Boosting soil health and profitability with cereal rye in Midwest crop-livestock systems under future warming

Abstract

Maintaining agricultural productivity and soil health in the U.S. Midwest amid changing weather patterns is a critical challenge. Using a system-dynamics model previously calibrated and validated against 2002–2022 Iowa data, we conducted the first century-scale (2023–2122) evaluation of four agricultural production systems: conventional corn–soybean cropping with/without rye cover crops (CwCC, CwoCC), and integrated crop–livestock systems with/without grazed rye cover crops (ICLSwCC, ICLSwoCC), under intermediate and high-temperature trajectories. Under the high-temperature scenario, cropping-only systems and ICLSwoCC reach peak farm wealth in 60–70 years, then stagnate or decline, while environmental quality steadily deteriorates. In contrast, ICLSwCC sustains strong wealth accumulation and the highest environmental scores for the entire 100 years, driven by temperature-stimulated rye biomass that supports larger herds (~8.2 million cow-calf pairs versus ~925,000 currently) and enhanced manure nutrient cycling. System rankings remain consistent under the intermediate scenario, though absolute divergences are smaller. Labor–leisure trade-offs persist in both ICLS variants. These exploratory scenarios indicate that only ICLSwCC simultaneously maintains long-term profitability and soil health under substantial temperature increase, making it the most resilient strategy among those examined for the U.S. Corn Belt.