FAO AquaCrop Model Performance: in Green Canopy Cover, Soil Moisture and Production of Maize at Middle and Lower Reaches Plain of Yangtze River of China

摘要

Crop water productivity models are valuable tools for investigate the crop responses to the water-management strategies and ameliorate the efficiency of water use in agriculture. The objective of this study was to evaluate the performance of AquaCropmodel for maize crop (Zea mays L.) under full, excessive and deficit applications of drip irrigation in semi-humid region of China. The evaluation results emphasized the model accuracy in simulations CC, SWC, B*, Y and WUE with satisfactory performance in full irrigation, and moderate water stressed treatment T2 of 75% of full irrigation. This accuracy declines in circumstances of excessive irrigation T_1 of 125% of full irrigation, and high water stressed T_3 of 50% of full irrigation. The RMSEs and NRMSEs in simulated CC, and SWC for full irrigation, T_1 T_2 and T_3 treatments were 7.3—8.6, 6.3-7.2, 5.4-6.3 and 4.9-5.6% CC, respectively, and 9.4-4.8, 16.1-8.1, 16.4-9.3 and 20.9-13.4% SWC, respectively. Whereas, the Z)-indexand Rr of CC varied between 0.72 to 0.89 and 0.99 to 1.0, while in the SWC varied between 0.54 to 0.83 and 0.48 to 0.96 for the four irrigation treatments. The differences (S.D) in final biomass and grain yield were within the range of 0.23 to 4.45% and 0.30 to 1.46% between themeasurement and simulation. Simulated WUEs of biomass and yield under different irrigation treatments ranged between 6.07 to 6.52 kg/m~3 and 3.07 to 3.16 kg/m~3, AquaCrop's performance trends to underestimate the WUEs of biomass and yield, and emphasizesthat the yield WUE increased linearly with water stress condition increased.