Abstract:
Knowledge of the law of soil water movement and SPAC continuum water flux in cotton fields under drip irrigation with the common style of one mulched with six rows in the Xinjiang arid region is of great significance to realize agricultural water-saving irrigation. In this study, soil water numerical model is built with the Hydrus-2D and calibrated with the experimental data to discuss water flux in cotton field SPAC continuum under mulched drip irrigation. The results show that under the periodic irrigation a divergent curved surface of zero flux occurs at a depth of 50-70 cm below the land surface. During the whole simulation period, irrigation is the main source of inflow water, accounting for 87.6% of the inflow water. More than 70% of the inflow water is consumed by cotton, while soil evaporation and deep percolation account for only 8.2% and 20.8%, respectuvely. The utilization efficiency of agricultural water is 85.2%. The simulation results suggest that the current drip irrigation with the style of one mulched with six rows can effectively reduce invalid evaporation and deep percolation and improve the utilization efficiency of irrigation water resource.