Abstract
The article examines the features of post-fire (post-pyrogenic) dynamics of the forest floor cover in forest ecosystems of the Kostanay region. The aim of the study is to assess the patterns of recovery of forest litter, leaf, herbaceous, and woody litterfall, as well as the dynamics of charcoal residues and ash on burned sites of different ages, taking into account site conditions. The methodological basis consisted of field studies conducted on sample plots, including the assessment of litter reserves (t/ha), measurement of forest litter thickness, analysis of pyrogenic residues, and calculation of the regeneration index using remote sensing data (NDVI, Sentinel-2, Landsat-8). The results show that on burned areas of 2022 the forest litter layer is minimal (1.2...1.3 cm), while the stocks of leaf and woody litter are reduced (0.2...0.6 and 0.5...0.6 t/ha, respectively), and the content of charcoal residues reaches 0.6...1.0 t/ha. On sites affected by fires in 2004...2010, the litter thickness increases to 4.0...4.5 cm, pyrogenic carbon decreases to 0.2...0.5 t/ha, and the regeneration index rises to 0.60...0.80. Background areas are characterized by stabilized values (litter thickness 5.2...6.2 cm; regeneration index 0.72...0.86). It was revealed that recovery processes are slower under xerophilic conditions, whereas in mesophilic and hygrophilic habitats humification and regeneration processes occur significantly faster. The obtained results confirm that the rate of post-fire succession is determined by the year of the fire, fire intensity, and soil-hydrological conditions. The forest floor cover can be considered an integral indicator of forest ecosystem recovery and may be used in developing measures for their sustainable restoration.