Reactions of nitrogen in the soil due to the application of organic and mineral fertilizers

This study aimeda to evaluate the reacitons of N in the soil after application of organic and mineral fertilizers in the presence or absence of uréase inhibitors. Four trials were conducted in the laboratory. One aimed to quantify the ammonia volatilization and the treatments consisted of poultry litter (PL), organomineral fertilizer (OM) and urea, combined or not with urease inhibitor tiofosfato de N-n-butiltriamida (NBPT), and a control eithout N. Other experiments evaluated various reactions of N in the soil influenced by the application of poultry litter and urea, combined or not with NBPT, in addition to KNO₃, a fertilizer coated with polymers and a control without N. The experiments were carried out in as Oxisol that had 79% clay and 2,3% organic matter. All experimental units had 1.0 kg of soil, and the amount of N applied was 200 mg kg¯¹. To evaluate the volatilization of ammonia, fertilizers were applied to the soil surface and the gas was trapped by foam collectors impregnated with phosphoric acid and glycerin. In the experiment designed to evaluate N leaching and mineralization, treatments were incorporated into the soil evaluations were performed weekly. Ammonia volatilization was small in the soil treated with PL, regardless of NBPT, and accounted for