Understanding the benefits of herbivore system diversification : lessons from French Massif central

Herbivore farming systems in the Auvergne region (north of the French Massif central) are highly diverse as the result of history and strong pedoclima tic contrasts. Among agroecological principles, system diversification is assumed to increase farm economic and environmental performances, but we still lack knowledge on how to manage these systems. Here we report the result of farm surveys that were conducted across a range of systems from the same areas: beef-crop, mixed cattle-sheep and cattle-horse systems. We also use a bioeconomic optimization model to provide further information on mixed beef-dairy systems, including their carbon footprint and resilience to market hazards. Grazing two livestock species on the same farm leads to a better utilization of grasslands and can dilute parasite burden, and doing this decreases inputs and production costs. Integrated crop-livestock management also decreases feeding costs, and so production costs and farm carbon footprint. Equipment and housing costs were reduced in mixed cattle-sheep systems, where mixed farming also buffered farm income variability. Equipment largely differ between the beef and crop enterprises, which limits economies of scope in beef-crop systems. Buffer capability was reduced in mixed beef-dairy systems where both enterprises produce meat and thus rely on the same market. Finally, workload was more evenly distributed along the year in mixed cattle-sheep systems. Farmers also mentioned the pleasure of varied work and flexibility of work organization in mixed systems as a matter of satisfaction. We conclude that in spite of various amplitudes in the effects observed, the diversification of herbivore farming systems can enhance system efficiency and increases options for adapting to change, and that this can occur at a constant workload.