Abstract
Agricultural field of arid regions would be exposed to the risks of water scarcity and soil degradation, including salt accumulation. Suitable methods and schedules of irrigation are required to avoid these problems. This study examines the ability of an arranged irrigation method (“2 Depths”: Subsurface irrigation at two depths) in sandy soil. As a first experiment, numerical simulation was conducted to compare the soil water movement with “2 Depths” and with the traditional subsurface irrigation method (“1 Depth”). As a second, field experiment was implemented to measure the dry mattars, water use efficiencies and evapotranspirations of sorghum and the distributions of water and salts in the soil with “2 Depths” and with “Sprinkler” irrigation using saline water. Results of numerical simulation showed that “2 Depths” could increase soil moisture and make soil water distribution uniform. The growth and water use efficiencies of sorghum with “2 Depths” are greater than that of “Sprinkler ”. It was concluded that “2 Depths” is advantageous to save irrigation water and to grow plants.
