Evaluation of AquaCrop to simulate saffron (crocus sativus l.) yield under different water management scenarios and zeolite amounts

This research was conducted to evaluate AquaCrop to simulate saffron (Crocus sativus L.) yield and biomas under water management and zeolite amounts using collected data during 2013-2015. Treatments consisted of irrigation (traditional: I1, deficit irrigation as 70% moisture depletion: I2 and full irrigation: I3) and zeolite rates (0: Z0, 0.5: Z1, 1: Z2 and 2: Z3 as weight percentage) divided into two groups. The first group (consisted of 70% data) was used to calibrate and the second one (consisted of 30% data) was considered to validate the accuracy of AquaCrop. The highest differences between measured and simulated data was found in traditional irrigation. Mentioned differences in some treatments with zeolite decreased. Nevertheless, there was no significant relation between those results. RMSE, MBE and NRMSE values for saffron yield were 0.48 (kg.ha-1), -0.21 (kg.ha-1), 0.09, respectively. These values for biomass were 151.9 (kg.ha-1), 74.2 (kg.ha-1) and 0.13, respectively. The aforementioned results showed that AquaCrop had a good accuracy to simulate saffron yield and biomass. Efficiency of the model was found in an appropriate range so that values of EF for calibration and validation stages were 0.32 and 0.42 for saffron yield, respectively, and were 0.99 and 0.99 for saffron biomass, respectively. Regarding the results, AquaCrop had a sufficient precision to simulate saffron yield and biomass under different irrigation and zeolite amounts. As an accurate crop growth model, it is recommended to use this model for simulating saffron yield.