ABSTRACT
Earthworms are the most abundant invertebrate macrofauna in many tropical soils. The relative distribution of these soils vary among ecologies. Vertisols are severely constrained by their physical properties and soil moisture regime. Hydromorphic soils are constrained by water management problems, and can be highly acidic. Appropriate soil management technologies for economic and sustained agricultural production are different for different soils and ecologies. Objectives of soil surface management are to control soil erosion, favorably regulate soil temperature and moisture regimes, and stimulate biotic activity of useful soil fauna. Alfisols or Luvisols are predominant soils of the subhumid and semiarid tropics. The basis of improved technologies to supplement soil fertility include the integration of livestock and woody perennials with food crop production, and the liberal use of mulch materials and organic wastes. Removal of forest/existing vegetation cover should be done in such a way that the delicate balance between soil-vegetation-climate is not disturbed.
