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Espagne: a study analyses the energy efficiency of Andalusian organic olive growing
ADIT, janvier 2009
http://www.oleociencia.com/
     The contribution of organic olive growing, especially on dryland, to non renewable energy saving in Andalusia is considerable. It is feasible to cut down further on the unnecessary use of machinery for soil preparation and weed control to improve energetic efficiency
     The current situation of worldwide concern over the emission of greenhouse gases and its effect on the climate demands an evaluation, from the perspective of energy efficiency and more specifically of non-renewable energy sources, of tendencies for change in the management of agricultural systems which have arisen in recent years. In this context, Gloria I. Guzmán and Antonio M. Alonso, from the Research and Training Centre for Organic Farming and Rural Development of Granada (Spain) have evaluated the contribution of organic olive growing to the increase in the energy efficiency of Mediterranean agriculture, distinguished according to type of watering regime and intensiveness of cultivation. The research work has been supported by the European Commission, the Education and Science Ministry of Spain and the Innovation, Science and Enterprise Department of Andalusia Government.
     The results show, on one side, the lower energy efficiency of irrigated land as opposed to dryland (i.e. non-irrigated) regardless of their style of management and, on the other, the greater non-renewable energy efficiency of organic olive growing in comparison with the conventional production. Nevertheless, organic management could still improve its energy efficiency if it further adjusts and internalizes the flows of nutrients needed in order to achieve greater sustainability.

Towards energetic self-sufficiency
     Based on the categories analysed here, it could be concluded that the contribution of organic olive growing, especially on dryland, to NRE saving in Andalusia is considerable. Of the 42,148 hectares in existence at the end of 2006, between 60% and 65% are traditional dryland olive groves on steep Pedroches-style slope and 20% are traditional dryland olive groves on moderate Sierra Mágina or Granada-style slope. Only 6.4% of organic olive groves in Andalusia are on irrigated land. Those which remain to make up the 100% fall into other dryland categories which have not been taken into consideration in this study, as they are not representative of the overall situation.
     Nevertheless, there is room for further improvement in the sustainability of organic olive growing through greater self sufficiency within the territory it occupies and, consequently, a lower rate of importation of energy flows originating from other ecosystems. The use of alperujo compost and temporary plant covers are strategies which do not involve extra land usage. This is a highly relevant point, since the need of organic projects to devote part of their farmland to generating the flows of nutrients and energy required to effectively reduce imports of organic material from other agro-ecosystems has on occasions been considered a drawback of organic production.