Application of HYDRUS-1D model for research on irrigation infiltration characteristics in arid oasis of northwest China

Irrigation is vital to agriculture and economic development, especially in arid areas. It is essential to study the characteristics of water infiltration with respect to understanding of water balance information and to provide scientific theory for rationally utilizing water resource. In this study, a HYDRUS-1D model was established to simulate the process of soil water infiltration after a field infiltration experiment conducted in Yaoba Oasis, and the measured water content data were used to calibrate and validate the model. Results showed that average correlation coefficients of simulation results were up to 0.9, and relative error and root mean square error were 6.11% and 0.015 cm3 cm−3, indicating that the HYDRUS model has a higher degree of accuracy and could be used to simulate the procedure of soil water infiltration in Yaoba Oasis. During 2015 season, consumption of evaporation and transpiration was 429 and 386 mm, respectively, and transpiration was only 67% of potential transpiration, which caused that the yield of corn was affected by water stress. Contrarily, due to high sand content and inappropriate irrigation regime, the amount of invalid leakage waste was up to 581 mm, accounted for 40.9% of the total infiltration. The simulation of different irrigation regimes found that increasing the irrigation times and controlling the single irrigation amount properly could both save water resource and improve root water uptake amount.