Responses of Herbaceous Savanna Vegetation to Land Use and Habitat Conditions: Investigations along a Climatic Gradient in West Africa

Savanna ecosystems cover one eighth of the earth's land. They are characterised by the co-dominance of herbaceous vegetation and less-abundant woody species. In West Africa, savanna ecosystems are thought to undergo dramatic alterations in species composition in response to changes in climate and land use. However, little is known about how these factors interact to affect vegetation. Previous studies have focused primarily on woody species; studies of herbaceous species are lacking, despite the fact that these species comprise 75–90% of the biomass of the savanna.

In this study, we focus on the responses of herbaceous vegetation to the interaction of land use and climate variables in different habitats. First, we identify general herbaceous species response patterns and processes using a functional trait approach. We assume that plants with similar ecological traits respond to environmental changes in similar ways. Second, we monitor photosynthetic capacity parameters in the most dominant herbaceous savanna species as an eco-physiological assessment of competitive strength; this will be conducted in varying climatic conditions, land use regimes and habitats. Finally, using a subset of herbaceous species representing different life-history types, we investigate how local land-use intensity and climate affect plant populations to gain insights into the development of typical herbaceous savanna species.

Projektpartners: University of Jena, University of Ouagadougou/Burkina Faso