Dougill, A. J. and Heathwaite, A. Louise and Thomas, D. S. G. (1997) Cattle ranching and ecological change in the Kalahari, Botswana:a hydrological perspective. In: Sustainability of Water Resources under Increasing Uncertainty. IAHS Publications, pp. 469-477. ISBN 1-901502-05-8
Full text not available from this repository.Abstract
Changes in land use in semiarid savannas to intensive cattle ranching have been widely equated with changes in vegetation communities, notably bush encroachment. Increased availability of soil water in the subsoil has been assigned as both a cause and a consequence of this ecological change. Here we investigate the applicability of this association in an intensively grazed area of the Kalahari sandveld, Botswana. Studies show that no significant differences exist between profile patterns of soil water availability, or hydraulic conductivity and field capacity, between bush dominant compared to grass-dominant sites. Vegetation changes are determined predominantly by interactions of grazing levels, fire occurrence and natural rainfall variability. Pastoral management strategies should therefore account for the interactions between these variables to prevent convergence of bush dominant areas. Soil water movement in Kalahari soils remains largely restricted to the upper 2-3 m of the soil implying that groundwater recharge is negligible and that important consideration of the extent of groundwater resources is required