3 - "Cartographie de la vulnérabilité des territoires face aux feux de forêt : évaluation multicritères participative"

The Mediterranean region is routinely affected by forest fires, with adverse consequences on ecological, infrastructural, and socioeconomic assets. However, few studies tackle the issue of characterizing territorial vulnerability with respect to an increasing wildfire risk. We focus on Southern France and perform an assessment of fire risk and vulnerability using a spatial multicriteria decision analysis (MCDA) method where expert judgements are gathered through a participative approach. We apply a conceptualisation of risk and vulnerability from the hazards literature adapted to the case of forest disturbances, making a clear distinction between several subcomponents - hazard, exposure, sensitivity and adaptive capacity - which we assess for three categories of assets – people, infrastructure and ecosystems. We develop a series of spatialised indicators using ecological, land-use and sociodemographic data, which we aggregate using Saaty’s Analytical Hierarchy Process. Results show expert judgements on indicators’ relative importance to be highly consistent. They reveal significant differences in indicators’ perceived contribution to risk and vulnerability and enable appraising the contribution of sociodemographic factors, often overlooked in the literature. Map results reveal differences in spatial patterns across both vulnerability subcomponents and exposed assets. They help identify primary and secondary vulnerability hotspots, and comparisons with individual indicator maps help understand how underlying determinants affect vulnerability and risk. Confrontation with a hazard map obtained with a wildfire simulation model highlights both discrepancies and commonalities in spatial patterns for vulnerability and hazard. Consideration of multiple subcomponents of risk and vulnerability may help local decision makers prioritize how and where measures should be implemented, while the use of MCDA favours experience and knowledge sharing and among stakeholders while providing a basis of discussion