Energy Sustainability in Viticulture in a Hot Climate Region in Brazil
摘要
On a global scale, agricultural systems consume approximately one third of the energy available on the planet. Viticulture is an important agricultural activity for Brazil, mainly due to the characteristics of family production and because it is a product with high added value. Studies addressing the energy balance in grape production in Brazil have rarely been conducted. The objective of this study was to evaluate the energy balance in family-based viticulture in a hot climate region in Brazil. The mean production data of 11 table grape orchards (Vitis labrusca L.), located in the municipality of Guarapari, state of Espírito Santo/Brazil, were used. The energy coefficient (MJ) of each component involved in the production process per hectare (ha) of cultivation was quantified. The energy inputs were categorized as direct and indirect energy. The study considered ripe grapes and vine pruning residues as available energy. The direct input energy accounted for 60.62% (18,515.5 MJ), and the indirect input accounted for 39.38% (12,027.01 MJ). Renewable energy contributed 24% (7180.27 MJ) and nonrenewable energy contributed 76% (23,362.24 MJ) of the entries. The ripe grapes and pruning residues corresponded to 78% (192,771.88 MJ) and 22% (52,820.00 MJ), respectively, of the outputs. The total energy efficiency (TEE), grape energy efficiency (GEE) and grape energy conversion (GEC) were 8.04, 6.31, and 0.53 kg MJ–1, respectively. The grape specific energy (GSE) and net available energy (NAE) were 1.87 MJ kg–1 and 215,049.37 MJ, respectively. The sustainability levels were considerably increased when the pruning residues were converted into viticulture inputs.