As the problems of impact assessement are rather intractable, a fairly simple dual approach is proposed. First the major components of environmental impact of current agricultural production systems in Africa (i.e. impact of cropping, livestock keeping, fuelwood and timber extraction and burning) are summarised. Second, "danger zones" in which current and future environmental impacts will be most severe and on which ILCA has focused its problem solving-research is identified.

As the problems of impact assessement are rather intractable, a fairly simple dual approach is proposed. First the major components of environmental impact of current agricultural production systems in Africa (i.e. impact of cropping, livestock keeping, fuelwood and timber extraction and burning) are summarised. Second, "danger zones" in which current and future environmental impacts will be most severe and on which ILCA has focused its problem solving-research is identified.

This paper describes the environmental degradation that has occurred in Kenya since early this century, initially due to the introduction of plantation farming. Forests have been further targeted for farmland, fuel wood, building materials and hardwood species. Range land species have also become threatened due to continued infiltration of the population. The discussion considers the efforts of the Kenyan government to legislate and administrate against the further loss of natural resources and the consequent development of environmental awareness among the populace.

En vista de la inminencia de la Conferencia de las Naciones Unidas sobre el Medio Ambiente y el Desarrollo (CNUMAD), que se reunir en junio en Ro de Janeiro, este nmero de Unasylva examina varios aspectos de las actividades forestales desde el punto de vista de la sostenibilidad.

Etant donn que nous approchons de la Confrence des Nations Unies sur l'environnement et le dveloppement (CNUED) qui se tiendra en juin Rio de Janeiro (Brsil), le prsent numro d'Unasylva examine un certain nombre d'aspects des activits forestires lies la durabilit.