Simulating Crop Yields, Soil C N, and Water Dynamics in Long-Term Fields with Diversified Climate Conditions.

Sustainable fertility management and high yield productivity are two of the most important objectives in long- and short-term experiments and they can be assessed by simulation study. This presentation showed our current progress on simulation studies on crop yield, soil C N, and water dynamics in long-term fields with diversified climate conditions. The DSSAT (Decision Support System for Agrotechnology Transfer) v4.6 model was used together with the CENTURY-based soil model for the simulation. Four long-term field simulations were presented to illustrate the effects of crop yield, soil organic C N, soil nitrate N leaching on fertilizer applications and crop rotations. The studies included: (1) simulation of long-term maize yield and nitrogen dynamics in southwestern Ontario, Canada using the DSSAT-CERES-Maize model, (2) modelling crop yield, soil water content and soil temperature for a soybean-maize rotation under conventional and conservation tillage systems in Northeast China, (3) simulation of long-term maize yield, soil C, N dynamics in northeastern China using DSSAT and CENTURY-based soil model, and (4) simulation of long-term spring wheat yields, soil organic C, N,  and water dynamics using DSSAT-CSM in a semi-arid region of the Canadian prairies.

Keywords:Maize, Wheat, Long-term experiment, DSSAT model, soil organic C, Nitrogen leaching