The humid tropics are exposed to an unprecedented modernisation of agriculture involving rapid and mixed land-use changes with contrasted environmental impacts. Afforestation is often mentioned as an unambiguous solution for restoring ecosystem services and enhancing biodiversity. One consequence of afforestation is the alteration of streamflow variability which controls habitats, water resources, and flood risks. We demonstrate that afforestation by tree planting or by natural forest regeneration can induce opposite hydrological changes.

Se esquematizaron metodos alternativos para llevar a cabo la cosecha y el beneficio de la semilla de Andropogon gayanus. La cosecha puede ser totalmente manual, total o parcialmente mecanica. La cosecha manual ofrece los mas altos rendimientos de semilla pura con un contenido aceptable de material inerte, y obtenida sin recurrir a ningun acondicionamiento mecanico. Este metodo de cosecha esta restringido, sin embargo, a regiones donde haya mano de obra abundante y disponible.

La produccion comercial de semillas de Andropogon gayanus es potencialmente factible, pero es necesario desarrollar tecnologia apropiada para la cosecha y el beneficio. Problemas inherentes al cultivo, como su altura en la madurez y el desuniforme y amplio rango de distribucion de las semillas, han dificultado la implementacion de los metodos mecanicos tradicionales de recoleccion. Ademas, las caracteristicas morfologicas de las espiculas y la presencia de aristas, espiculas esteriles y abundante pelusa ocasionan problemas particulares en el beneficio de las semillas de esta especie.

This article presents criteria and recommendations to support the landuse planning process in the savanna land ecosystem of the municipality of Puerto Lopez. These criteria were established from the analysis and correlation of the characteristics of the landscape and soils, taking in consideration biophysical and management aspects. They are expressed as limitations and potentialities for the crops, agroforestal production and conservation, and are given for the different geomorphological positions.

This paper examines the conversion of Indonesia’s natural forests to timber and tree crop plantations, notably oil palm. The principal aims are to understand the impact of this process on natural forest and on forest-dwelling people, and to establish whether past and present policies governing this process are meeting their objectives.

The potential of Crotalaria ochroleuca check for this species in other resources as a green manure crop was evaluated in a series of on-station and on-farm trials on reddish kaolinitic loam and sandy clay loam soils in Uganda. Production of the green manure by intercropping Crotalaria with either maize or beans was found to be feasible with little reduction in food crop yield and a mean Land Equivalent Ratio of 1.3. The large amounts of N in the Crotalaria indicates that large quantities of N were biologically fixed.