Soyabean monoculture with inadequate agricultural practices has resulted in losses of soil organic matter in the Brazilian cerrado, especially in sandy soils. This has led to erosion, reduced cation exchange capacity and water storage, and diminished fertilizer use efficiency. One of the ways of avoiding the loss of soil organic matter is to reduce tillage, as in the system of direct (as opposed to conventional) planting, and the use of this system is growing in the cerrado region. This paper reviews work that has been done on the correction of soil acidity and fertilizing with macronutrients in the direct planting system, both before and after crop establishment. The section on soil acidity discusses both surface (0-20 cm) and subsurface (20-60 cm) acidity, and the effects of correction with limestone or gypsum under conventional and no tillage systems, and on cotton and soyabean yields under a direct planting system. The section on fertilizers looks at the effects of liming, conventional and no tillage systems and dry farming on soil macronutrient content (with particular reference to nitrogen, phosphorus and potassium) and crop yield (with data for maize). Soil organic matter content is also compared under conventional and no tillage systems.
