Evaluating innovative scenarios in partnership to enhance mixed crop-livestock farms sustainability

Mixed crop-livestock farms are regaining interest worldwide as a way to reduce environmental problems while allowing a productive and economically viable agriculture. However, these farms have been regressing in Europe. This study aims at evaluating scenarios including technical innovations that could enhance sustainability of mixed crop-livestock farms. Scenarios were defined through a participatory process with farmers and other stakeholders of the Coteaux de Gascogne, a French unfavoured area where crop-livestock farms still exist. Technical innovations were selected in line with two farmer adaptative strategies that allowed mixed crop-cattle farms to last over the long term: 'maximizing farm autonomy' and 'diversifying productions'. We adapted the whole farm simulation tool CLIFS (Crop Livestock Farm Simulator) to evaluate each scenario along with two farmers. CLIFS calculates feed and manure balances, based on characteristics of animals and crops systems within the farm, and economic results. Innovative scenario 'maximizing farm autonomy' was based on sowing forage legumes between two cash crops to achieve autonomy for herd feeding while maintaining soil fertility. Innovative scenario 'diversifying productions' was based on fattening and selling heifers in a short chain. Implementing these innovations allowed an increase of the overall gross margin per hectare of cultivated area by respectively 8.9% and 17.1%. These two scenarios did not offset the drastic shocks resulting from two contrasted political and economic futures: (1) heightening of the current globalisation trends; and (2) political and market incentives for a relocation of production and consumption. Political support would be needed to maintain mixed crop-livestock farms. This approach allows to strongly involve local actors through collective brainstorming on future adaptative strategies. (Résumé d'auteur