The recovery of Sphagnum capillifolium following exposure to temperatures of simulated moorland fires: a glasshouse experiment

Background: In the UK, government legislation allows the use of prescribed fire in peatlands for land management purposes. The use of fire, however, remains controversial, partly because of a distinct lack of data on the response of key peatland species to fire. Sphagnum species are key components of peatland ecosystems, yet a fundamental knowledge gap in the debate is the response of Sphagnum species to fire. Aims: To determine if a widespread species (Sphagnum capillifolium) has the ability to recover from exposure to high temperatures, analogous to those recorded in managed peatland fires. Methods: Samples of S. capillifolium were exposed to a range of temperature treatments. Recovery was monitored using chlorophyll fluorescence, CO2 exchange and physical damage and new growth assessed. Results: We found that the degree of recovery of S. capillifolium was related to the temperature treatment, post-treatment environmental conditions and pre-treatment stem moisture content. The slowest recovery was found when samples were heated to 400°C for 30 s. Conclusions: Our results demonstrate that S. capillifolium has the ability to recover following exposure to the temperatures experienced in prescribed fire, provided that at least some living material remains. Our results suggest that prescribed burning in the spring may allow for a quicker recovery than autumnal fires.