Abstract:
The AquaCrop model driven by water was used to study the simulated yield of full film double ridge sowing technology of corn in Dingxi City from 2016 to 2020, and I
1(bare land planting), I
2(narrow film planting with 45% mulching rate), I
3(wide film planting with 81.8% mulching rate) and I
4(full film double ridge planting with 100% mulching rate) were established respectively. The yield superiority and environmental adaptability of the four models were compared and analyzed, The relationship between sowing date, rainfall and soil moisture was obtained. The results of AquaCrop simulation showed that the model was suitable for simulating dry farming in Dingxi City. The Pearson correlation coefficient(r) between the output simulation value and the measured value of I
4 model was greater than 0.91, the root mean square error(RMSE) was 0.1~0.24, the normalized root mean square error(CV(RMSE)) was 1.66%~2.10%, the Nash efficiency coefficient(EF) was greater than 0.9, and the consistency index(d) was greater than 0.94. The average temperature of the best sowing date in Dingxi City was stable at about 15℃(about April 15-25 every year). The yield after sowing was the highest in this period. The yield, aboveground biomass and water productivity of the planting mode I
4 model were 84.01%, 19.79% and 101.13% higher than that of the planting mode I
1 model, 82.26%, 19.74% and 85.47% higher than that of the planting mode I
2 model, and 63.26%, 14.80% and 82.63% higher than that of the planting mode I
3 model, respectively. The total soil water content of I
4 model in dry years was more than 90% higher than that of I
1, I
2 and I
3 models, and more than 80% higher in wet years. From 2000 to 2020, the water consumption was higher than the effective rainfall for seven years, and the water consumption was lower than the effective rainfall for 13 years. The simulation results showed that the water consumption of the full film double ridge sowing technology was equal to the rainfall, and the soil water would not be overdrawn.