Quantitative charcoal reflectance measurements better link to regrowth potential than ground-based fire-severity assessments following a recent heathland wildfire at Carn Brea, Cornwall, UK

Abstract

Charcoal has recently been suggested to retain information about the fire that generated it. When looked at under a microscope, charcoals formed by different aspects of fire behaviour indicate different ability to reflect the amount of light when studied using the appropriate technique. It has been suggested that this method, charcoal reflectance (Ro), might be able to provide a quantitative fire severity metric that can be used in conjunction with or instead of standard qualitative fire severity scores. We studied charcoals from a recent heathland wildfire in Carn Brea, Cornwall, UK, and assessed whether charcoal reflectance (Ro) can be linked to standard qualitative fire severity scores for the burned area. We found that charcoal reflectance was greater at sites along the burned area that had been scored as having a higher qualitative fire severity. However, there were clear instances where the quantitative charcoal reflectance measurements were able to better indicate damage and regrowth potential than qualitative scoring alone. We suggest measuring the reflectance of charcoals may not only be able to provide quantitative information about the spatial distribution of heat across a burned area post fire but that this approach is able to provide improvement to fire severity assessment approaches.