Se presenta un manual detallado que describe los metodos estandarizados de procedimiento para el analisis de suelo y tejidos vegetales con el objeto de 1) proveer a los investigadores de America tropical informacion sobre metodologia existente para los analisis de suelos acidos y plantas del tropico, 2) incrementar entre las instituciones nacionales e internacionales un intercambio de informacion sobre las metodologias empleadas en America tropical para definir y aplicar las mejores y 3) hacer que los analisis de suelos y de plantas constituyan una parte dinamica de la investigacion y permi

Summarises the literature on the alleged defects of traditional systems of land tenure in Nigeria. Reviews the provisions of the land use decree and their implications for rural land tenure.

Assesses the effect (balance or imbalance) of the present relationships between the natural resource base and human activities; examines the role of some potentially destabilising forces, i.e, international markets, government programmes and socio-economic stratification; and reviews government's role in terms of its contributions to prudent natural resource management and options for the promotion of sustainable rural development.

Niger is a landlocked country in West Africa located between 11°37´ and 23°23´ north latitude and between 00°10´ and 16°00´ east longitude, with an area of 1,267,000 square kilometers. Niger shares borders with Algeria and Libya in the north, Chad in the east, Nigeria and Benin in the south, and Burkina Faso and Mali in the west. Three-fourths of Niger is cov¬ered by the Sahara Desert. The southern part of the country is in the Sahelian climate zone, with Sudan savannah vegetation.

Canavalia brasiliensis (canavalia), a drought tolerant legume, was introduced into the smallholder traditional crop-livestock production system of the Nicaraguan hillsides as green manure to improve soil fertility or as forage during the dry season for improving milk production.