Enabling circularity in grain production systems with novel technologies and policy

Introduction: There is an urgent need to transform unsustainable "linear" grain production systems in the United States (U.S.) and other countries like China, Brazil, Argentina, Canada, Russia, Australia and Europe, into more circular and sustainable systems to address the simultaneous challenges of resource depletion, environmental degradation, and the growing global demand for food under the threat of climate change. Objectives: In this perspective, we survey the current state of circularity of U.S. grain production, and discuss how we can transform the systems into more circular systems. Results: Specifically, we lay out a vision of circular grain production enabled by novel digital, mechanical, and biological technologies that allow closing loops of nutrient and energy flows within the farm, through the optimization of land-use choices and crop management. We also examine market-and policy-based mechanisms that could incentivize the widespread adoption of these key technologies.