Land restoration by fodder shrubs in a semi-arid agro-pastoral area of Morocco. Effects on soils

The present study assesses the effects of Atriplex nummularia Lindl. growth on soil chemical properties in a semi-arid area. The area is located in the Marrakech province (Morocco), in a degraded agropastoral region subjected to soil restoration actions based on fodder shrub plantations.Three plantations of different age (1995, 2000, 2001), conducted in three different sites, were investigated. In each site, three plots with different degree of plant development (Good, Medium, Poor), were chosen. Three under-canopy (Uc) and three between-plants (Bp) minipits were sampled (0–10 cm and 10–20 cm) and analysed in each plot, for a total number of 54 minipits. Statistic analysis was carried out to check the significance of the observed Uc–Bp average differences.A significant increase under canopy was observed in soil Sodium Adsorption Ratio (SAR; + 139%) and OC (+ 32%) in the top layer (0–10 cm). The overall effects of the plantations on soil quality are discussed.

► Atriplex nummularia plantations determined both positive and negative impacts on semi-arid soils in Morocco.
► Both soil organic carbon and alkalinity (SAR) significantly increased in a decade.
► Suitable strategies would be needed to ensure the long term sustainability of the artificial sylvo-pastoral systems based on A. nummularia.