MORPHOLOGICAL AND STRUCTURAL CHARACTERIZATION OF LOPHIRA LANCEOLATA POPULATIONS IN BENIN (WEST AFRICA)

Résumé

Knowledge of a species population’s structure is a prerequisite for any management program. The objective of this study is to make a typology of the populations of Lophira lanceolata Tiegh. ex Keay (Ochnaceae) in Benin on the basis of its morphometric features and to characterize homogeneous groups retained. Thus a floristic inventory was carried out in 70 plots (50m x 50m) installed in the species' presence populations throughout the country. The diameter at breast height (DBH), the total height (Ht), the diameter of the crown (Dm), leaf length (Lmf) and leaf width (lmf) were measured on each individual of Lophira lanceolata. The hierarchical classification of the 70 plots on the basis of the measured traits and the positioning of plots in relation to these traits on the factorial plan allowed to distinguish four (04) homogeneous groups among which three presented good discrimination: Bassila populations composed of broad-leaved and long-leaved trees, populations of Kandi made up of individuals with high height and those with large crowns and populations of Toucountouna_Ouidah with high density per hectare and made up of trees with large basal area. Populations of Bassila, N'dali_Natitingou had an inverted J-structure while that of Kandi had a bell-shaped distribution centered on the 30-40 cm diameter class. This study suggests that Lophira lanceolata is included in national conservation strategies for endangered species.