Martinez-Feria R.A., R. Dietzel, M. Liebman, M.J. Helmers, S.V. Archontoulis (2016) Rye cover crop effects on maize: A system-level analysis, Field Crops Research. doi: 10.1016/j.fcr.2016.06.016.
The effect of rye cover crop on corn yield, water and nitrate leaching in subsurface drainage is proportional to the amount of rye biomass produced at termination.
We tested the hypothesis by synthesizing experimental, literature and APSIM model results to perform a comprehensive systems level analysis and shed light into the underlying mechanisms by which rye affects corn-based systems in Iowa (Fig. 1). We considered six years of data on soil moisture, soil temperature, water and nitrogen leaching, rye above and below ground biomass and its carbon and nitrogen concentration, corn yields and N uptake at harvest. We supplement these data with 30-yr APSIM model simulations and literature data to develop robust relationships to support deeper understanding and decision making.