EFFECTS OF IRRIGATION INTERVAL AND WATER DEPTH ON LIMESTONE REACTIVITY IN OXISOL

Owing to high aluminum levels, soil acidity limits agricultural productivity in tropical regions. Liming is essential for increasing the soil pH and neutralizing toxic aluminum, and its effectiveness depends on water availability from rainfall or irrigation. The objective of this study was to evaluate whether different irrigation intervals and depths modify the reactions of limestone applied in an Oxisol. The study was conducted in an agricultural greenhouse at Rondonópolis-MT, with 6 treatments, in a 3 × 2 factorial scheme, with three irrigation intervals (2, 5 and 10 days) and two irrigation depths (50 mm and 100 mm). The irrigation depths were divided into five applications according to the intervals described in the treatments. The variables evaluated were the soil pH; potential acidity (H++Al3+); exchangeable Ca2+, Mg2+ and Al3+ contents; base saturation (V%); and cation exchange capacity (CEC). Analysis of variance and Tukey’s test (p