Pastoral and woodcutting activities driveCedrus atlanticaMediterranean forest structure in the Moroccan Middle Atlas

Abstract

Scientists are now realizing how widespread human activities have been in ecosystems and the need to take them into account to understand their functioning (Willis et al. 2004), especially in the Mediterranean basin. In this anciently occupied region, humans have tapped the ecosystems for resources for millennia, modifying ecosystem characteristics (Grove and Rackham 2001, Quézel and Médail 2003) while maintaining high levels of biodiversity (Blondel 2006). However, this biodiversity is threatened by the speed of both climate and anthropogenic changes (Quézel and Médail 2003). On the northern shore, biodiversity is menaced by woody encroachment and habitat fragmentation (Scarascia-Mugnozza et al. 2000). Conversely, on the southern shore, demand for natural resources is ever growing and human activities inside forests are intensifying (Scarascia-Mugnozza et al. 2000). In this context, both researchers and managers critically lack knowledge about the impacts of human disturbances on Mediterranean forests (Scarascia-Mugnozza et al. 2000) and especially their combined effects (Wisdom et al. 2006). This lack of knowledge is especially true on the southern shore, where empirical data is scarce. Understanding these forests' functioning could (1) give insights considering pressure levels necessary to maintain biodiversity in the

Are Cedrus atlantica forests in the Rif Mountains of Morocco heading towards local extinction?

“…yr AD from the Jbel Khesana, most probably as a consequence of loggings carried out by the Spanish government (Ajbilou et al, 2003; Araque and Garrido, 2015). A further regeneration could have been ultimately unachievable because of the high incidence of the subsequent human activities in the area, including logging, slash-and-burn farming (‘sbir’) and overgrazing (Coudel et al, 2016; Rejdali, 2004; Taiqui, 2005), which triggered a strong soil erosion (Moore et al, 1998), along with increasing temperatures and aridity. This enhanced soil erosion is also pointed out by the high levels of PC1 and PC4, related to the increase of sediments coming from the slope bedrock (marls) weathering (Figure 7).…”

“…Model simulations indicate an upward shift of the lower limit of their range in the Rif Mountains by about 200 m (Cheddadi et al, 2017). Recent decline in these mountains, however, is considered to have been induced by human activities, mainly cropping, cutting and overgrazing (Ajbilou et al, 2003; Benabid, 1985; Coudel et al, 2016; Grovel, 1996; Hamelin and Nwankwo, 2013; Moore et al, 1998; Rejdali, 2004). Disentangling the impact of each factor on landscape is not an easy task, although essential to take the appropriate managing measures to ensure the persistence of the modern populations (Allen et al, 2010; El-Baha et al, 2010; IRES, 2010; Vegas-Vilarrúbia et al, 2011).…”