Aperçu de la végétation de quelques inselbergs du Bénin

Six inselbergs of Benin have been studied in four localities. This study presents the results of 123 phytosociological "relevés". A total number of 285 plant species have been gathered belonging to 77 families, of which Poaceae (34 species) and Fabaceae (32 species) are the most representative. The 285 plant species identified have been classified in seven groups according to the vegetation types. The analysis of life-form spectra has revealed the abundance of therophytes (38.2% and 36.5%) and phanerophytes (39. 7% and 37.2%). The grasslands are dominated by annual species. The number of therophytes increases from south to north; this could be due to decrease of average annual precipitation. The phytogeographical spectrum of species have revealed the abundance of sudano-zambezian elements (21.4% and 23.9%) and African pluriregional elements (21.4% and 21.6%). No endemic species have been noted among the 285 species. The two phanerophytes most frequently encountered and restricted to the inselbergs are Hymenodictyon floribundum and Ficus abutilifolia. The most characteristical species of dry grasslands is Afrotrilepis pilosa. Inselberg vegetation is characterized by its homogeneousness due to harsh environmental conditions.SCOPUS: re.j