Understanding how multiple disturbances affect species population structure is crucial for designing a better conservation strategy of threatened species. In this paper, we assessed the disturbance patterns and evaluated their effects on the population structure of Afzelia africana, in two different bioclimatic zones of the Republic of Benin. The main disturbances in the studied area included branch pruning and debarking. Individuals of medium size (20-40 cm) were mostly pruned and debarked. The percentages of pruning and debarking were similar at population level across the two studied bioclimatic zones (t = −0.04, p = 0.96; t = 0.73, p = 0.48). Examining this at individual level, pruning was similar but debarking was higher in the Sudanian zone (12.14 ± 0.93%) than in the Sudano-Guinean zone (7.44 ± 0.88) (W = 40859, p < 0.001). Population structure was bell-shaped in the Sudanian zone regardless of the disturbance level. In contrast, in the Sudano-Guinean zone, mildly disturbed populations showed an inverse J-shaped structure, whereas those highly disturbed were bell-shaped. This underlined the climatic (dryness) and disturbance effects on the establishment and recruitment of small trees into the next life stage in tropical savanna ecosystems. Good regeneration pattern and the largest individuals were found within the protected areas, demonstrating the prominent role of protected areas for the species conservation. Therefore, we suggested that conservation efforts should be extended to populations outside the protected areas. Forestry department should establish firebreaks networks to protect small individuals and facilitate their recruitment, as well as the regulation and enforcement should be improved on the sustainable use of the species.

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Haematostaphis barteri Hook.f. is an endemic plant species with a high economic potential that mostly grows on rocky soils in the Sudanian zone from Ghana to Sudan. In Bénin, the species is found only around the commune of Natitingou, but there is little knowledge on its uses by the local populations and how these uses potentially affect its conservation status. This study aimed to evaluate the vulnerability of H. barteri in its natural range in Benin, based on the assessment of its indigenous uses and its population inventory. An ethnobotanical survey was conducted in eight villages of the commune of Natitingou from eighty people belonging to the Bètammaribè and Waaba ethnic groups, to identify their knowledge and usage of the species. The species population inventory was also carried out to estimate the frequency and density of H. barteri populations. The species' vulnerability score was determined using results from the ethnobotanical survey, population inventory and information in the literature. Rural populations in Natitingou use H. barteri mainly for food (100% of interviewees), traditional medicine (76.3%) and wood fuel (37.5%). Most of the respondents (91.3%) usually harvest immature fruits so as to preserve them, both for their consumption and for commercialization. Twentynine populations of H. barteri were identified with densities averaging 46.6 adult individuals per hectare and a regeneration of 9.7 individuals per hectare. The average vulnerability score for H. barteri was estimated at 2.4 on a scale of 1 (not vulnerable) to 3 (highly vulnerable). H. barteri is thus a vulnerable species that deserves to be included in Benin's list of endangered species.