Lixiviação de nitrato e amônio em Latossolo Vermelho distroférrico

Abstract

Nitrogen an important nutrient required by plants can undergo the leaching process and thereby contaminate the water table and water courses. Thus, the objective of this work was to evaluate the dynamics of NO3 - and NH4 + leaching in columns of deformed soil submitted to organic and mineral fertilization. The experiment was conducted in a greenhouse, 0-15 cm deep samples were collected from an Anionic Acrudox. The experimental design was completely randomized, with seven treatments: EA: birds manure; EB: bovine manure; CO: organic compound; HU: earthworm humus; GE: residue from the manufacture of gelatine; AS: Urea; TC: control without nitrogen fertilization and three replicates. During the experiment, the NO3 - and NH4 + contents were regularly determined in the leachate collected and in the soil of the columns. The highest dry matter yield of the corn plant was in the AS and EA treatments. In all treatments and in the control, NO3 - contents were higher in relation to NH4 + in the soil at the end of the experiment. The leaching of both ammonium and nitrate occurred in the following decreasing order: EA > HU > GE ≥ AS > EB > TC > CO. Considering both the plant production and the ammonium and nitrate leaching, within the limits of this study, an obvious advantage of the organic fertilizers tested in relation to conventional mineral fertilization was not observed.