File:Картосхема згарищ від пожеж на Солоноозерній ділянці Чорноморського біосферного заповідника та в охоронній зоні у 2025 р.png

English: Fire scar mapping was carried out using Earth observation data based on Sentinel-2 satellite imagery (processing level L2A). The methodology was based on a stepwise algorithm for multispectral image processing and subsequent spatial analysis in the desktop GIS environment QGIS.

The main stages of the methodology included: 1. Acquisition and preprocessing of Sentinel-2 scene subsets for the defined regions of interest (ROIs). 2. Initial comparison of satellite images aimed at identifying fire scars based on visual characteristics observed in SWIR composites (Short-Wave Infrared RGB composites; band combinations 12–8–4 or 12–8–3). 3. Calculation of spectral indices and application of a multi-index threshold-based classification. 4. Generation of a binary raster layer of fire scars by computing a logical AND expression combining difference indices (RBR, dBI, dNDVI, dMSAVI2, dNDWI, dTWI, dABAI, MCSI, etc.) and, where necessary, absolute indices (NBR, NDVI, NDWI, BI, MSAVI2, ABAI, TWI), using empirically selected threshold values. 5. Vectorization of the binary raster fire-scar layer. 6. Post-processing and refinement of polygon boundaries. 7. Integration of the resulting polygons into the final vector fire-scar layer. 8. Compilation of fire-scar map schemes for a defined period (month, season, year). For map compilation, pre-prepared layouts created in the QGIS environment were used. The only variable elements within these layouts were the vector fire-scar layers and the water inundation layer corresponding to the selected period. The inundated part of water bodies was delineated by averaging normalized median values of the NDWI and TWI indices calculated separately from cloud-free Sentinel-2 scenes acquired in 2025. The corresponding polygon layer was generated using an algorithm analogous to that applied for fire-scar mapping. The layer representing the seasonally exposed part of water bodies was derived from the NDWI index calculated for a date with a high water level. The part of this layer not overlapping with the inundated water layer represents zones of seasonal drying. The Solonoozerna Section of the Black Sea Biosphere Reserve forms part of the scientific object of national heritage of Ukraine, “Natural complexes of sandy areas and associated coastal zones of the Black Sea Biosphere Reserve”. A part of the section and its adjacent protection zone is located within the Ramsar Wetland of International Importance “Yahorlytska Bay”. During 2025, the Solonoozerna Section was severely affected by fires. The total area of fire scars within the strictly protected zone reached 855.7 ha, of which 1.8 ha were affected by repeated burning. The effectively damaged area amounted to 853.9 ha, corresponding to 37.2% of the total area of the section and 46.8% of its terrestrial part. Within the protection zone, the total burned area reached 138.6 ha, including 3.2 ha affected by repeated fires. The effectively damaged area amounted to 135.4 ha, or 36.5% of the protection zone area. A portion of the fire scars also occurred within the Ramsar Wetland of International Importance “Yahorlytska Bay”, where the total fire-affected area reached 192.4 ha, including 142.1 ha within the strictly protected zone and 50.3 ha within the protection zone of the Black Sea Biosphere Reserve. Areas that remained largely unaffected were mainly those parts of the section and the protection zone separated by systems of lakes and channels that hindered the spread of fire. In terms of fire impact extent, 2025 was second only to 2022, when a significant part of the Solonoozerna Section and the adjacent protection zone was burned.

As a result of these large-scale fires, rare natural complexes were damaged, represented by a mosaic of sandy steppe, meadows, small groves, wetland and salt-marsh vegetation surrounding lakes and the bay. The main factor driving fire occurrence within the protected area and its protection zone remains the consequences of military activities in the region.

English: The map shows fire scars identified in 2025 within the Solonoozerna Section of the Black Sea Biosphere Reserve of the National Academy of Sciences of Ukraine and its protection zone. Burned areas are delineated based on Sentinel-2 satellite imagery, while water bodies are classified into inundated and seasonally exposed parts. The map also indicates the boundary of the Ramsar wetland of international importance “Yahorlytska Bay”