Different responses of Pinus sylvestris L. and Larix decidua Mill. to forest fire in Central England (UK)

Abstract

The United Kingdom (UK) is facing a growing threat due to the increasing frequency of fires attributed to anthropic pressures and activities. This research analysed the impact of a human-induced 2018 wildfire in a mixed woodland of Pinus sylvestris L. and Larix decidua Mill. in The Roaches Nature Reserve (central England). Through a multidisciplinary approach integrating remote sensing, forest surveys, dendrochronology and soil analysis, we compared burned and non-burned (control) trees to assess the eco-physiological responses of two plant species. Remote sensing supported both the strategic planning of field activities and the characterization of vegetation dynamics affected by fire under pre- and post-fire trajectories, while dendrochronological and soil analyses provided crucial information on post-fire forest dynamics. Results showed that, although both species demonstrated good resistance to the immediate impact of the fire, their responses in terms of resilience and recovery were different in the medium-term (5 years). P. sylvestris (Scots pine) showed good resilience and recovery capacity, with surviving trees showing improved growth within five years, though full recovery may still require several years. In contrast, L. decidua (European larch), although a fire-adapted species, experienced nearly total mortality within three years, most likely because of secondary stressors, such as a pathogen outbreak, which potentially compromised its resilience and recovery capacity in the medium-term. According to our results, climate does not seem to have played a determining role in larch tree mortality, as weather conditions were favourable for both species over the years. Likewise, soil properties showed no variation that could decisively influence survival dynamics. This study highlights the importance of understanding species-specific responses to fire and potential secondary stress factors, emphasizing the need to implement effective management strategies for prevention and management of mixed forests in regions where fire incidence is emerging.