The process of vegetation recovery and burn probability changes in post-burn boreal forests in northeast China

Abstract

Background Repeated fires may slow the recovery process in burned areas, thus affecting ecological succession. Aims This paper explores the changes in likelihood of reburn and fire behaviours in various phases of vegetation recovery. Methods We used field survey data and the Enhanced Vegetation Index (EVI) to assess vegetation recovery in boreal forests after fires at both landscape and field scales. The Burn-P3 model was used to simulate burn probability and fire behaviours and then evaluate the overall fire likelihood and potential behaviours in different recovery phases. Key results Vegetation began to recover in most burned areas within the first year after fire and reached prefire levels after 10–15 years of recovery. Vegetation in areas with steep slopes (>25°) and thin soil had not recovered after 20 years, accounting for 0.3% of the total burned area. The average burn probability and fire behaviour indices of the study area decreased significantly after fire owing to lower fuel levels. Conclusions Burned areas with steep slopes and thin soil showed slower recovery rates after fire. The recovered vegetation in most burned areas still had low burn likelihood and fire behaviours 20 years post burn. Implications Artificial regeneration and fire prevention should be carried out at highly vulnerable sites for rehabilitating forest ecosystems.