Grasslands of the World.pdf - Disasters and Conflicts - UNEP

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Grasslands of the world
able to develop alternative, if less optimal, subsistence strategies. The effects
became visible more than 20 years later, during the 1993/4 drought . By this
time, some of the best wet-season pastures in Simanjiro District had been lost
to large-scale commercial agriculture and more livestock were forced onto the
dry -season grazing grounds in the early grazing season, depleting the season’s
grass growth sooner. The Maasai of Simanjiro found previous drought-coping
strategies precluded by loss of access to drought reserve areas which had been
enclosed inside the Tarangire National Park or allocated to large-scale commercial
farms (Igoe and Brockington, 1999).
The examples of Mkomazi and Tarangire clearly point to costs and benefits
in conservation decisions, with conflicts likely to intensify as human needs
grow.
Control of the tsetse fly and evolution of a subhumid-grassland in
southwestern Ethiopia : Ghibe Valley
Wetter grasslands and woodlands have also evolved rapidly in the last century.
One cause of that change is the control of trypanosomiasis, the disease
transmitted to livestock and people by the tsetse fly, which allowed farmers to
use animal traction more extensively (greater numbers and more healthy oxen)
and thus to expand the amount of land they cultivated at the household level
(Jordan , 1986). Despite the logic of this progression, Ghibe Valley in Ethiopia
is one of the few places in Africa where these changes have been seen clearly
(Reid, 1999; Bourn et al., 2001)
Ghibe Valley is located about 180 km to the southwest of Addis Ababa,
where the main road to Jimma descends from the Ethiopian highland massif.
Tsetse flies were first controlled in this area in 1991, using pesticide-drenched targets
and pesticide poured on the cattle themselves. Within this landscape in 1993,
just after the control , the majority of the arable land was wooded grassland used
by wildlife and the few livestock herded by agropastoral peoples. Smallholder
farms covered about a quarter of the arable land, while large-holder farms covered
less than 1 percent (Reid et al., 1997). About 90 percent of this landscape
supports soils that are moderately to highly suitable for agriculture. Smallholder
farmers grow a diversity of crop types , including maize, sorghum, tef, noug or
niger seed (Guizotia abyssinica), false banana (Ensete ventricosum), groundnuts,
wheat, beans and hot peppers, while large-holders grow a number of crops for
market (citrus, onions, maize, spices). People use the large uncultivated tracts
of grassland and woodland for settlements, hunting, wild plant gathering, beekeeping,
livestock grazing , firewood collection, charcoal making and woodlot
cultivation .
Rapid land use and land cover change was caused by the combined effects
of drought and migration, changes in settlement and land tenure policy, and
changes in the severity of trypanosomiasis (Reid et al., 2000b; Reid, Thornton
and Kruska, 2001). Each cause affected the location and pattern of land use