Comparison of Estimates of Postfire Forest Mortality in Siberia Based on Remote Sensing Data

Estimates of the areas of stand-replacing fires in Siberia (within the boundaries of 50°–75° N, 60°–160° E) were compared. The analysis used data from the open catalog of the GFC (Global Forest Change) tree loss monitoring service and satellite monitoring of fires in Siberia for the period 2001–2023. Information on tree stand mortality is detailed with reference to the dominant vegetation cover options in the region, including larch stands, pine stands, and forests with a predominance of dark coniferous and deciduous species. Combined analysis of the data allowed us to identify the average long-term values of fatal changes in vegetation cover caused by fires, the share of which in different years amounted to 20–90% of the total losses of forest stands reflected in the GFC service materials for the Siberian region. A detailed analysis of the degree of fire impact on the main forest-forming species of Siberia allows us to state that the share of stand-replacing fires in the overall statistics of losses of light coniferous forest stands according to the GFC varies at the level of 40–90% of the area, for forests with a predominance of dark conifers, and for deciduous forests, this estimate is lower—up to 20–40%. Thus, it has been shown that out of the annual loss of forest stands in Siberia amounting to 2.6 million ha, fires account for up to 1.9 million ha. A significant direct relationship with an approximation reliability of 0.95 (at a significance level of p < 0.01) was also found between the areas of forest loss according to GFC data and the increase in fire intensity in Siberia in the time intervals of 2001–2012 and 2013–2023.