Seasonality in the production, transport and emissions of CH4 from trees in boreal forest ecosystems

Boreal forests are considered as sinks and peatlands as sources of the strong greenhouse gas methane. Recently, upland vegetation has been found to emit methane to the atmosphere from a hitherto unknown process. If also upland trees produce considerably methane, forest ecosystems may change from a sink to a source of methane. In this study, we aim at quantifying the role of trees in the methane exchange between forest and the atmosphere, what processes lead to an emission and what to an uptake, and what environmental factors regulate methane dynamics in forest ecosystems. This study increases the understanding of greenhouse gas dynamics, sources and sinks in forest ecosystems, and as a result helps to improve the methane budget estimation in forest ecosystems.