Optimization of the Green and Ampt parameters for a conceptual model of rainfall-infiltration-runoff.

摘要

Subsurface runoff and infiltration are generally modelled separately. A conceptual global model (of 2 reservoirs) simulating surface runoff coupled with the Green and Ampt (1911) equation was developed. Nineteen experiments were carried out in the laboratory for different rain intensities and different initial soil moistures. The experimental measurements were fitted to the Green and Ampt infiltration model. Data from these experiments were used for the optimization of the rainfall-infiltration-runoff model parameters. A synthetic calibration of the model was also realized for 9 different cases. The application of the Simplex method (Nelder and Mead 1965) for model parameter optimization diverged with both measured and synthesized data. This divergence was due to the objective function's complex shape and the interactions between model parameters. K/Ks (where K is the hydraulic conductivity of the soil, and Ks the hydraulic conductivity of the soil at saturation) was equal to 0.62, which is close to the value found by Bouwer (1969).