Studies on Fire in Scottish Heathland Communities: I. Fire Characteristics

Publisher Website
Google Scholar
Abstract
Previous studies of heath fires produced widely differing values for temperatures reached. Methods are described of characterizing heath fires using measurements of temperature, rate of spread, fuel energy and fire intensity. Measurements taken in fires set in heath stands of different types and ages suggest that temperature and fire intensity increase with stand age up to the late mature phase of Calluna (i.e., 20-25 yr old). Thereafter, temperature and intensity decline but the variability of temperature increases. Temperature at the ground surface was often was high or higher than the canopy temperature, but at 1 cm beneath the soil surface the temperature remained below 100.degree. C. Trends in temperature were related mainly to vegetation structure and to the amount and distribution of fuel in the stand. Environmental variables are considered to be of secondary importance as long as they remain within normal limits. Fire severity was positively correlated with fire width, a factor which has important management implications. A regression of maximum canopy temperature against vegetation height, fire width and wind speed provided good estimates of results from previous studies, but emphasized the unrepresentative nature of some past recordings.