Fjölrit RALA - 05.12.1999, Blaðsíða 68

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Desertification in Botswana
by about two and a half times between 1965 and 1976 (Perkins 1991). Recent satellite
imagery reveals considerable uncontrolled expansion of cattleposts into areas set aside
for wildlife management, resulting in the emergence of land use conflicts and exten-
sive degradation of the tree savannas. Examples of land use conflicts are (Amtzen et
al. 1996):
• Conflicts between cattle and wildlife: competition for land, water and grass,
predation, disease risks.
• Conflicts between cultivation and cattle/wildlife: crop damage, experienced
by up to 80% of the cultivators.
• Conflicts between cattle/wildlife and gathering of veld products, such as
mokola palm in the north; however, most changes in gathering opportunities
are undocumented.
Conflicts tend to increase during droughts when the ecosystem is under stress,
when resources are more limited and people traditionally move in search of “reserve”
resources. Desertification in Botswana generally takes a variety of regressive forms
including (Cooke 1983, Darkoh 1989);
• The deterioration of land or reduction in grass cover and herbaceous biomass
radially outward from watering points caused by excessive grazing, concen-
trated trampling by cattle, and uncontrolled veld fíres.
• Large-scale vegetation changes resulting in some species becoming rare, and
other, usually useless or inedible species, invading the area.
• Loss of topsoil by wind and by sheet and gully erosion.
These conditions are particularly common in areas under communal land tenure
and land-use systems and can be seen all over eastem Botswana. One example of this
progressive land degradation can be seen in the Kgatleng district in the south-east,
where, between 1960 and 1981, grass basal cover has dropped from 6-15% to 0-2%
(Van Vegten 1981).
In the communal areas, the main vegetation changes consequent upon heavy (or ex-
cessive) grazing are bush-encroachment and changes in the species composition of
grasses mainly from perennial to annual species (Ringrose et al. 1996). A further
problem lies in the increase of bare soil areas which are increasingly subject to wind
or water erosion or altematively may lose viability through compaction (Ringrose and
Matheson 1987a,b). Rangeland degradation is widely blamed upon the ‘tragedy of the
commons’ (Hardin 1986), an open access problem held to be the result of the grazing
of individually-owned livestock on communally-held rangelands (Abel 1992). Under
this regimen, individuals are said to maximise benefits by putting extra animals on the
rangeland while relegating the costs in reduced grazing and range degradation to the
whole community. There is often reluctance to reduce numbers, even in times of
drought (Stanford 1983, Abel and Blaikie 1989). This is partly due to the fact that tra-
ditional herd management is prestige-oriented (animals being considered as a stock of
wealth, bringing with it social standing in society). However, many farmers aiming at
increasing their herd size, are opportunistic about grazing on either communal pasture
or on their own farms for economic reasons other than prestige (Rampha 1996).
Ranch owners fmd it convenient to let their cattle graze in the communal area, taking
them back into the ranches once grazing conditions become degraded in the commons