Análise energética da cultura do milho para silagem irrigada por pivô central

Abstract

The lately innovation inside agriculture has intensified the use of energy sources, mainly non-renewable. As a consequence, the energy consumption of agricultural systems has significantly increased. Recent research pursuing sustainable solutions reveals that several approaches make use of the energy analysis as a tool to quantify the power demand of a given culture. Within this context, the objective of this study was to analyze the energy balance of maize silage grown at the Federal University of Lavras (CDTT-UFLA). The crop was irrigated by a center-pivot and the impact of the irrigation system on the energy balance was evaluated, considering the 1st and 2nd harvest of the agricultural calendar 2014/2015. All the maize cultivation steps were monitored, whereas energy inputs were counted through the definition of the respective energy coefficients. Considering the irrigation system, two energy sources were taken: the electric energy and the indirect energy from the irrigation equipment. The results of energy analysis showed that the crop had a total energy input of 45.643,85 MJ ha−1 and 47.303,60 MJ ha−1, considering the 1st and 2nd harvest. A significant prevail of the direct sort of energy (about 92% of the matrix) was also observed. The irrigation method represented 14.76% and 21.37 % of the maize energy matrix; nevertheless, it allowed the system to achieve high levels of productivity, resulting in an energy efficiency of 25.1 and 28.1 for the 1st and 2nd harvest, respectively.