Impact of land use on the regeneration of Senegalia macrostachya in Burkina Faso, West Africa

Abstract

Senegalia macrostachya is a wild crop with socioeconomic potentials across West Africa. This study aims to assess the impact of land use on the regeneration patterns of the species according to climate zones in Burkina Faso. A total of 193 rectangular plots were sampled in farmlands, fallows and protected areas across the Sudano-sahelian and Sudanian climate zones. The size and population parameters of juveniles, as well as the mechanisms of regeneration were assessed and compared among land use types, climate zones, and regeneration mechanisms using ANOVA followed by Tukey's HSD and a chi-square test. Density of juveniles was significantly higher (p < 0.001) in protected areas (223.93 ± 122.45 individuals per ha) than in fallows (106.79 ± 57.22) and farmlands (64.39 ± 57.57). The height of juveniles was significantly higher (p < 0.001) in the Sudanian zone (0.70 ± 0.44 m) than in the Sudano-sahelian zone (0.42 ± 0.15 m). The largest collar diameter (14.61 ± 7.23 mm) observed in the farmlands varied significantly between climate zones. The distribution of the diameter size class revealed stable juvenile populations. Diameter classes of less than 1 cm exhibited the highest densities. As far as the regeneration mechanism is considered, Senegalia macrostachya regenerated mainly by sprouting stumps in farmlands (84.82 %) and fallows (47.72 %) and by seedlings (65.58 %) and suckering (27.53 %) in protected areas. The results prove that Senegalia macrostachya has a good natural regeneration potential that can be promoted for sustainable management and conservation of the species in agroforestry systems. The strategy could be assisted natural regeneration, which is low cost and easy to practice by local populations.

Keywords

• Agroforestry system
• Senegalia macrostachya
• Natural regeneration
• Wild crop
• Land use type
• Climate gradient