Factors affecting severity of wildfires in Scottish heathlands and blanket bogs

• DOI: 10.1016/j.scitotenv.2024.172746
• Publication Date: 2024-04-26T16:06:50Z
• Authors: Noemi A.L. Naszar...; Thomas Cornulier; Sarah J. Woodin; Louise C. Ross; Alison J. Hester; Robin J. Pakeman
• Keywords: Scotland; Wetlands; Weather; Ecosystem; Wildfires; Environmental Monitoring

Temperate heathlands and blanket bogs are globally rare face growing wildfire threats. Ecosystem impacts differ between low high severity fires, where reflects immediate fuel consumption. This study assessed factors influencing fire in Scottish bogs, including the efficacy of Canadian Fire Weather Index System (CFWIS). Using remote sensing, we measured differenced Normalised Burn Ratio at 92 sites from 2015 to 2021. We used Generalised Additive Mixed Models investigate impact topography, habitat wetness, CFWIS components 30-day weather on severity. Dry heath exhibited higher than wet bog, slope, elevation south facing aspect were positively correlated effects less clear due data scale differences, yet still indicated weather's significant role Rainfall had an increasingly negative effect approximately 15 days before fire, whilst temperature positive effect. Vapour Pressure Deficit (VPD) was variable with highest explanatory value, predicted better any component. The best-explained model (R2 = 0.25) incorporated wetness wind VPD day fire. Drought Code (DC), predicting organic matter flammability ≥10 cm soil depth, component predictive across habitats. Our findings suggest that wildfires typically characterised by severity, but warmer, drier may increase risk severe, smouldering fires which threaten peatland carbon stores.