Developing a decision support tool for evaluating the environmental performance of olive production in terms of energy use and greenhouse gas emissions

Abstract

Analysis of energy consumed and greenhouse gases (GHG) emitted by farming systems is considered an important part of an environmental performance's evaluation, especially within an agroecological context. In this study, we focused on the aspects of energy use and GHG emissions of olive production, a representative Mediterranean cropping system with a global perspective. Management practices, inputs and yield were monitored in olive orchards under different management systems (organic, integrated and conventional). The aim was to support the development of a specialized software-based tool for assessing and improving the environmental performance of olive production, with regards to input management, energy use and GHG emissions. Analysis of energy use focused on farming inputs, machinery use and human labour. Both the sum energy (SE) and its non-renewable part (NRE) were considered and the SE intensity and SE and NRE efficiency were calculated. The GHG emissions were estimated in terms CO2-equivalents, following the IPCC methodology and the emissions intensity was calculated. Main practices related to high energy inputs, were found to be the use of fossil fuels, consumed by machinery for soil management, harvesting and pruning, followed by use of synthetic fertilizers and labour. Carbon emissions presented a similar trend, with the use of synthetic fertilizers and of fossil fuels as main GHG sources. Energy use, regarding specific practices and inputs, as well as its SE intensity and efficiency and NRE efficiency, were not statistically different between management systems, except for pesticide use. Nevertheless, organic orchards presented a tendency for lower energy use. GHG emissions and emissions intensity increased significantly with management intensity, being higher under conventional management, mostly due to burning of pruning residues. Based on the above, a crop-specific Decision Support Tool (DST), named "CO2MPUTOLIV 1.0″ was developed and validate for calculating energy use and GHG emissions in olive orchards and providing guidelines for a sustainable olive production. The software tool is freely accessible online (www.computoliv.eu), targeting stakeholders, like farmers and agronomists. It is expected to contribute to the assessment of environmental performance of olive farming and the transition towards a sustainable olive farming system.