Rangeland condition and feed resources in Metema District, North ...

The pastoral rangelands of Ethiopia are located around the peripheral or the outer edge
of the country, almost surrounding the central highland mass (Alemayehu 2004). The
areas are classified as marginal arable and non-arable land and comprise about 62%
(767,600 km 2) of the country’s land area. Most of these areas are below 1500 metres
above sea level (masl) with the southwest and the southeastern areas having an altitude
of around 1000 masl and the southeastern and southwestern rangelands rising up to
1700 masl (Kidane 1993). Climate in the lowlands includes arid (64%), semi-arid (21%)
and subhumid (15%) zones largely defined by four rainfalls and temperature regimes.
These zones vary markedly in terms of number of plant growing days per year, forage
production, common plant associations, livestock and human carrying capacities and
incidence of important livestock diseases. Ethiopia has over 70 million heads of livestock,
and the lowlands are home to 12% of the human and 26% of the livestock population
(CSA 2009). Various forms of pastoralism and agropastoralism dominate. Livestock
depend upon rangelands consisting of native vegetation, with crop residues increasing in
importance as livestock feed as annual rainfall increases. According to Coppock (1994),
calculated for the lowlands overall, roughly six people/km² are dependent on 11 Tropical
Livestock Units (TLUs), which are composed of cattle (49%), goats (16%), equines (16%),
camels (12%) and sheep (7%). In contrast, the highlands support 72 people/km² and
dependent on 44 TLUs/km² which are dominated by cattle (76%), equines (14%), sheep
(8%) and goats (2%). Thus, although the lowlands comprise over 50% more land area
than the highlands, the lowlands have only 40% as many TLUs at one-quarter the density.
2.3 Major livestock feed resources in Ethiopia
The major livestock feed resources in Ethiopia are natural grazing and browse, crop
residues, improved pasture, and agro-industrial by-products (Alemayehu 2004). The
feeding systems include communal or private natural grazing and browsing, provision
of crop residues and cut-and-carry feeding. At present, stock are fed almost entirely on
natural pasture and crop residues. Livestock are grazed on permanent pastures, fallow
land and cropland aftermath (Alemayehu 2004; Abule et al. 2007a).
2.3.1 Feed availability and nutritive value of range forage
Feed availability
Natural pasture comprises the largest feed resource and estimates of its contribution to
overall feed resource vary greatly. This is because the quantity and quality of native pasture
varies with altitude, rainfall, soil and cropping intensity. Seasonal fluctuations of feed
resources in the tropics also follow the pattern of vegetation growth which is modified by
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