ABSTRACT
The republic of Kenya lies on the eastern side of the African continent, between Lat. 4o40'N and 4o40'S and between Long.33°50'W and 41°45'E (NEAP, 1994). The equator bisects the country in almost two equal parts. The climate of Kenya is controlled by movement of the intertropical convergence zone (ITCZ), whose influence is then modified by the altitudinal differences that give rise to Kenya’s varied climatic regimes (NEAP, 1994). The country’s equatorial location and its position adjacent to the Indian Ocean also influence the local climate. Kenyan soils are grouped into various units (NEAP, 1994) based largely on their physical and chemical properties. These play a major role in explaining vegetation types and their distribution patterns. Kenya may be divided into four major agroecological zones (AEZ) namely the highlands, savannah, coastal, and arid and semi-arid lands (ASAL) (Figure 4.1). The zones have distinct humidity ranges, mean annual temperatures, rainfall patterns, and altitudes that largely dictate their respective ecological potentials. Kenya’s population was estimated at 27.5 million in 1995 and was growing at a rate of 2.9 percent per annum (NDP, 1997). Its economy is predominantly agriculture and agroforestry-based, contributing 26 percent to the gross domestic product (GDP) in 1997 (NDP, 1997). Agricultural activities are concentrated in the highlands (high potential), savannah, and coastal (medium potential) AEZs (NEAP, 1994).
