Doses of Acidity Corrective in Some Chemical Attributes to Build the Fertility of Concretional Soils

Abstract

With the increase in agriculture in the state of Tocantins, especially with soybean cultivation, areas with concrete have been increasingly applied to high doses of limestone, although they do not know the dynamics of the reaction of these correctives in the soil conditions of Tocantins. For the study, soil with different soil/gravel ratio and 01:02, 01:05 and 1:10 proportions of fine ground/gravel were used. The incubation assay was installed under a greenhouse in a completely randomized experimental project. The 15 treatments were obtained in a 3x5 factorial scheme, combining three fine ground/gravel (01:02, 01:05 and 01:10) and five limestones (0; 1.0; 2.0; 4, 0 and 6.0 t ha−1). The soils were prepared as TFSA and sent to the soil laboratory for analysis of Ca + Mg, Ca, Al, potential acidity (H + Al) and pH. Al levels and potential acidity (H + Al) were reduced and Ca and Ca + Mg contents were significantly increased with the increase of the limestone dose in gravel ratios. The pH of the 1:5 ratio decreased until reaching its lowest value at the dose of 3.31 t ha−1, increasing the dose rate greater than 3.31 t ha−1. The pHs of ratio 1:2 and 1:10 increased as the limestone dose increased. Ca, Ca + Mg levels and pH value are already at adequate levels in 0t ha-1dose of limestone, and it is not necessary to recommend correctives for gravel relations.