Characterizing and Estimating Soil Evaporation in Taklimakan Desert Highway Shelterbelt

Soil evaporation is an important component of water consumption of the Taklimakan Desert Highway Shelterbelt.Micro-Lysimeters were used to measure soil evaporation within an irrigation cycle at different distances from the trees drip-irrigated with saline water.Meanwhile,the relationship between soil evaporation and water surface evaporation was analyzed,and soil moisture evaporation was estimated through one-dimensional adjustment processing.The results show that a spatial-temporal variation pattern of soil evaporation can be clearly identified in the shelterbelt: at the starting stage,the order of soil evaporation was tree base 50 cm from tree base 100 cm from tree base;and after the 5th day,the order was 50 cm from tree base tree base 100 cm from tree base.Soil evaporation in the shelterbelt decreased with soil water contents.The estimation shows that annual total soil evaporation of the shelterbelt will be approximately 2.63×106 m3 with drip-irrigation using saline water,accounting for 21.43% of total irrigation volume,and soil evaporation in a growing season accounts for 92.28% of annual soil evaporation.As soil evaporation results in such a high amount of water loss,appropriate measures may be required for reducing soil evaporation and improving water use efficiency.