Sostenibilidad ambiental de explotaciones ganaderas ecológicas y convencionales en agro-ecosistemas mediterráneos de alto valor ecológico: un estudio comparado basado en indicadores agroambientales. Environmental sustainability of organic and conventional livestock farms in a Mediterranean ecosystem of high ecological value: a comparative study based on agri-environmental indicators

This paper analyzes the beef cattle sector located in the dehesa agro-ecosystem (SW Spain). The objective is to detect the more sustainable systems based on the environmental dimension of sustainability comparing three production models. RESULTS: organic farms contribute to environmental stability to a greater extent than conventional ones due to the implementation of certain farming practices. Organic farms (mainly the 'Organic 2' group of farms) do not use pesticides nor chemical fertilizers and present greater integration of livestock species, crops and trees, which has positive environmental and economic effects. This integration allows better use of food resources and conservation of the heterogeneity of landscapes, conserving natural resources and promoting ecosystem services. Coupled with this, the reduced preventive use of parasiticides and antibiotics increases the resilience of livestock and reduce environmental pollution and antibiotic resistance. In this sense, organic farms (both 'Organic1' and 'Organic 2') showed the highest scores for sustainability. No significant differences were observed in manure management. This aspect was due to the extensification of dehesa farms, which prevents the accumulation of manure in a given area. Then grazing lead to improving soil quality and reduces nutrient leaching. Regarding soil and crops management, any group of farms showed to carry out more environmentally agricultural practices (i.e. conservative agriculture, etc.). This could be due to poor training and awareness of managers with regard to this technical area, as well as an importance lack of association between crops and livestock. It has been observed that Organic 2 farms had higher scores than those belonging to both the Conventional and the Organic 1 groups. This reason was the higher proportion of wooded area in Organic 2 farms. Finally, Organic 2 farms had the best scores with regard to both the use of autochthonous breeds and the integration of different livestock species.