Effects of salt crust on soil evaporation condition with saline-water drip-irrigation in extreme arid region

Soil salt crust develops widely in the Trim Desert Highway Shelterbelt, and it has significant effect on soil water evaporation process. Field sample analysis and control experiment with Micro-Lysimeters were used to study soil evaporation process affected by salt crust during one irrigation cycle. The results showed that soil evaporation reduced gradually from soil surface downwards, and the evaporation from soil with salt crust was less than that without salt crust; daily evaporation reduced gradually with the decrease of soil water content, daily evaporation from soil with salt crust was higher than that without salt crust at earlier stage and lower at later stage; cumulative evaporation increased gradually, but rate of increment reduced gradually, and cumulative evaporation from soil with crust was less than that without salt crust; inhibition efficiency of salt crust on soil evaporation reduced gradually, but bare land reduced faster than shelterbelt; salt crust can inhibit soil evaporation effectively.