Dry forests in SW Burkina Faso
Small patches of dry forests are found like islands in some areas of the savannas of South Western Burkina Faso. The objective was to find out which factors enable the persistence of dry forests in an environment under extensive human impact – by shifting cultivation, pastoralism and bush fires. At eleven dry forest sites we conducted plant sociological relévés and recorded the soil profiles.
Two different plant communities can be distinguished: 1. the Mimusops kummel-Malacantha alnifolia group on moister soils near water courses, 2. the Fagara zanthoxyloides-Pterocarpus erinaceus group on dry, well-drained soils. The soils are often shallow, stony and not very attractive for agriculture, thus favouring forest preservation. A dense shrub layer and the absence of grasses prevent these forests from annual bushfires and lead to the accumulation of organic material in the upper soil horizons.
Separate relévés of the tree, shrub and herb layer illustrate the regeneration of tree species and allow for conclusions on the individual history of each forest. Some of them are clearly secondary while others might be relics of formerly primary dry forests. However, none of them can be called “virgin” forest as there is ubiquitous evidence for human impact. The forest patches are clearly an integral part of the cultural savanna landscape in South West Burkina Faso.
Publications
Müller-Haude, P. & Neumann, K. (1995): Böden und Vegetation in Trockenwäldern Südwest-Burkina Fasos. - Berichte des Sonderforschungsbereichs 268, 5: 177-188. Frankfurt am Main. pdf
Neumann, K. & Müller-Haude, P. (1999): Forêts sèches au sud-ouest du Burkina Faso: végétations - sols - action de l’homme. - Phytocoenologia 29(1): 53-85.
