PHYSICAL AND CHEMICAL CHARACTERISTICS OF SOME SOILS OF MINAS-GERAIS AND METHODS FOR DETERMINING LIME REQUIREMENTS

This work shows the correlations between the lime requirements calculated with four differents methods for several Minas Gerais soils. Lime requirement was calculated according to Exchange Aluminium and calcium and magnesium and bases saturation methods and lime requirement to pH 6.0 calculated through an incubation curve. Considering pH 6.0 as ideal, soils were separated from their standards deviation, into variations classes of 0 to 5%, 5 to 10% and more than 10% to reach ph 6.0. The lime requirement calculated on bases saturation method showed the best correlation with soil phisical-chemistry characteristics as clay content, cation exchange capacity at pH 7.0 and organic matter. All methods showed a requirement that, applied, caused variability around pH 6.0. The bases saturation was the method with lower variability. The correlation between pH and bases saturation showed 40% as the media saturation up to pH 6.0 under controlled conditions.