DINÂMICA DO NITROGÊNIO MINERAL NO SOLO E PRODUÇÃO VEGETAL EM FUNÇÃO DA ADUBAÇÃO NITROGENADA DA PASTAGEM E DO MILHO EM SISTEMA DE INTEGRAÇÃO LAVOURA-PECUÁRIA

Abstract

The integrated livestock crop system is beginning to be adopted by the farmers more often, because its economical efficiency, but to reach success at the activity the use of fertilizers is needful, mainly the nitrogen, which element has a high relation with vegetal growth. The objective of this study was to evaluate the nitrogen dynamics and at an integrated livestock - crop system. To reach this, an experiment was run at an integrated livestock - crop system, during at the harvest year of 2013 - 2014 in Guarapuava- Brasil. In winter, four nitrogen fertilization levels (0, 75, 150, 225 Kg N/ha) were arranged at a random blocks design, with split-plots and three replications, and in the summer two nitrogen fertilization level were used (0, 200 Kg N/ha). The amount of soil nitrate was evaluated with plants indicators. The amount of soil nitrate was strongly affected by the nitrogen fertilization levels and was also observed that its permanency at the whole system increased the mass of forage produced in the winter, and in the summer was sufficient to meet the corn extractions. In the corn crop, the plot with 0 kg N/ha in the winter and 200 kg N/ha in the summer produced the same amount of grains that produced the plot with 150 kg N/ha in the winter and 0 kg N/ha in the summer.