Spatial distribution of the forest fires in Lower Provence:The influence of Marseille

摘要

Forest fire ignitions have been studied during summer (from June to September) from 1981 to 1997 in Bouches-du-Rh?ne (Lower Provence, France). Their locations have been crossed in a GIS with forested areas larger than 25ha. Two indices have been elaborated. The first one is based on the number of ignitions and the second elaborated from the first one defines the return period of ignitions. Both indices assess that the large city of Marseilles play an important part in the spatial distribution of the ignitions. They concentrate around the city and its surroundings a greater number of ignitions per 100ha and shorter return periods than in the rest of the area.