POST-FIRE ASSESSMENT OF A RAISED BOG IN CENTRAL IRELAND

Peatlands cover 20% of Ireland, yet only a small proportion of Irish peatlands are in pristine condition as anthropogenic activity such as mechanical cutting and drainage, have already resulted in a 47% loss of habitats (IPCC Peatland Sites Database, 2009); prolonged drainage is also thought to make these degraded peatlands more vulnerable to fire. All Saints Bog, Co. Offaly, central Ireland, is a raised bog that has been subject to drainage, and is considered a conservation priority due to the rare patch of bog woodland on the site. However, drainage from former industrial turf cutting has increased the fire risk of the bog. This increase in fire risk could be detrimental to the ecology and biodiversity of this priority habitat. In order to minimize the impact of fires it is important to understand the nature of fires occurring on these bogs. Yet the relationship between fire intensity and severity is poorly understood for peatlands. A fire in 2013 burned a section of the uncut, drained bog, as well as part of the bog woodland habitat, providing the opportunity to assess the ecological impact of fire on a drained peatland. We have undertaken a detailed post-fire severity survey, which revealed a range of burn severities from scorched to high severity across the bog. Surface charcoal samples were taken from seventeen sites across a range of severities and studied under oil using reflectance microscopy. The study of charcoals by reflected-light is an underutilized technique that can provide estimates of charring temperature for wildfire-derived charcoal (McParland et al., 2009). Charcoals were identified, and resulting reflectance data were grouped, according to four fuel types: bryophytes, peat (ground fuels), angiosperm wood (heather shrub layer) and gymnosperm wood (trees). Our results suggest that the vegetation imparted a strong influence on both the charring temperatures and the burn severity at All Saints Bog. These data can be used to help understand the impact of fires on this vulnerable habitat.