Morocco possesses a rich and varied flora, owing partly to its great diversity of relief and landscapes. However, advancing erosion and processes of desertification, combined with the development of human activities, are damaging this biodiversity. One of the representative species of this flora, the cypress Cupressus atlantica, is experiencing year by year a decrease in its biomass production and the surface areas it occupies. This species contributes to efforts to control erosion and degradation of forest soils. But it is highly sought after by local communities particularly for the quality of its wood. In addition, the young shoots are subjected to overgrazing (by sheep) which hinders the species' natural regeneration. Replanting operations have been undertaken, but have proved largely unsuccessful, with nearly 70 % of the young saplings planted dying after the first year.
To counter the threat hanging over this species, a research programme was set up in 2003, jointly between the Cadi Ayyad University of Marrakech, the High Atlas Regional Forestry Directorate and scientists from IRD research unit UR 040 (1). The IRD researchers proposed an original ecological approach, founded on the study of interactions between the cypress, the shrubby plantslavender and thymeassociated with them and the soil microflora, in order to define new practices for cypress replanting schemes in the Moroccan Atlas.
Cypress develops symbiotically with soil micro-fungi, arbuscular mycorrhizal fungi (2). This association yields mutual benefits, the plant providing sugars for the fungi which in return helps provide the tree's supply of water and mineral salts, mainly of nitrogen and phosphorus. In controlled mycorrhization glasshouse experiments, the researchers inoculated strains of these fungi, sampled from the study zones in the Moroccan High Atlas, into young nursery plants. There resulted a distinct improvement in the development of these young cypress with in
Contact: Marie Guillaume-Signoret
Institut de Recherche Pour le Dveloppement