Análise energética da produção de milho para silagem e grãos cultivado em diferentes espaçamentos

Abstract

Considering the increasing demand for food and an agriculture ever more developed, it is important to evaluate the impacts caused by agro-ecosystems concerning sustainability. In this context, the energetic balance constitutes an important tool for this evaluation, since it allows us to account for the inputs and outputs referent to the productive system in the form of energy and to determine the efficiency of each one. The present work was conducted with the objective of evaluating the energy flows of the production process of maize for silage and grain, cultivated in three spacings, 0.90 m, 0.75 m and 0.60 m. The analysis was performed by means of accompanying the culture, for a period of 204 days (from 11/12/2013 to 06/06/2014), with each component involved (direct and indirectly) being quantified and multiplied by their respective energetic coefficients. In all spacings, there was the predominance of direct energy over the indirect energy. For the production of silage, the efficiencies for the spacings of 0.90 m, 0.75 m and 0.60 m were, respectively, 9.50%, 9.30% and 3.69%. For the production of grain, the efficiencies for the spacings of 0.90 m, 0.75 m and 0.60 m were, respectively, 11.11%, 10.21% and 10.86%.