Effects of slope and fuel load of Pinus halepensis needles beds on fire behaviour: models determined in the laboratory

Abstract

Fire behaviour has been studied on an laboratory device in fuel beds of Pinus halepensis needles. The effect of slope (seven levels:-30º, -20º, -10º, 0º, +10º, +20º, +30º) and fuel load (three levels: 0.4, 0.8, 1.2 kg · m-2). The experiments have been conducted on homogeneous ovendried neddles. Fire spreads steadily with all fuel loads and slopes between -30º and +10º and also at +20º with 0,4 kg · m-2. For fuel loads of 0,4 y 0,8 kg · m-2, rate of weight loss is lenarly related to rate of spread (the relation is significant); with 1,2 kg · m-2. the relation is weaker. Remaining fuel ratio increases when slope increases from -30º to 0º and decreases when fuel load increases. Two other parameters (maximum temperatures and areas bewteen temperature-time curve and istherm 60º C) depend on slope and increase with fuel load. This work takes place in a more global study of INIA and INRA to elaborate models to predict fire behaviour.