Development of a model system to predict wildfire behaviour in pine plantations

Abstract

Summary We describe the development of a model system to predict fire behaviour over the full range of potential fire behaviour in the various types of fuel complexes found in exotic pine plantations in relation to environmental conditions. The proposed system integrates a series of sub-models describing surface fire characteristics and crown fire potential (e.g. onset of crowning, type of crown fire and associated rate of spread). The main inputs are wind speed, fine dead fuel moisture content and fuel complex structure (surface fuel bed characteristics, canopy base height and canopy bulk density). The detail with which the model system treats surface and crown fire behaviour allows users to quantify stand ‘flammability’ with stand age for particular silvicultural prescriptions. The application of the model to a case study of thinning treatments in a radiata pine plantation in Victoria is presented. The results highlight the complex interactions that take place between fire behaviour and attendant fuel and weather conditions. Structural changes in the fuel complex introduced by the treatments altered fire behaviour, but no definite reduction and or increase in rate of fire spread was identified. The results illustrate the role that simulation models can play in support of silvicultural and fuel management decision making.