Enhanced autosuccession after wildfire in a transitional sub-Mediterranean forest ecosystem: evidence from the Kras Plateau (Slovenia).

Introduction: Wildfires are becoming an increasingly prevalent phenomenon in sub-Mediterranean regions, including areas where the vegetation is not historically adapted to fire. However, post-fire successional dynamics in these regions remain poorly documented. Methods: Vegetation was monitored annually for three years (2023-2025) following a major wildfire on the Kras Plateau (SW Slovenia) in 2022. Monitoring was conducted in 50 permanent plots assigned to five fire-severity classes, including unburned control plots (class 0) and four burned classes (classes 1, 2a, 2b, and 3). We analyzed species composition, vegetation structure, ecological indicator values, species origin and habitat preference, and plant functional traits using ordination and trait-based approaches. Results: Post-fire succession followed an initial floristic composition model and an enhanced autosuccessional pathway across all fire-severity classes. The early dominance of ephemeral and ruderal species declined rapidly, while the abundance of perennial grasses, shrubs, and resprouting woody species increased. Functional traits shifted along the C-R axis of Grime's CSR strategy framework: from ruderal towards competitive and stress-tolerant, and successional trajectories consistently converged towards zonal thermophilous deciduous forest communities. High amounts of precipitation facilitated rapid structural recovery, with shrubland developing within three years. Conclusion: Sub-Mediterranean forest vegetation on the Kras Plateau exhibits high resilience to wildfire, despite limited historical adaptation to fire. Enhanced autosuccession, combined with favorable post-fire moisture conditions, enables rapid recovery and reduces the likelihood of long-term degradation or the establishment of persistent post-fire shrublands.