An analysis of the effect of aspect and vegetation type on fine fuel moisture content in eucalypt forest

Abstract

The magnitude of site effect on dead fine fuel moisture content (FMC) in eucalypt forests was investigated for different fuel strata: bark, near-surface, top and profile litter. In addition, the variation across two fire seasons in litter FMC and fraction of fuel available for burning was analysed. Over different fuel strata, the aspect effect ranged from an average moisture content of ~3% in the dry forest to 11% in the moist forest, but the effect in the moist forest could also be attributed to increased vegetation cover. For the top litter (first 1 cm of litter), moisture content averaged ~4% higher than bark, and 3% lower than profile (whole) litter, differences being higher on the wetter sites. Site effects were greatest for profile and least for bark. The percentage of days that the top litter moisture content fell into categories associated with severe fire behaviour and prescribed burning availability was calculated for each site in the different forest types to facilitate discussion of fire management planning.