关键词: 微咸水;水盐运移;矿化度;入渗试验;盐碱土;

Abstract: In China, fresh water resources are deficient but brackish water resources are rich.Reasonable utilization of brackish water is one of the important measures to alleviate the shortage of water resources.In order to study the effect of brackish water irrigation on water and salt transport in saline-alkali soils, a one-dimensional soil column brackish water infiltration experiment was conducted.The effects of brackish water with different salinity degrees on water and salt transport in saline-alkali soils were compared.The results showed that the Kostiakov model could better simulate the change of soil infiltration rate with time in brackish water irrigation; the soil infiltration capacity was directly proportional to the salinity of irrigation water; there was a good linear relationship between cumulative infiltration and the wetting front distance.Under different salinity conditions, the depth of soil desalination was about 15 to 18 cm, the depth of removing Na+ was 15 to16 cm, and the depth of removing Cl- was 22 to 23 cm, all which were inversely proportional to the level of salinity.With the increase of the salinity of irrigation water, the contents of soil moisture, salt, Na+ and Cl- in each soil layer gradually increased in the salt accumulation area, but the difference was not obvious in the desalination area.The results showed that brackish water irrigation has a certain effect on the distributions of water and salt in saline-alkali soils.

Key words: brackish water; water and salt transport; mineralization degree; infiltration experiments; saline-alkali soils;