ABSTRACT

Mixed farming systems are gaining interest both as a risk management strategy and to apply agroecological principles. This study set out to assess the sustainability of mixed systems compared to their specialized counterparts. The Orfee bioeconomic farm model was used to simulate three mixed farms: beef and dairy, beef and sheep, and cash crop and beef, under 1990–2017 prices and policies in France. Several sustainability criteria were computed at two scales (i) aggregated farm level, to assess whether mixed farms with several integrated enterprises performed better than if these enterprises were managed in specialized farms, and (ii) unit of product or labour to assess whether a product was produced more sustainably and a worker obtained higher and more stable income in a mixed farm. We found that mixed farms had less work peaks, lower global warming potentials and nitrogen balances, lower total production costs, higher and more stable net incomes than if their enterprises were managed in two specialized farms. However, profitability and income variability of the mixed farms were not better than the best performing specialized farm. The consumption of concentrate feed decreased in the mixed livestock farms but increased in the beef-crop farm that degraded feed-food competition.

摘要

混合耕作系统作为一种风险管理策略和应用农业生态原则都受到关注。本研究旨在评估混合系统与其专业对应物相比的可持续性。Orfee 生物经济农场模型用于模拟三个混合农场：牛肉和奶制品、牛肉和绵羊以及经济作物和牛肉，采用 1990-2017 年法国的价格和政策。在两个尺度上计算了几个可持续性标准（i）综合农场级别，以评估具有多个综合企业的混合农场是否比在专业农场中管理这些企业更好，以及（ii）产品或劳动力单位，以评估产品是否生产更可持续，工人在混合农场获得更高和更稳定的收入。我们发现混合农场的工作高峰期较少，与在两个专业农场管理企业相比，它们的全球变暖潜能值和氮平衡更低，总生产成本更低，净收入更高且更稳定。然而，混合农场的盈利能力和收入变化并不比表现最好的专业农场好。混合畜牧场的精饲料消耗量减少，但牛肉作物农场的精饲料消耗量增加，这降低了饲料-食品的竞争。