Calibration/Validation of the Maize Growth Simulation Model "Cornf" For Southern Region of Germany

Authors: Sevilay TOPÇU

Abstract: During the last decade there has been considerable advancement in the modelling of plant growth. The dynamic deterministic corn (Zea mays L.) model, CORNF has been developed for this purpose. However, calibration and validation is required for the model before applied in each different geographical region. Therefore, this research was carried out to evaluate the corn model CORNF under the environmental conditions of South Germany and to perform sensitivity analysis. The CORNF model simulates the soil water balance, plant growth, and plant phenology. Sensitivity analysis indicated that the CORNF model required an accurate input for the maturity class. Simulated above-ground dry matter and grain yield varied about ± 10 % when the maturity class was changed by one group, under both water stress and non-stress conditions. A ± 20 % change in the size of the first leaf resulted in a ± 5 % change in the simulated yield and biomass, under both stress and non-stress. The CORNF model overestimated above-ground dry matter by 11,7 % and 6,3 % for 1989 and 1990 respectively, and grain yield was underestimated by 26 % for 1989. Using the CORNF model proved to be difficult at the calibration owing to minor input-data. Because of this the CORNF model can be used as a forerunner for the other detailed corn models.

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