Simulation of Crop Productivity for Guinea Grass (Megathyrsus maximus) Using AquaCrop under Different Water Regimes

The perennial herbaceous forage crops’ (PHFC) biomass as bioindustry feedstock or source of nutrients for ruminants is very important from their final utilization point view. In 2022, the AquaCrop-FAO version 7.0 model has been opened PHFC. this context, study aimed to test first time ability simulate canopy cover (CC), total available soil water (TAW), and (B) Guinea grass (Megathyrsus maximus cv. Agrosavia sabanera) under different regimes at Colombian dry Caribbean, South America. included L1—irrigation based on 80% field capacity (FC), L2—irrigation 60% FC, L3—irrigation 50% L4—irrigation 40% L5—irrigation 20% L6—rainfed. AquaCrop uses normalized productivity—WP* (g m−2)—to estimate attainable rate crop growth limitation. WP* was 35.9 ± 0.42 g m−2 with a high coefficient determination (R2 = 0.94). calibration results indicated simulated CC good 0.84, RMSE 17.4%, NRMSE 23.2%, EF 0.63 d 0.91). addition, cumulative simulations were 1.0, 5.13 t ha−1, 8.0%, 0.93 0.98), TAW 0.85, 5.4 mm, 7.0%, 0.56 d= During validation, moderately all (0.78 < R2 0.97; 12.0% 17.5%; 15.9% 28.0%; 0.47 0.87; 0.82 0.97), (0.99 1.0; 0.77 ha−1 3.15 ha−1; 2.5% 21.9%; 0.92 0.99; 0.97 1.0), acceptable (0.70 0.90; 5.8 mm 21.7 7.6% 36.7%; 0.15 0.58 0.79 0.9). provide an basis future research, such estimating production high-producing grasses in tropical environments, yield effects scenarios climate variability, change presented parameterization considering wide range environments grazing variations.