Dendrometric structure and spatial distribution of Pterocarpus erinaceus Poir. in three savannah types stands in Côte d'Ivoire

In the savannahs of West Africa, the availability of species with high socio-economic value, such as Pterocarpus erinaceus, depends on ecological characteristics and anthropogenic activities. This study examines the abundance, demographic structure, and spatial organisation of P. erinaceus in different environments. A set of data was collected, including eco-edaphic and dendrometric parameters, and GPS coordinates. Site degradation levels were qualitatively inferred from field observations and site conservation status. Abundance was evaluated using regeneration density and the density of trees with DBH > 5 cm. Individuals were grouped into 5 cm DBH classes to analyse demographic structure using ecological indices. Spatial organisation was studied using univariate (g11(r)) and bivariate (O12(r)) spatial functions, distinguishing juveniles (5 < DBH < 10 cm), non-exploitable adults (10 ≤ DBH < 35 cm), and exploitable adults (DBH ≥ 35 cm). Results show that low anthropogenic pressure and favourable environmental conditions promote high abundance and stable demographic structures, marked by active recruitment. Conversely, disturbances on poor soils limit regeneration and recruitment. The interaction between soil infertility, livestock pressure, and human activity causes population instability and hampers sustainability. The study highlights the importance of incorporating local eco-edaphic contexts into adaptive conservation strategies considering spatial and demographic dynamics.