evaluation of the aquacrop model in the simulation of the simultaneous effect of different water regimes and salinity on soybean's productivity and yield in the north of iran

Objective: this study investigates the feasibility of integration using caspian sea water and different fresh groundwater levels for soybean irrigation and performance evaluation of the aqua crop model at the gorgan university of agricultural science and natural resources research field in the golestan province, northern iran. material and methods: irrigation applications comprised irrigation at 75% of field capacity (fc) (i1), 100 % fc (i2), and over irrigation at 125% fc (i3). experiments were conducted during two consecutive seasons. it was done by grain yield (gy), biomass yield (by), and water productivity (wp) under varying irrigation depths and saline water regimes. model efficiency (e), coefficient of determination (r2), root mean square error (rmse), and mean absolute error (mae) were used to evaluate the model performance. results and discussion: the calibration results for (gy) and (by) were in line with observed data, with the estimation error statistics 0.97