Cover crops decrease maize yield variability in sloping landscapes through increased water during reproductive stages

Rolling hill style topography is a common feature of agricultural land throughout the United States. Topographic complexity causes subfield variation in soil resources such as water and nutrients, leading to mosaic high- low-productivity zones that can shift from one year next due weather. Stabilizing yields across these productivity using agroecological methods may improve use efficiency, prevent unnecessary cropland expansion, reduce environmental impact systems. Here, we hypothesized cover crops help nutrient losses increase stability subsequent maize time space. We performed field study evaluate effect cereal rye (Secale Cereale L.) crop on (Zea mays yield at three landscape positions (summit, backslope, toeslope) Central KY 2018–2019, calibrated DSSAT v4.7.0.001 computer simulation program test our hypothesis thirty-year period. Our trial showed pronounced variability different positions, ranging 6.3 Mg ha?1 12.2 toeslope. Model simulations were consistent with results indicated low backslope primarily stress, >10 % reductions 17 out 30 simulated years relative under irrigated conditions where was not limiting. In contrast, toeslope summit experienced stress only 6 years. Growing before reduced frequency raised by 6% (500 kg ha-1) average, 24 (1235 during dry The coefficient all weather 33 26 when followed compared fallow. benefits associated decreased evaporation runoff increased availability anthesis late reproductive phases. Crop model allowed us parse fundamental drivers interaction between complex scenarios. Overall, demonstrates outsized potential stabilize grain rolling landscapes emphasizes value tool for ecological intensification.