Desert Environments of Republic of Chad - Combating Desertification in Asia, Africa and the Middle East - page 168

The soudanian zone comprises those areas with an average annual rainfall of
800 mm or more. This region, which accounts for about 10 % of the total land
area, contains the nation's most fertile croplands. Settled agricultural communities
growing a wide variety of food crops are its main features. Fishing is important in
the rivers, and families raise goats, chickens, and, in some cases, oxen for plowing.
In 1983 about 72 % of all land under cultivation in Chad was in the soudanian
region.
The central zone, the sahelian region, comprises the area with average annual
rainfall of between 350 and 800 mm. The minimum rainfall needed for the hardiest
of Chad's varieties of millet, called berebere , is 350 mm. The western area of the
zone is dominated by the Chari and Logone rivers, which flow north from their
sources in southern Chad and neighboring countries. The courses of these rivers,
joining at N'Djamena to flow on to Lake Chad, create an ecological subregion.
Fishing is important for the peoples along the rivers and along the shores of
Lake Chad. Flood recession cropping is practiced along the edges of the riverbeds
and lakeshore, areas that have held the most promise for irrigation in the zone.
International donor attention focused on this potential beginning in the mid-1960s.
Particular attention has been paid to the traditional construction of polders along
the shores of Lake Chad. Land reclaimed by the use of such methods is extremely
fertile. Chad's only wheat crop is cultivated in these polders.
In the rest of the sahelian region, the hardier varieties of millet, along with
peanuts and dry beans, are grown. Crop yields are far lower than they are in the
south or near rivers and lakes. Farmers take every advantage of seasonal flooding
to grow recession crops before the waters dry away, a practice particularly popular
around Lake Fitri. The sahelian region is ideal for pasturage. Herding includes large
cattle herds for commercial sale, and goats, sheep, donkeys, and some horses are
common in all villages.
The Saharan zone encompasses roughly the northern one-third of Chad. Except
for some dates and legumes grown in the scattered oases, the area is not productive.
Annual rainfall averages less than 350 mm, and the land is sparsely populated by
nomadic tribes. Many of Chad's camel herds are found in the region, but there are
few cattle or horses.
6Agcutue
Production systems in the Saharan region are characterized by an agro-forestry
system that centers on the wadis and palms. Date palm cultivation, irrigated
subsistence farming, sedentary rearing of small ruminants and nomadic camel
rearing are all practised.