Simulating Changes in Fires and Ecology of the 21st Century Eurasian Boreal Forests of Siberia

Wildfires release the greatest amount of carbon into the atmosphere compared to other forest disturbances. To understand how current and potential future fire regimes may affect the role of the Eurasian boreal forest in the global carbon cycle, we employed a new, spatially-explicit fire module DISTURB-F (DISTURBance-Fire) in tandem with a spatially-explicit, individually-based gap dynamics model SIBBORK (SIBerian BOReal forest simulator calibrated to Krasnoyarsk Region). DISTURB-F simulates the effect of forest fire on the boreal ecosystem, namely the mortality of all or only the susceptible trees (loss of biomass, i.e., carbon) within the forested landscape. The fire module captures some important feedbacks between climate, fire and vegetation structure. We investigated the potential climate-driven changes in the fire regime and vegetation in middle and south taiga in central Siberia, a region with extensive boreal forest and rapidly changing climate. The output from this coupled simulation can be used to estimate carbon losses from the ecosystem as a result of fires of different sizes and intensities over the course of secondary succession (decades to centuries). Furthermore, it may be used to assess the post-fire carbon storage capacity of potential future forests, the structure and composition of which may differ significantly from current Eurasian boreal forests due to regeneration under a different climate.