Geospatial assessment of above-ground biomass degradation in forest habitats of the “Svyati Hory” National Nature Park due to armed conflict-related wildfires (2022–2024)

This study develops a method for assessing above-ground biomass (AGB) in forest habitats of the “Svyati Hory” National Nature Park and quantifies its degradation caused by armed conflict-related wildfires in 2022–2024. A multisensor approach integrating Sentinel-1 and Sentinel-2 data, the Copernicus GLO-30 DEM and GEDI LiDAR measurements was applied via a Random Forest regression model calibrated with forest inventory records. Comparative analysis confirmed the superiority of the 10 m spatial scale (R2 = 0.575) over 20 m and 30 m resolutions for fragmented mosaic landscapes. The model demonstrated strong predictive performance (RMSE 15.3–17.7 Mg/ha), enabling rapid biomass updates when field surveys are hindered by limited accessibility to the area. Results indicate that the park’s total baseline AGB was 14.22 million tonnes across 37.1 thousand hectares. Burn scar mapping and spatial overlay analysis revealed a total loss of 4.66 million tonnes of biomass over 11.96 thousand hectares. The highest losses occurred in Sarmatic steppe pine forests, which lost 68.2% of their biomass. The relict chalk pine forests (Pinus sylvestris var. cretacea) were likewise severely affected, losing 36.6% of their area, thereby threatening the natural regeneration of this endemic population.