Alternative management for olive orchards grown in semi-arid environments: an energy, economic and environmental analysis

The objective of this study was to test a more productive and sustainable system compared to the traditional approach to managing olive orchards in semi-arid environments. The main features include a) using treated urban wastewater for drip irrigation; b) incorporating soil management techniques for preserving soil quality; c) exploiting environmentally friendly techniques in order to increase the atmospheric carbon storage in the soil. The comparison between the two management systems, 'alternative - AS' and 'traditional - TS', was carried out through an energy, economic and environmental analysis. The data used in this paper refer to averages for the period 2000-2008. Energy values were calculated by multiplying the amount of farm inputs by the related energy conversion factors. The total input energy per kg of olives was 4.97 and 3.04 MJ in the alternative and traditional systems, respectively. The economic analysis, performed according to the Standard Result Indicators of the European Farm Accounting Data Network (FADN), showed that the Farm Net Income of the AS was considerably higher (5948 € ha-1) than the TS (1518 € ha-1).The environmental analysis was carried out according to a Life Cycle Assessment (LCA) methodology using SimaPro7.2. In the AS, emissions were 0.29 kg CO2eq per kg of olives, while in the traditional olive orchard emissions were equal to 0.42 kg CO2eq kg-1. Under our experimental conditions, the alternative system seemed to be a much more effective management model in terms of productivity, environmental saving and profitability. Although the AS was the most energy-consuming system, its greater productivity enabled a more "sustainable" kg of olives to be produced, at least regarding CO2eq emission. Our combined use of various methodologies (LCA, energy and economic analysis) could provide critical information for policy makers and producers and help them in making strategic choices.