*3.3. Evaluation of AquaCrop Model Performance in Simulation Wheat Grain Yield and Above-Ground Biomass*

Figure 3 shows the comparison between the Mexicali cultivar's final yields and aboveground biomasses observed at Setif experimental site during the three tests growing seasons: 2010/2011, 2011/2012, and 2012/2013, with respect to those simulated by AquaCropin these same growing seasons. Thus, according to Figure 3a, the Mexicali cultivar's yields were simulated with good precision for the three years. However, as shown in Figure 3b, AquaCrop overestimates the simulation of the above-ground biomass for the 2012/2013 s growing season. This could be due to an error in the biomass measurement at the field test. Generally, the averages of statistical indicators of the model's performance, for the three growing seasons were better in predicting yield (RMSE = 0.41 tha<sup>−</sup>1, NRMSE = 8.81% and d = 0.80), than in prediction above-ground biomass (RMSE = 2.25 tha<sup>−</sup>1, NRMSE = 21.65% and d = 0.54) (Table 4). In Brazil, Rosa et al. [39] validated the AquaCrop model to predict wheat grain yields with an estimated RMSE = 0.6 tha−<sup>1</sup> and a Willmott agreement index of (d) ≥ 0.80.

**Table 4.** Comparison of Mexicali cultivar's yields and above-ground biomasses observed and simulated by AquaCrop in the 2010/2011, 2011/2012 and 2012/2013 growing seasons.

