Un approccio probabilistico alla valutazione della stabilità dei versanti forestali=A probabilistic approach to the evaluation of forested hillslopes stability

Vegetation, as well known, can affect slope stability in different ways, mainly by the root system, which mechanically reinforces the soil and reduces soil moisture content. Root reinforcement is generally expressed in terms of additional root cohesion, which is directly related to the number of roots crossing the margin of a sliding soil volume and to the force mobilized by each root element subjected to tension during the sliding phenomenon. Although in the last decades, several studies have been conducted on such topic and a deep comprehension of the process has been reached, however, the spatial variability of the root reinforcement and its dependence from the forest stand characteristics (species, density, DBH, etc.), remains open points. To introduce such points into process-based models of slope stability, we have developed a method able to account for the variability of root reinforcement and its spatial distribution as function of the characteristics of forest stands. In this paper, we present preliminary results of its application to a small headwater catchment.