Development And Evaluation Of A Water Flow And Solute Transport Model For Furrow Fertigation With Surge Flow

One of the important factors in fertilizer application efficiency in surface fertigation is the shape of inflow hydrographs. In this research, a fertigation model is developed to analyse the effect of surge flow on furrow fertigation. Saint-Venant equations and the advection-dispersion equation were used to estimate water flow and solute transport characteristics, respectively. The field experiments, including different fertigation treatments with surge flow, were conducted to calibrate and evaluate the developed model. Most of the water and nitrate losses occurred through runoff; water losses through runoff ranged from 13.8 to 33.4%, while fertilizer losses varied between 5.1 and 47%. Water and nitrate losses in the second fertigation experiments were higher than those in the first due to the reduction of the surge effect. A comparison between simulated and observed data shows appropriate accuracy of the developed model; the root mean squared error (RMSE) index for nitrate and water runoff losses was 8.4 and 12.1%, respectively. Fertigation during all advance surges was recognized as the desirable option in furrow irrigation with a surge flow. (c) 2020 John Wiley & Sons, Ltd.