Climatic Variability and Sustainability of Crop Yield in the Moist Tropics

Abstract

Except on the most fertile and level sites, production systems that attempt to mimic natural ecological processes are more likely to yield sustained crops of food and fiber in the humid tropics than are high technology systems introduced from ecologically very different developed countries. The climates and soils of the humid tropics are more diverse and variable than is commonly realized. The same biological processes that occur in tropical forests after natural disturbance occur in cultivated areas. This fact should be taken advantage of in design of sustainable agricultural systems. Row crops and small grains are ecologically better adapted to temperate than to tropical regions. Although the extreme view of the causal relationship between diversity and stability in ecosystems has been discredited, monocultures are more susceptible to disease and insect attack than are multi-species stands. Increasing atmospheric CO₂ is unlikely to have a great effect on tropical climate, but there could be an important fertilizing impact. Production of biomass fuel should be considered as part of a multiple cropping system. Implementation of an ecologically based multiple cropping system will require site-specific agricultural research, substantial skill on the part of farmers, and overcoming serious social, economic, and institutional barriers.