High-Resolution Burn Severity Mapping in Mixed Coniferous and Deciduous Forests: The Case of the 2025 Ilindentsi Wildfire

This study investigates the ecological impact and burn severity of the August 2025 Ilindentsi wildfire in the Pirin Mountain foothills, Bulgaria, using high-resolution Sentinel-2 multi-spectral imagery and Google Earth Engine. In the last decades accelerating regional warming trends – reaching a peak national average temperature of 2.1°C above climate norms in 2024 – record-breaking heat and moisture deficits in 2025 created "explosive" fuel conditions for the forest fire out breaks along the SW Bulgaria. Utilizing a triple-window temporal approach (January dormancy, June phenological peak, and July pre-fire baseline), the research successfully distinguished between coniferous and broadleaf stands to quantify fire interaction across 3,927.26 hectares. The analysis revealed a significant disparity in fire vulnerability: coniferous stands were the primary drivers of high-intensity fire, with 29.5% of their area experiencing high to moderate-high severity (Codes 24 and 25). In contrast, broadleaf stands showed higher resilience, with 56.6% of their footprint experiencing only low-intensity surface fires. The study implemented a specialized 12-element coding scheme and a three-tier management priority system to guide surgical ecological restoration. This system prioritizes the 545.25 hectares of high-severity coniferous forest (Code 25) for immediate forestry and nature-based restoration solutions. Furthermore, 373.58 hectares of moderate-high severity coniferous forest (Code 24) are designated for intensive sanitary monitoring against bark beetle outbreaks. These findings demonstrate that high-fidelity remote sensing can effectively bridge the gap between rapid emergency response and long-term sustainable forest management in complex landscapes.