Fjölrit RALA - 05.12.1999, Blaðsíða 63

RALA Reportno. 200
Desertification in Botswana
Mitchael B.K. Darkoh
Department of Environmental Science, University of Botswana, Private Bag 0022, Gaborone. Botswana
Tel: (267) 3552522: Fax: (267) 356591: E-mail: dark.ohmb@noka.ub.bw
ABSTRACT
In terms of desertification, Botswana is one of the most seriously affected countries in the Kalahari
Region of Southem Affica. Problems include overstocking, large-scale vegetation depletion and
changes, especially around water points, and accelerated soil erosion by wind, sheetwash and gully-
ing. Part of the desertification problem is natural in such a semi-arid and drought-prone environment.
But the greater part is due to pressure of commercial exploitation of a fragile ecosystem. Owing to the
increasing pressure of the already crowded communal grazing areas of the east, owners of large herds
have, in the iast three decades, been moving westwards, establishing permanent cattle posts in the
Kalahari sandveld and spreading conditions of overstocking and degradation of vegetation on a large
scale. The move into the Kalahari sandveld has been facilitated by the Tribal Grazing Lands Policy
(TGLP), introduced in 1975, which encouraged owners of large herds to move them out of the
crowded settlement areas, to the sandveld where they would be' given exclusive rights to land to es-
tablish fenced commercial ranches. Impetus was also provided by the impact of modem science and
technology that provided veterinary care and new sources of water by means of deep drilling bore-
holes. Recent satellite imagery reveals that there has been considerable uncontrolled development of
cattle posts in areas set aside for wildlife management, resulting in the emergence of land use conflicts
and extensive degradation of the tree savannas.
Key words: Botswana, desertifícation, Kalahari ecosystem, rangeland degradation.
General features
Botswana straddles the Tropic of Cap-
ricom (Figure 1). It is a land-locked
country with an area of 582,000 km“,
80% of which is covered by the Kala-
hari Desert. The dominance of the latter
gives a misleading impression of Bot-
swana as a country covered by an un-
productive and expansive desert. The
Kalahari, however, is not a true desert.
It is in fact covered by a vegetation
mantle that ranges from woodland and
close-tree savannah in the north, to low
tree and shrub savannah in the south
and west. Four main ecological regions
are recognized in the country: the hard-
veld occupying most of the eastem part
of the country, the sandveld covering
most of the Kalahari desert, the alluvial
plains of the Okavango-Chobe system;
and the lacustrine plains of the Makga-
dikgadi Pans (Figure 2 and Table 1).
There is no tme desert in Botswana, but
areas covered with sand dunes do oc-
cur, especially in the west and south-