Abstract: In an oasis irrigated area, a field experiment of wheatcorn intercropping was carried out under different irrigation levels and irrigation patterns so as to determine the effect of alternative irrigation on water consumption of crops and soil evaporation, and the main factors related to water consumption of crops and soil evaporation were investigated. The purpose of this research was to provide the academic bases for reducing the evapotranspiration (ET) of intercropping and optimizing the irrigation technology. Results showed that the ET of wheatcorn intercropping varied in a range of 12.7%-20.1%, it was higher than that of the weighted average ETs of sole cropping wheat and corn, and alternative irrigation could be used to decrease the ET of intercropping compared with the conventional irrigation. Intercropping could be used to increase the daily average soil evaporation (E) by 9.19%-13.6% compared with that of the weighted average of sole cropping systems, and the alternative irrigation could be used to decrease the E of intercropping by 10.1% compared with the conventional irrigation. Compared with the sole cropping wheat and corn, the E/ET of intercropping was significantly increased, and to control E might be an effective way to improve available soil moisture in intercropping. The high ET of intercropping was mainly caused by low leaf area index (LAI) and high leaf area duration (LAD). Compared with conventional irrigation, the alternative irrigation could be used to decrease the soil moisture content in topsoil of intercropping, and it was beneficial to decrease soil evaporation.

Key words: