Until recently, tree stem surfaces were thought to be inert to methane (CH4) exchange with the atmosphere. However, technological advances in CH4 analysis and development of stem chamber systems for gas flux determination have enabled intensive field measurements of CH4 fluxes, not only from soils but also from tree stem surfaces. In contrast to long-standing assumptions, tree stems have often been detected as emitters of CH4 with emission rates affected by factors including tree species, forest type, and environmental conditions. The mechanisms, spatial and temporal patterns, and environmental drivers behind the net flux of CH4 are complex, yet the potential implications for the global carbon cycle are large. This Virtual Issue highlights papers from a broad and interdisciplinary set of authors that contribute to our new understanding on methane emissions from tree stems and sets out the Key challenges and opportunities for future research.

• Published: 24 January 2024

Editors:

Josep Barba,  Paul E. Brewer,  Sunitha R. Pangala,  Katerina Machacova

• methane
• tree stem
• carbon cycle