AquaCrop modelling rainfed maize development in Baijiang soil of the Sanjiang Plain

This study evaluates the applicability of the AquaCrop model for simulating the growth process and yield estimation of rainfed maize in the Baijiang soil area of the Sanjiang Plain. The model parameters of this study and other studies with different climates were compared. The results show that the AquaCrop model effectively simulates the soil moisture content, biomass, and yield of rainfed maize in the Baijiang soil area of the Sanjiang Plain. The root mean square error of observed and simulated soil moisture, rainfed maize biomass, and rainfed maize yield range from 0.80%~1.02%, 0.372~0.995 t/hm², and 0.563~1.04 t/hm², respectively, and the consistency index ranging from 0.878 9~0.990 7, 0.992 7~0.998 9, and 0.982 4~0.988 9, respectively. There are similarities and differences in the calibration of AquaCrop model parameters for maize in different climatic regions. There are significant differences in the calibration values of the Canopy growth index and Canopy transpiration crop coefficient, while the calibration values of Normalized water productivity, Canopy decay index, Maximum canopy coverage, Harvest index parameters are relatively small. In case of sowing time ahead of schedule, the duration reaching the maximum canopy cover was suggested to be properly prolonged for reducing simulation bias.