Linking arable cropping and livestock production for efficient recycling of N and P

Decoupling of crops and livestock at the farm and regional scales has resulted in reduced soil fertility in some areas and pollution of watercourses in other areas. Here, we discuss how integrated crop livestock systems (ICLS) as an alternative to specialization could influence nitrogen and phosphorus (N and P) cycling in European agriculture. We define three farming system models according to a gradient of integration between crop and livestock from the farm to the landscape scale. The “Complementarity” and “Synergy” models reflect different degrees of integration but in the “coexistence” model, crop and livestock systems are disconnected within a region or local area. We develop two themes for improving N and P management: (1) recycling of N and P through improved management of organic manure to fertilize crops and (2) diversification of crop rotation, including leys, to achieve animal feeding autonomy. We finally suggest some guidelines for further research for developing agronomic solutions for better nutrient use in ICLS and discuss options for improved knowledge exchange through actor-oriented solutions.