Spatial structure of <i>Xylopia aethiopica</i> (Dunal) A. Rich., in the GuineoCongolean zone of Benin (West Africa)

Xylopia aethiopica is a spice widely consumed in sub-Saharan Africa for the medicinal virtues of its fruits and seeds, whose distribution in its natural habitat is compromised by anthropic pressure. The aim of this study was to characterize the spatial distribution of Xylopia aethiopica plants and the possible interactions (attraction, independence, repulsion) that exist between them under the direct or indirect influence of the environment in which they grow. Phytosociological surveys were carried out in habitats hosting Xylopia aethiopica in the Guineo-Congolean zone of Benin. The geographical coordinates of adult plants and seedling individuals of Xylopia aethiopica were collected in 50 m x 200 m rectangular plots. The results of the univariate analysis showed that the spatial distribution of adult plants and seedlings was significantly aggregated in the fields. However, a random distribution trend was noted among seedling individuals, due to anthropogenic environmental influences. In the semi-deciduous dense forest, adult plants were significantly aggregated, with a tendency towards random distribution over certain distances, whereas seedling individuals had a significant exclusively aggregated distribution. In the gallery forest, both adult plants and young individuals were significant aggregated. Bivariate analyses showed that in the fields and the semi-deciduous dense forest, spatial associations were positive (attraction) and there was a strong independence of seedling individuals from adult plants over certain distances. Moreover, spatial associations between adult plants and seedling individuals in gallery forest were exclusively positive (attraction). The results of this study could be useful for policies aimed at the sustainable conservation of vulnerable plant species in Benin.