Measuring suppression : quantifying reductions in burn probability from initial attack

Abstract

Rapid suppression, or initial attack (IA), is the primary method of managing new fires, with relatively low costs and high containment rates. Factors contributing to containment are well understood, but consequences for the landscape-level distribution of fire risk are not. This research introduces a method of assessing IA impacts using spatially-explicit burn probability (BP) analysis, and applies it to a study area in Kootenay National Park. BP is assessed with and without the influence of suppression by combining the Burn-P3 model with a stochastic probability of containment algorithm. Results indicate IA impacts are spatially heterogeneous. Suppression was most effective in recently burned areas, whereas mature, contiguous fuels moderated its influence. IA was least effective in the management zone where natural fire is not permitted, suggesting supplementary tactics may be appropriate. Managers can use this method to compare emergent, fine-scale consequences of fire management policy and increase long-term management effectiveness.