ABSTRACT
The Republic of Chad is landlocked at the crossroads of Central Africa. Chad is bordered on the north by Libya, on the south by the Central African Republic, on the east by Sudan, and on the west and south by Niger, Nigeria, and Cameroon. Immediately north of the Sudanese Zone is the Sahelian Zone, which covers the middle portion of Chad. The northernmost zone, the Saharan, has a desert climate with less than 200 mm of annual rainfall. Chad's vegetational regions are almost evenly divided between the two tropical regions and the desert region. In the desert areas, there is hardly any vegetation except in the oases, where grains and dates are grown and market garden production is practiced. The recurrent drought has caused massive southward migration of herders, acceleration of deforestation, reinforcement of desertification, and disruption of harvests. In Chad's rain-fed agricultural production system, droughts and desert encroachment have caused crop failure.
