Emissões de metano e óxido nitroso em sistema de integração lavoura-pecuária em Sinop - MT

Abstract

The objective was to evaluate methane flows (CH4) and nitrous oxide (N2O) and compare them in integrated crop-livestock systems (CLI) and livestock-crop integration (LCI). The study in Embrapa Agrossilvipastoril in Sinop-MT, was made up of ILP system with crop cultivation in the first two years (soybeans in summer + maize second crop intercropped with pasture) and pasture crop in two years with Brachiaria brizantha (cultivar Marandu), and the IPL system, with two initial years with pasture and two years of crop cultivation, as described in the previous treatment. exclusive systems such as eucalyptus forest, crop (soybean + maize intercropped with pasture), and pasture with Brachiaria brizantha were used for comparisons of flows found in the CLI and LCI systems. The samples collected from November 2013 to October 2014, weekly in the morning using static cameras and syringe system. Subsequently analyzed by means of gas chromatography. The average annual flow of N2O in the eucalyptus forest and livestock were lower, while the CLI, agriculture and LCI had higher average annual consequently representing higher emissions. All systems showed oscillations of CH4, not being clearly explained by the same variables presented for N2O, but in all there were accumulations of gas. When evaluated annual average flows of CH4 eucalyptus forest showed the lowest value (-15.47 µg C m-2 h-1 ) while other systems tested negative values, but more close to zero, reinforcing the idea that CLI and LCI consume less CH4.