“…In Mediterranean areas, erosion is particularly pronounced both in the semiarid regions (200-300 mm year −1 ), and in the sub-humid ones (900-1500 mm year −1 ) and the strong variability in annual precipitation with frequent events of extreme rainfalls may result in time-transgressive susceptibilities of regional erosion (after Boardman and Favis-Mortlock, 2001). Many studies were made on erosion simulations and on ecosystem responses to future climate changes (e.g., Newson and Lewin, 1991;Easterling et al, 2000;Yang et al, 2003;Nearing et al, 2005;Michael et al, 2005;Phillips et al, 2006;Quilbe et al, 2007), but few researches allowed to quantify the effects of past climate variability on the dynamics of geomorphological processes (Rumsby, 2001;Diodato, 2006;Foster et al, 2008), while they study episodic impacts of extreme rainfalls (e.g., Gomez et al, 1997;Hooke and Mant, 2000;Coppus and Imeson, 2002;Martínez-Casasnovas et al, 2002;Mul et al, 2008). Other researches are mainly based on plot covers and soil types and they cannot be scaled up to catchment scales (Dickinson and Collins, 2007).…”