Wildland Urban Interface: mapping and wildfire risk assessment

The Rural Urban Interfaces (RUI), are those areas in which vegetation and houses are in contact or intermingled. Vegetation constitutes the prerequisite for wildfire propagation and, given the high number of values exposed to risk, it is in RUI that the worst consequences of wildfires are recorded and that a wildfire risk assessment is particularly important. The present thesis is divided into two parts:- In the first one RUI are mapped and classified, and a characterization of the relation RUI – fire regime is performed. The study uses three operational definition of RUI and shows how the RUI area largely depends on the adopted definition. Although the maps obtained using various methodologies differs in identifying portions of the territory as RUI, all methodologies consistently recognise that inside RUI the ignition density is higher and the burned areas are smaller than elsewhere. A case study of diachronic mapping shows the utility of RUI mapping and classification for describing the evolution of RUI phenomenon.- In the second part the maps resulting from the development and application of three models for wildfire risk assessment in RUI are presented. In particular, aside an application of a classical overlay mapping methodology taking into account the principal risk factors, we develop and apply other two methodologies: a Multicriteria approach with Analytic Hierarchy Process and a Multisimulation approach using wildfire simulators for quantifying house exposure.