EGU22-13360
https://doi.org/10.5194/egusphere-egu22-13360
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Methane source-sink behaviour in upland trees spanning a global climate gradient

Vincent Gauci1,2, Sunitha Pangala3, Alexander Shenkin5,10, Josep Barba1,2,4, David Bastviken6, Viviane Figueiredo7, Carla Gomez8, Alex Enrich-Prast6,9, Emma Sayer3,7, Tainá Stauffer9, Bertie Welch8, Myles Allen5, and Yadvinder Malhi5
Vincent Gauci et al.
  • 1BIFoR Birmingham Institute of Forest Research, University of Birmingham, Edgbaston, Birmingham, UK
  • 2School of Geography Earth and Environmental Science, University of Birmingham, Edgbaston, Birmingham, UK
  • 3Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA1 4YQ, UK
  • 4CREAF, Cerdanyola del Vallès, Catalonia, SP
  • 5Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford, UK
  • 6Department of Thematic Studies – Environmental Change, Linköping University, Linkoping SE-581 83, Sweden
  • 7Smithsonian Tropical Research Institute, Balboa, Ancon, P.O. Box 0843-03092, Panama, Republic of Panama
  • 8School of Environment, Earth and Ecosystem Studies, The Open University, Milton Keynes, UK
  • 9Multiuser Unit of Environmental Analysis, University Federal of Rio de Janeiro, Rio de Janeiro, Brazil
  • 10School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA

Forests play an important role in the exchange of radiatively important gases with the atmosphere. Previous studies have shown that in both temperate and tropical wetland forests tree stems are significant sources of methane, yet little is known about tree stem trace greenhouse gas dynamics in drier, free-draining soils that dominate global forested areas. Here, we examine methane fluxes on tree stems spanning a climate gradient of upland forests and floodplain forest across 4 locations in the Amazon, Brazil (Cunia, Rios Negro, Solimoes and Tapajos), lowland tropical forest on free-draining soils in Panama, Central America (Barro Colorado Nature Monument), deciduous woodland in the United Kingdom (Wytham, Oxfordshire) and boreal forest in Sweden. We found that trees behaved as both methane sources (near the tree base) and sinks (higher up the tree stem) across tropical, temperate and boreal sites and are highly variable, yet we were able to identify a broad correlation between the size of tree stem methane uptake fluxes and mean annual temperature across the climate gradient. The vertical spatial patterns of flux up the individual measured trees and climate gradient temperature-methane flux relationship together with revised LiDAR derived tree surface allometry permitted global scaling of fluxes in upland forest. Results of this scaling together with the implications of this refined understanding of the global methane cycle under various scenarios are discussed.

How to cite: Gauci, V., Pangala, S., Shenkin, A., Barba, J., Bastviken, D., Figueiredo, V., Gomez, C., Enrich-Prast, A., Sayer, E., Stauffer, T., Welch, B., Allen, M., and Malhi, Y.: Methane source-sink behaviour in upland trees spanning a global climate gradient, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13360, https://doi.org/10.5194/egusphere-egu22-13360, 2022.