Simulation of fertilization effect on winter wheat yield in Changwu dry highland

In order to determine the suitable level of fertilization and production in dry highland under real time meteorological condition, the WinEPIC model was used to simulate continuous winter wheat yield under different fertilization treatments in Changwu dry highland based on model validation. The validation result shows that correlation coefficients of winter wheat yield between observed and simulated are 0.740, 0.762 and 0.740 respectively for treatments of CK, N and NP, which all reach significant level. Win EPIC model can simulate winter wheat yield precisely under different fertilization treatments. The simulation results indicate that grain yields of the continuous winter wheat under no fertilization, low fertilization, medium fertilization and high fertilization treatments decrease significantly with fluctuation, average yields are 1.055, 1.422, 2.405 and 3.170 t/hm2, respectively. The differences among treatments are significant. Medium and high fertilization treatments are better to increase winter wheat yield. The results can provide scientific basis for sustainable development of winter wheat in Loess Plateau.