DESLOCAMENTO VERTICAL DE NITROGÊNIO EM UM NEOSSOLO REGOLÍTICO ADUBADO COM ESTERCO BOVINO

Abstract

Nitrogen is an essential element for plant growth, however its high mobility makes it one of the most limiting factors to crop development. The nitrogen mobility in soil is mainly due to its negative charge, when in the NO3 form, because it is not adsorbed to soil colloids, which mostly have also negative charges. Furthermore, the reactions from the bacterial activity that convert the NH4+ to NO2- and further in NO3-, thus contribute to decrease N in soil on the deeper layers, by leaching. Seeking compensation for such N losses, some agriculturist recur to adding organic matter in the soil, where most often the source used is the animal manure of the same property. In some cases, the manure that is not enough to cover the losses, and in others there is a surplus on the farm, and are applied in large amounts, in this latter case, the concern is even greater when the soil is sandy, as N losses intensify. The goal of this study is to evaluate the vertical displacement of NO3- and NH4+ in samples Entisol eutrophic using rainfall simulator in family farming area fertilized with cattle manure.