Spatial patterns and dynamics of woody vegetation in an arid savanna
Article first published online: 24 FEB 2009
1991 IAVS - the International Association of Vegetation Science
Journal of Vegetation Science
Volume 2, Issue 4, pages 565–572, August 1991
How to Cite
Skarpe, C. (1991), Spatial patterns and dynamics of woody vegetation in an arid savanna. Journal of Vegetation Science, 2: 565–572. doi: 10.2307/3236039
- Issue published online: 24 FEB 2009
- Article first published online: 24 FEB 2009
- Received 15 November 1990; Revision received 1 July 1991; Accepted 4 July 1991.
- Bush encroachment;
Abstract. The spatial distribution of woody plants was studied in an arid savanna in Botswana. The study included stands of mixed species and sizes as well as monospecific even-sized stands of different size classes of the tree Acacia erioloba and the shrub Acacia mellifera. In the case of A. mellifera both dense stands on overgrazed land and more open stands were included. The analysis used all plant-to-plant distances, and individuals were represented with a realistic canopy extension. The mixed stands showed aggregated distribution of individuals, mainly caused by strong clumping of small shrubs. In A. erioloba saplings were aggregated, small trees were randomly or regularly distributed and large trees were randomly spaced. In open stands of A. mellifera aggregation increased with size of the shrubs, while in dense stands with overgrazing aggregation decreased with increasing size. The different patterns are discussed in relation to the relative importance of inter- and intraspecific competition for water and of disturbance by fire as regulatory mechanisms for total amount and spatial distribution of woody plants in this savanna.