Princeton University, Princeton, NJ, USA.
authors: N
authors: N
authors: Burton
authors: Department of Geography, McGill University, Montreal, Quebec, Canada.
authors: W H
authors: WH
authors: Pollard
authors: Department of Geological Sciences, The University of Texas at Austin, Austin, TX, USA.
authors: C R
authors: CR
authors: Omelon
authors: Department of Geosciences, Princeton University, Princeton, NJ, USA.
authors: D M
authors: DM
authors: Medvigy
authors: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
authors: R L
authors: RL
authors: Hettich
authors: Center for Environmental Biotechnology, University of Tennessee, Knoxville, TN, USA.
authors: S M
authors: SM
authors: Pfiffner
authors: Department of Natural Resource Sciences, McGill University, Ste. Anna de Bellevue, Quebec, Canada.
authors: L G
authors: LG
authors: Whyte
authors: Department of Geosciences, Princeton University, Princeton, NJ, USA.
authors: T C
authors: TC
authors: Onstott
mesh_terms: D001110:Arctic Regions; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000235:genetics; D002170:Canada; D005798:Genes, Bacterial; D057232:Global Warming; D008697:Methane / Q000032:analysis*; D008903:Minerals; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000235:genetics; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D013696:Temperature; D065929:Tundra
chemical_list: D001426:Bacterial Proteins; D008903:Minerals; D012987:Soil; D010105:Oxygenases; D008697:Methane