Fjölrit RALA - 05.12.1999, Blaðsíða 84

82
Desertification in Ethiopian highunds
Areas receiving 300-700 mm annual rainfall cover 36.7 million ha (30% of the to-
tal land area) and fall within the xeric soil moisture regime. The cultivated area in this
zone is 1.1 million ha and it is a home for about 4.5 million nomadic and semi-
nomadic pastoralists. This zone is also subjected to low and erratic rainfall, recurring
droughts, soil moisture defícit and salinity problems. Overgrazing, poor soil manage-
ment practices and deforestation are the major man induced causes of desertifícation
in this zone. Areas getting 700-1000 mm of annual rainfall cover 22 million ha (18%
of the total land area) and are classified in the ustic soil moisture regime. The land
cultivated in this zone is 9.5 million ha and it is a home for 13.7 million people. The
major problems in this zone are low soil moisture, re-curring droughts, overgrazing,
deforestation, and poor farming practices. This zone is an important cereal producing
area in Ethiopia (mainly dominated by ox-plough cereal mono-culture farming sys-
tem). The effects of droughts, erratic and low rainfall in this zone are very detrimental,
because most of Ethiopia’s grain production is concentrated in this area.
Human induced causes of land degradation
Overgrazing
Ethiopia’s livestock population is estimated to be 78 million and the poultry at 30
million by 1994 livestock census fígures. From this 78 million livestock population,
75% (48.5 million) and nearly all the poultry population is located in the highland ar-
eas above 1500 m a.s.l. Therefore, the pasture and rangelands in the highlands are
very severely overgrazed. Thus, overgrazing is much more severe in the highlands
compared to the lowland areas. Recent studies carried out in Semen Omo zone in the
southem Ethiopian Highlands, concluded that the forage bio-mass produced for live-
stock shows high stocking rates with concentration of animals of up to 23 TLU per ha
whereas under normal and well managed pastures the stocking rates is recommended
to be 2-5 TLU per ha. This means that there are far more animal units on the land than
it can support in the Semen Omo zone in Southern Ethiopia, an area which represents
one of the severely eroded land surfaces in Ethiopia (Tiku 1997).
Deforestation
The present estimates of Ethiopia’s forest base vary according to the sources of report.
FAO (1984) study reported 35 million ha while Cesen (1986) study documented 33
million ha and the State Forest Conservation and Development Department (SFCDD
1990) reported 27 million ha. This forest area includes an estimated 3.5-5.5 million ha
of high forests in various parts of the country. The estimates of annual rate of defor-
estation vary from 150,000-200,000 ha. The state planted forests up to 1989 was re-
ported to be 161,000 ha out of which Eucalyptus spp. accounts for more than 55%
(EFAP 1994). Reports show that the country’s forest resources covered 40% of the
total land area some 100 years ago but now forests cover less than 5% of the country’s
land area.
From the information available, the rate of deforestation in Ethiopia is alarming and
the rate of afforestation is very negligible in light of the very high rate of forest clear-
ing for fuel, expanding agricultural land and construction purposes. Deforestation
leaves the land surface barren and open to serious land degradation processes.