Incluye 44 referencias bibliográficas en la página 123

The use of improved fallows has been proposed as a management alternative to shifting cultivation in the tropics. Managed fallows are quite widespread in the Americas, producing biological and economic benefits, however, cases in which both advantages are realized are scarce. In this article we evaluate the economic viability of forest fallows managed with planted timber tree species to replenish soils and provide economically valuable timber. At a 5% real interest rate, the enriched fallow-subsistence agriculture system yields land values from USD 5000-12 000 ha-1. The results suggest that managing forest fallows in this manner can make shifting agriculture sustainable and economically competitive. Although the experiences are site-specific, the species used have broad distribution in Latin America and we expect that the systems could be transferred to other areas with similar ecological and socioeconomic conditions.