Pollen-rain-vegetation relationships along a forest-savanna transect in southeastern Cameroon

A. Vincens (1) , M.A. Dubois (2) , Bernard Guillet (3) , Gaston Achoundong (4) , G. Buchet (1) , Véronique Kamgang Kebeye Beyala (5) , C. de Namur (6)

1 CEREGE - Centre européen de recherche et d'enseignement des géosciences de l'environnement
2 SPEC - UMR3680 - Service de physique de l'état condensé
3 ISTO - Institut des Sciences de la Terre d'Orléans
4 Herbier National du Cameroun
5 IRGM - Institut de Recherches Géologiques et Minières
6 Biomathématiques - ORSTOM

Modern soil and litter samples from southeastern Cameroon, collected along a continuous forest-savanna transect were analysed for pollen content to define modern pollen-vegetation relationships. The pollen results, completed and compared with botanical inventories, leaf area index and basal area measurements performed in the same area, clearly registered the physiognomy, the main floristic composition and floral richness of the two sampled ecosystems. Distortions were observed between sampled vegetations and their pollen rain, related to important differences in pollen production and dispersal of plant species: this is a general feature in many tropical regions. The pollen data in the area studied reflected well the recent transgression of forest versus savanna. This permitted us to define inside the forest ecosystem more successional vegetation communities than the botanical surveys allowed.

Keywords: calibration; Cameroon; modern pollen spectra; palynology; vegetation communities

Domains: Geochemistry; Global Changes

A. Vincens, M.A. Dubois, Bernard Guillet, Gaston Achoundong, G. Buchet, et al.. Pollen-rain-vegetation relationships along a forest-savanna transect in southeastern Cameroon. Review of Palaeobotany and Palynology, 2000, 110, pp.191-208. ⟨10.1016/S0034-6667(00)00009-9⟩. ⟨hal-00115226⟩