The impacts of wildfires are diverse and highly variable dependent on location, habitat type, site conditions and fire severity. Wildfire impact research is however, limited across large areas of the UK presenting an issue for the creation of effective site-specific management planning in a number of areas and habitat types. To address this issue in the Brecon Beacons National Park (south Wales), research was conducted assessing post-fire: i) vegetation community composition; ii) soil physical and chemical properties; iii) ash chemical composition and toxicity. The primary conclusions from this research suggests vegetation community composition and soil physicochemical properties are able to recover relatively rapidly to long unburnt conditions (>11-years and >3-years, respectively) following wildfire events in dry heaths with shallow organic soils. The fast rates of post-fire vegetation recovery across the assessed sites are likely due to the species-poor, dwarf-shrub dominated, pre-fire conditions reducing the time required for the vegetation community to return to this low species diversity. Soil physicochemical properties showed limited impact from the fires, likely due to the high moisture retention of the surface organic soil layer having resulted in limited soil heating and depth penetration. Wider environmental concerns are raised by the ash composition, which showed remarkably high concentrations of potentially toxic substances such as, metallic elements (e.g. Fe, Mn, Pb, Zn and As) and polycyclic aromatic hydrocarbons (PAH), compared to ash from other environments and vegetation types. These conclusions pose important questions about the future of temperate heaths, the priorities of future upland management and highlight numerous areas for further research.
Vegetation fires in temperate upland heaths: environmental impacts, recovery, and management implications