Elevated methane concentrations in trees of an upland forest
Article first published online: 9 AUG 2012
©2012. American Geophysical Union. All Rights Reserved.
Geophysical Research Letters
Volume 39, Issue 15, August 2012
How to Cite
2012), Elevated methane concentrations in trees of an upland forest, Geophys. Res. Lett., 39, L15705, doi:10.1029/2012GL052361., , , , and (
- Issue published online: 9 AUG 2012
- Article first published online: 9 AUG 2012
- Manuscript Accepted: 3 JUL 2012
- Manuscript Revised: 1 JUL 2012
- Manuscript Received: 15 MAY 2012
- greenhouse gas emissions;
 There is intense debate about whether terrestrial vegetation contributes substantially to global methane emissions. Although trees may act as a conduit for methane release from soils to atmosphere, the debate centers on whether vegetation directly produces methane by an uncharacterized, abiotic mechanism. A second mechanism of direct methane production in plants occurs when methanogens – microorganisms in the domain Archaea – colonize the wood of living trees. In the debate this biotic mechanism has largely been ignored, yet conditions that promote anaerobic activity in living wood, and hence potentially methane production, are prevalent across forests. We find average, growing season, trunk-gas methane concentrations >15,000μL·L−1in common, temperate-forest species. In upland habitat (where soils are not a significant methane source), concentrations are 2.3-times greater than in lowland areas, and wood cores produce methane in anaerobic, lab-assays. Emission rate estimates from our upland site are 52 ± 9.5 ng CH4 m−2 s−1; rates that are of a similar magnitude to the soil methane sink in temperate forest, and equivalent in global warming potential to ∼18% of the carbon likely sequestered by this forest. Microbial infection of one of the largest, biogenic sinks for carbon dioxide, living trees, might result in substantial, biogenic production of methane.