[Simulation of AquaCrop model and management practice optimization for dryland maize production under whole plastic-film mulching on double ridges].

In order to study the applicability of AquaCrop model for simulating dryland whole plastic-film mulching in double ridges cultivation mode and to find the best agronomic management measures, the data of nitrogen gradient test in 2014 and 2015 were selected to validate the variety and stress parameters in the model. The change trends of yield were simulated under different mana-gement measures. The results showed that the root mean square error (RMSE), normalized root mean square error (NRMSE) and the compliance index (d) of the measured and simulated production for all treatments were 717 kg·hm, 10.0% and 0.96, respectively, the RMSE, NRMSE and d of the total biomass were 951 kg·hm, 6.5% and 0.98, respectively, which indicated that the cultivation characteristics of the whole plastic-film mulching on double ridges maize in the dryland could be well reflected. The best fitting degree was 270 kg N·hm from dynamic simulation analysis of canopy cover degrees and biomass, and with the increase of N stress, the simulation accuracy gradually declined. The best sowing time of the whole plastic-film mulching on double ridges maize in the middle part of Gansu Province was from late April to early May, the seeding density was 45000-65000 plants·hm, the growth period was 130-145 days, and the nitrogen application rate was 240-280 kg·hm. The results of this study had a certain reference value for the application of AcquaCrop model in arid region of Gansu, and would contribute to the transformation and popularization of agricultural cultivation techniques.