Aleppo pine (Pinus halepensis Mill.) and Calabrian pine (Pinus brutia Ten) forests cover approximately 3 500 000 ha in the Mediterranean Basin, mostly at low elevations (less than 500 m) and along the coastline. These forests are particularly prone to fires and represent approximately 1/3 of the total annual burned area in the Mediterranean Basin The dense broadleaved-evergreen shrub understory (known as “maquis”) below the live crown fuel layer creates ladder fuels that facilitate fire transition from the forest ground to the canopy layer. These conifer species grow under arid conditions, thus resulting in increased fire frequency and intensity.
Fires spreading in conifer fuels are very complex phenomena. They usually occur under extreme fire weather conditions, resulting in erratic and dangerous crown fire behavior. After crowning, fires have been observed to increase their rate of spread, intensity and spotting activity. Crown fires are virtually impossible to control by direct action. They are also responsible for the largest proportion of the overall area burned in large fires in coniferous forests, worldwide. The importance of crown fire behavior prediction in assessing fire potential has made it a prerequisite for evaluating the effectiveness of fuel management treatments during fire prevention planning. Fire behavior models implemented in fire management decision support systems require accurate descriptions of fuel complex characteristics. Until recently, fuel complex characterization has been limited to surface fuel beds, due to the restricted applicability of fire behavior simulation models only to surface fuels. The development of fire behavior models and systems designed to predict crown fire behavior made necessary the measurement of canopy and shrub understory fuel data.
All these have led to the development of a variety of alternative research efforts to implement Fire Management Systems which can be useful in fuel management and fire suppression planning.