9 - Regional Hydrology and Water Resources in the African Humid Tropics

Summary

ABSTRACT

This paper reviews the current hydrological and water resources knowledge in Africa and some of the associated problems of the humid tropical region of Africa

Data availability and accuracy are identified as major constraints. Estimates of water resources vary widely. Knowledge about the lakes in the region is inadequate, apart from information on their physical characteristics. A generalized knowledge about the sediment yield for the African region has been put forward recently but is only tentative because of the data constraint. Subregional and regional syntheses are needed on water quality, droughts and low flows. Such a synthesis is available for groundwater, but needs updating with the large amount of data that has been made possible through the International Drinking Water Supply and Sanitation Decade. The impact of land degradation and climate variation on the hydrology and water resources of the region is an area of study that also needs urgent attention.

PHYSIOGRAPHY

Location

The location of the humid tropic region is the low-lying areas within the two tropics of Cancer and Capricorn – basically as defined by Chang and Lau (this volume). Figure 1 shows the African regional coverage which generally lies between latitudes 15°N and 20°S. The region is bounded on the west by the Atlantic Ocean, on the east by the Indian Ocean, on the north by the Sudano-Sahelian belt and Sahara Desert and on the south by the Kalahari Desert.