Puntel, L. A., Sawyer, J. E., Barker, D. W., Dietzel, R., Poffenbarger, H., Castellano, M. J., et al. (2016). Modeling long-term corn yield response to nitrogen rate and crop rotation. Front. Plant Sci. 7, 1630. doi:10.3389/fpls.2016.01630.
Quantify model prediction accuracy before and after calibration, and report calibration steps
Compare crop model-based techniques in estimating optimal N rate for corn
Utilize the calibrated model to explain factors causing year to year variability in yield and optimal N
We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn [Zea mays L.] and soybean [Glycine max L.] yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. We evaluate APSIM the model performance of a “blind phase” (uncalibrated model) where management and cultivar information were used, and a “calibrated phase” (calibrated model) where crop yield and soil organic carbon (SOC) data were provided into the model.