Can we leave it to nature? – post-fire tree regeneration in Białowieża Forest

Fire is an important disturbance in European forests, particularly in the Mediterranean region. However, the effects of climate change on fuel availability and fire weather, combined with the widespread dominance of conifer monocultures, high population density, and the significance of human-caused ignition, support predictions of increasing fire risk in temperate Central Europe – a phenomenon likely to necessitate expanded post-fire forest restoration. The non-intervention approach based on ecological succession is often not favoured over active restoration due to economic considerations or legal requirements. Nevertheless, natural ecosystem recovery has been shown to enable successful tree establishment, support biodiversity, and provide microclimatic benefits. Here, we present data on early (2–5 years) natural tree regeneration following non-stand-replacing wildfires in lowland coniferous forests of Białowieża, northeastern Poland, in relation to burn depth and selected microsite characteristics, collected from sample plots along parallel transects within burnt and unburnt forest sections. Our results demonstrate that fire promoted the establishment of diverse tree taxa, including Pinus, Picea, Quercus, Betula, Populus, and Salix. A higher number of saplings was recorded in burnt plots across all sites, with Pinus and Betula benefiting most from both fire disturbance and burn depth. Furthermore, our findings confirm the importance of fire disturbance for the natural regeneration of Scots pine, which is currently nearly absent in the Białowieża Forest otherwise. Our study contributes to the discussion on fire regimes, post-fire ecosystem recovery, and forest restoration in Central Europe, highlighting the great potential for a non-intervention approach after fire. It also provides baseline information to inform conservation and management strategies in the region.