Recomendação da necessidade calagempor meio de curva de neutralização da acidez de solo do cerrado Piauiense

Abstract

Abstract: The use of agricultural amendments is an important technology to increase the volume of soil explored by roots and to provide an increase in soil pH. The methods for calculating liming use potential acidity. However, buffer methods, such as SMP or Santa Maria, are used to estimate H+Al values, or even to recommend the amount of amendment to be applied based on neutralization curves. The objective of the experiment was to define a method for recommending the need for liming appropriate for the state of Piauí through the relationship between pH and other soil acidity characteristics (buffer pH) and to validate this relationship using the acidit neutralization curve and methods for estimating the need for liming. The experiment was carried out at the State University of Piauí, Teresina, PI, at the Center for Agricultural Sciences, collecting soil (Yellow Latosol) from Cerrado in Bom Jesus, PI. The treatments consisted of the application and incubation of soil samples wit different doses of CaCO3 equivalent to: 0, 1, 2, 4, 8, 12 t ha-1. The pH values of 7.0 in CaCl2 and H2O were reached with doses of 7.8 and 5.2 t/ha of calcium carbonate, under controlled conditions. Thus, it was possible to generate recommendations for the application of correctives for Yellow Latosol in the Cerrado of Piauí based on the buffer pH reading (SMP or Santa Maria) to reach pH 6.5 in H2O and/or CaCl2.