Enhancing the resilience of Saharan rangelands by reseeding drought tolerant native shrubs: the case of Lygos raetam in southern Tunisia

Abstract

Lygos raetam is a desert and drought-tolerant shrub native to North Africa and West Asia. Goats and camels readily graze its fruits and flowers, and it is well known for its capacity to stabilise mobile sands. This study was carried out in the communal rangelands of Dhahar, Saharan area of Southern Tunisia, to assess the impact of reseeding L. raetam on natural vegetation cover and sand mobility. A sandy rangeland site located at the border of the African Eastern Sand Sea was subjected to three management treatments: two years of rest, reseeding L. raetam, and free grazing (control). In all plots, total plant and perennial species percentage covers were determined and monitored for 5 years. Results showed that despite the improvement in the percentage of total vegetation cover recorded, the rest technique seems insufficient and inefficient in cases where vegetation degradation has reached an advanced stage. On the other hand, despite the negative effect of drought, there were considerable positive impacts of reseeding L. raetam on vegetation cover and active dune stabilization. The good establishment and survival of L. raetam seedlings may encourage rangeland managers and pastoral communities to undertake rehabilitation by reintroducing promising native Saharan species when ecosystems lose their natural resilience.