Effect of brackish water irrigation on the movement of water and salt in salinized soil

Abstract

In China, fresh water resources are scarce, while brackish water resources are abundant. Reasonable utilization of brackish water is one of the important measures to alleviate the contradiction of water shortage. In order to study the effect of brackish water irrigation on water and salt transport in saline-alkali soils, one-dimensional brackish water infiltration experiments of soil columns were conducted. The influence of brackish water with different salinities on water and salt transport in salinized soil was compared and analyzed. The results showed that under brackish water irrigation, the Kostiakov model could better simulate the change in soil infiltration rate with time, the soil infiltration capacity had a positive response 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, Na+, and Cl− removal is different, which are inversely proportional to the degree of salinity; with the increase in the salinity of irrigation water, the water salt content and the concentration of Na+ and Cl− increased gradually, but the difference in the desalination zone was not obvious. Therefore, brackish water irrigation has a certain effect on the distribution of water and salt in saline soil.

Keywords

• brackish water
• water and salt movement
• mineralization degree
• salinized soil