Land degradation in the tropics is strongly associated with human population growth. The latter phenomenon is quite marked in humid areas and in the temperate highlands (Jahnke 1982). Notably in the plateaux of Sub-Saharan Africa and Asia, several pastoral systems have gradually evolved into mixed farming, in order to cope with such pressure (Ruthenberg, 1980). Land is more intensively utilized as population density increases since mixed systems are more efficient than specialized crop or livestock systems (McIntire et al.,1992). In fact, livestock crop integration allows:

La Division mixte CEA/fao de lfagriculture a été invitée à collaborer

avec la Division de l'industrie été de l'habitat à l'élaboration d'une étude révisé l'industrialisation et la cooperation economique dans la sousre gifcn de l'Afrique du nord, en établissant la partie de l'étude relative au secteur agricole (1963-1980)

Research in the various agricultural experiment stations in Ethiopia has convincingly shown that the wheat variety is in many respects inferior to imported varieties (lower yield, weaker stems, more susceptible to rust, short stalks, small heads etc.) and required to be replaced for upgraded.

Le tabac est cultivé en Afrique depuis plus de trois siècles. Des navires venus d'Amérique au début du XVII ème siècle apportèrent des semences qui furent plantées le long des fleuves dans la région occidentale ou opéraient les marchands d'esclaves. La culture s'étendit au sud du continent et en 1892, les petites plantations individuelles qui avaient gagné l'intérieur de l'Afrique du sud produisaient quelque 3 millions de kilos.

Agriculture occupies a predominant place in the economies of the African countries. The survey- of Economic Conditions in Africa 1/ reveals that in 1966 -agriculture supported- three-quarters of the- population- contributed 36 per cent of the Gross Domestic Product and accounted for at least 60 per cent of the total export earnings received by the developing African countries.

The ECA/FAO Joint Agriculture Division has been requested to collaborate with the Industry and Housing Division in the preparation of a study on "industrialization and Economic Co-operation for the North African sub-region” by providing the relevant part of the study concerning "The Agricultural Sector, 1963-1980".

Revista internacional de silvicultura e industrias forestales

An international review of forestry and forest products

Revue internationale des forts et des industries forestires

Revista internacional de silvicultura e industrias forestales

An international review of forestry and forest products