Environmental and Social Impact Assessment - Gibe III

Gibe III – Environmental and Social Impact Assessment 300 ENV R CS 002 C - A9003099
products only provide food for 3-6 months of the year and most of that is from post-flood recession cropping,
rather than dryland crops. Blood, milk, butter, fish and food aid cereals make up the rest of the diet for the
majority.
Crop production is an important source of forage, in the form of crop by-products such as maize and
sorghum stalks, as well as grazing on field residues. Pastoralists move animals to the plains during the dry
months, except for milking cows and calves, to take advantage of the grazing made possible by the annual
flooding of the river. They move back when the rains start and the risk of tsetse-fly borne trypanosomiasis
increases in the riverine forests.
Some NGOs are providing improved seed, of short duration crops - maize particularly, and trying to
encourage some crop diversification, e.g. with pigeon peas. NGOs active in South Omo, include Farm
Africa, PACT, EPARDA and the Catholic Church. Activities tend to be mainly aimed at supporting the
livestock sector and include; animal health services, range management, establishing livestock markets,
provision of a few sheep and goats to the poorest households who have no livestock, and establishing
“resource areas” to extend grazing by creating watering places and mineral licks.
Some of the factors limiting rainfed crop production are summarised as follows:
Low and unreliable rainfall: Low rainfall results in a short growing season which limits the choice of crop
varieties, to those which have a lower yield potential. It also restricts the farmer to growing one crop per
year. Where rainfall is low it is also likely to be unreliable and unevenly distributed during the growing
season, resulting in regular crop failures.
Shortage of good soils: Higher altitude areas where rainfed cropping is practiced are mostly hilly and eroded
and the amount of good arable land is limited.
Shortage of labour: Labour shortage limits the area that can be cultivated and livestock herding takes many
of the men and boys away during the cropping season. Compared to flood recession cropping, rainfed
agriculture requires a lot more labour for land preparation, especially where oxen are seldom used.
Low yield potential: Traditional varieties may have the advantage of being tried and tested but usually have a
low yield potential. Improved short duration varieties could increase yields under the same conditions.
Limited crop types: Reliance on relatively few crop types, especially maize which is not very tolerant of
drought, is a poor insurance against losses from drought or disease etc. and there is a need to promote crop
diversification.
Crop losses to pests: Bird damage to the sorghum crop and high post-harvest losses due to insect pests in
storage, also reduce crop production.
5.4.5.2 Flood recession agriculture
The Omo River rises during the rainy season and overflows its banks to flood the land on the plains
bordering the river, permitting crops to be grown on the residual soil moisture after the floods recede. Further
upstream where the valley slopes are too steep to allow large scale flooding, areas of recession crops are
grown on the riverbanks, especially where silt has been deposited at bends in the river.
No less than nine ethnic groups practice at least some flood retreat cultivation (See Figure 5.16) and flood
recession cropping is important in all four Weredas; Hamer, Salamago, Nyangatom, and Dasenech, from the
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