Effects of Three Different Planting Techniques on Soil Water Content, Survival, and Growth of Senegalia Seedlings on Semi-Arid Degraded Lands in Burkina Faso

Abstract

Land degradation exacerbates poverty and food shortages in Sub-Saharan Africa. Tree planting is traditionally used to restore degraded lands, but the tree species used are often poorly adapted to the local climate conditions. We evaluated the suitability and efficiency of three planting techniques (half-moon, standard plantation and zaï) in a semi-arid climate using seedlings from two native Senegalia species: Senegalia gourmaensis and Senegalia dudgeonii. A total of 116 nursery-grown seedlings were planted on degraded lands using these three planting techniques. Data on soil water content, seedling survival and growth rates were measured over 1.5 years. The effects of the planting techniques on these variables were significantly different (p < 0.001). The lowest water content was measured in the topsoil horizon (0–10 cm) and the highest in the deeper horizons (∼50 cm). At the end of the experiment, the survival rate of S. gourmaensis was 72.2% - 62.5% and 57.5% in half-moon, standard plantation and zaï, respectively. For S. dudgeonii, it was 50%, 62.5% and 47.5% in half-moon, standard plantation and zaï, respectively. There was a significant difference in height and collar diameter between S. gourmaensis and S. dudgeonii using the three planting techniques (p < 0.001). Based on our results, we recommend using the half-moon or standard plantation for Senegalia species. Senegalia species are suitable for planting in degraded land in semi-arid areas when using the appropriate planting technique.