An active atmospheric methane sink in high Arctic mineral cryosols.
ISME J
; 9(8): 1880-91, 2015 Aug.
Article
de En
| MEDLINE
| ID: mdl-25871932
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.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Sol
/
Microbiologie du sol
/
Bactéries
/
Méthane
Type d'étude:
Prognostic_studies
Pays/Région comme sujet:
America do norte
Langue:
En
Journal:
ISME J
Sujet du journal:
MICROBIOLOGIA
/
SAUDE AMBIENTAL
Année:
2015
Type de document:
Article
Pays d'affiliation:
États-Unis d'Amérique