Autor: David M John

Freshwater is the resource contributing perhaps more than any other to the nutrition and welfare of the African people, and yet there are considerable gaps in our knowledge of aquatic systems on the continent compared to those in Europe and North America. This was evident when I came to write what originally was intended to be a short review chapter on the botany of the inland waters of tropical West Africa. I soon discovered there to be a surprisingly large body of information on the subject though much of this was widely scattered in research papers and obscure reports. It was thus not readily available especially to researchers in Africa who often have limited access to the literature. There were found to be no recent reviews on the botany of any of the lager aquatic systems in tropical West Africa with the exception of the region's largest lake, the hydrologically very interesting Lake Chad (see Carmouze et al., 1983 b). No comparable accounts exist for the vast man-made lakes created in the 1960s and 1970s by the damming of such major rivers as the Volta and Niger. In general reviews of African limnology some mention is often made of aquatic botany in West Africa. Unfortunately the emphasis in these works is invariably on East Africa reflecting often the writer's own field experience and the great wealth of published research usually dealing with some of the fascinating lakes of the Rift Valley. It is hoped that the present work goes some way towards redressing this balance by bringing together in a single volume much of what is known of the aquatic plants of tropical West Africa. The early chapters are intended to provide an introduction to the physical, chemical and botanical features of the inland aquatic and semi-aquatic habitats of West Africa. Some of the more general features of the macrophytic vegetation and of the algae are considered in the later chapters. To do justice to the aquatic macrophytes the services of an ecologist with first hand experience of them in the region was needed as my own special interests are in the algae. It is hoped by so doing that this publication will serve as a stimulus for further research on African aquatic systems, especially by African Universities and other indigenous research institutions in order that a body of expertise will develop within the continent.