Modelling socio-economic drivers of forest fires in the Mediterranean Europe

Abstract

Forest fires in the Mediterranean Europe are mostly related to human activities. More than 90% of fires are originated from either deliberate or involuntary causes. Socio-economic changes occurring in Europe in the last decades (e.g., abandonment of agricultural lands, depopulation of rural areas, changes in agriculture and forestry policies, etc.) have driven landscape transformations affecting fire risk levels through processes like e.g., increase of unmanaged lands, dead and live biomass accumulation, new uses of the forest and natural lands. In this work we analysed and attempted modelling the influence of socio-economic factors and their change over time on forest fire occurrence in the Mediterranean Europe (EU-Med). Three 6-year time periods were considered (1988-1993, 1998-2003, 2004-2009). Fire data was extracted from the European Fire database of the European Forest Fire Information System (EFFIS). Our analysis was performed in the most fire-affected area of Europe, the European Mediterranean region covered by Portugal, Spain, France, Italy and Greece. Fire data were analysed according to their main fire cause (accident-negligence and deliberate). Both, fires and socio-economic variables, which represent anthropogenic factors related to fire activity, were mapped on a 10 km x10 km grid. Models of forest fire density were derived separately for each period and per cause category using ordinal regression statistical methods. The best predictors by period and fire cause category were assessed and differences between time periods analysed. Our result show that the variable wildland-urban interface (WUI) is related to higher ratings of fire density. This result was consistent for all periods and for the two type of fire cause analysed in our study. The overall fit of the models was 40-50%.for accident-negligence and 50% deliberated caused fires. Despite the relatively homogeneous socio-economic characteristics of the Mediterranean Europe, differences are found at regional level and by fire cause category. The anthropogenic drivers of forest fires are a challenging yet fundamental factor to understand and model the European Mediterranean fire environment.