Fontes de cálcio e magnésio e movimento de cátions em colunas de solo

Abstract

The soil acidity is one of the most limiting factors in farm production. The objectives of this work are to evaluate Calcium and others cations movement after addition of Calcitic calcareous, Dolomitic calcareous, Gypsium, Oxide calcium, and a mix of Calcareous and Gypsium and evaluate the capacity of these materials to release Ca, Mg and correct soil pH in depth. It was used samples from a Neossolo Quartzarênico sampled under natural vegetation with low quantities of Ca and Mg exchangeable. It was used PVC columns, with 12 cm of diameter and 60 cm of height, filled with sequenced samples of 10 cm from the profile. The correctives in enough quantity to reach 80% of basis saturation of 10 cm superficial were mixed with the soil on the superficial (5 cm) columns. In the columns were applied 12 water blades of 48 mm (8 blades with gaps of 5 days; 1 blade with gap of 10 days and 3 blades with gaps of 20 days). All percolated were collected, measured and determined the EC, pH, Ca, Mg, K and titulated acidity. The experiment was conducted from a period of 120 days with 36 columns, in the first 60 days half columns were tokk off. Soil samples were took from the columns and eva luated pH, Ca, Mg, Al, K and potential acidity. The Gypsium and the mixed of Calcarium and Gypsium led to a greater loss of cations, whereas Calcitic calcarium, Dolomitic calcarium and Oxide calcium did not led to significant losses. Gypsium increased the quantities of Ca in all profile, but little changed soil pH. Calcitic calcarium was the most effective to increase soil pH in 0-5 and 5-10 cm.