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The Kalahari ecosystem is characterized by natural resource conflicts and land-use pressure resulting from intensification of human activities. This paper addresses three issues of concern associated with the Kalahari ecosystem resource management: (i) the major land-use/land cover shifts in the Kalahari ecosystem since 1970 and the resulting pattern in vegetation species composition, cover and density; (ii) the possible explanations for the observed shifts; and (iii) the, possible resource conflicts likely to arise:

Data collection involved the comparison of two sets of panchromatic photographs along two transects (Hukunsti-Ngwatle arid Tshane-Tsabong) to study land-use/cover shifts that have occurred. in. the Kalahari ecosystem between 1971 and 1986. Secondly, the nature of; possible conflicts resulting from population pressure and associated patterns of land-use was investigated,by making. observations on selected environmental variables along a 300 km transect. with diverse environments comprising different-sized settlements; vegetation communities and land-uses:

Land-use/land cover shifts have occurred within the Kalahari ecosystem as evidenced by the two transects analysed in this paper. The main changes are the retreat of grass cover up to, 18 kms from settlements and the increase in thorny and non-thorny woody encroachers closer to the settlements. In the Matsheng area, land-use/land cover gradients reflect marked - differences in human pressure. For instance; while settlements (kraals/households) and fields around Tshane (smaller and dwindling settlement) have declined to 5% at the 4 km distance in 1986; these landuses account for 22.3% of land cover at 4 km around Hukuntsi (bigger and expanding village).

Five major vegetation communities were identified using key plant species during the dry season. However, these communities do not have distinct land-use activities associated with them. Cattle densities were higher in communities found far away from settlements and water points where the grass :cover was abundant. Cattle graze far from settlements to obtain quality fodder and trek to the water points around village-pans or at cattle posts.

There are no definite boundaries between vegetation communities and land-use activities, hence a lot of interaction between activities of these zones depends :on the dispersion of resources. Shifts in land-use/cover changes can be. accounted for: by anthropogenic activities (arable agriculture, livestock grazing and human settlements) enhanced by natural factors like seasonal variations and prolonged droughts of the mid-1980s. It is argued in this paper that potential remedial measures include biosphere conservation areas, resource zoning and resource modeling plans to determine land suitability. (C) 2003 Elsevier Science Ltd.