[M-IS05] Environmental, Socio-economic, and Climatic Changes in Northern Eurasia

[MIS05-05] Contribution of the disturbed areas to the soil CO2 emission fluxes in the middle taiga subzone of Central Siberia

*Anastasia Makhnykina^1,2、Elena Kukavskaya¹、Alexey Panov¹、Anatoly Prokushkin^1,2 (1.V.N. Sukachev Institute of forest Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk, Russia、2.Siberian Federal University, Krasnoyarsk, Russia)

キーワード：soil emission, boreal forest, wildfires, logging, Siberia, climate change

Forest ecosystems of the boreal zone are one of the key regions in maintaining the atmospheric carbon balance. Fires and logging are the main factors destabilizing forest ecosystems. Russia's boreal forests have been subject to intensive logging which significantly affects the biogeochemical processes including soil respiration. Recent climate changes result in an increase in the frequency of forest fires, while carbon emissions from the post-fire area return to the initial rate in about 30 years. The contribution of post-fire and post-cutting CO₂ emissions may radically change the functional role of the boreal forests into an additional source of greenhouse gases into the atmosphere. The main goal of this study was to assess the influence of a number of disturbance factors, such as clear cut logging, wildfire and their combined effect, on the amount of soil CO₂ emissions in Scots pine forest ecosystems of Central Siberia. Based on such an integrated approach to disturbance types, it will be possible to form reasonable opinion about the destructive impact of clear cuttings in comparison with the wildfires. We analyzed soil emission data from June to September 2024. At each of our study sites, lichen and moss synusias differed in soil moisture content values. The highest fluxes in the lichen synusia were observed at the logged site and the burned/logged site (2.7 ± 1.4 g C m^-2 day^-1), the lowest - at the burned site (1.5 ± 0.7 g C m^-2 day^-1). For the moss synusia, the highest fluxes were observed at the burned site (2.1 ± 1.5 g C m^-2 day^-1), and the lowest – at the site with the combined effect of two disturbance factors (1.3 ± 0.5 g C m^-2 day^-1). At the control undisturbed site, the flux rates from the lichen synusia were 50% higher than fr om the moss synusia. The obtained results underline the importance of natural and anthropogenic disturbance in controlling and modifying soil CO2 emission rates in boreal regions. This study has been supported by the grants the Russian Science Foundation, RSF 24-74-00159.