The author made a simulated leaching soil columns experiment in outdoors

including intermittent leaching and continuous leaching

the purpose was to analyze the improvement effect of saline soil under the combination of different irrigation amount and different irrigation frequency. The results indicated: (1) Under the same irrigation amount

the percolate electric conductivity of intermittent leaching higher than continuous leaching

leaching efficiency of intermittent leaching was higher than continuous leaching from beginning to end. (2) Under the different irrigation amount

the percolate volume of amplified along with the irrigation amount growth

the greater irrigation amount

the better leaching efficiency. (3) The change trend of soil pH value was drop than before after leaching

and it was same of the change trend of soil salt; the greater irrigation amount was

the better the efficiency of alkali removes. In this experiment

leaching efficiency of 15 L points three times is optimal

leaching efficiency was 11.58 g/L

15 L of the surface soil pH values decreased from 8.42 to 8.07. The results can provide reference for the improvement of saline alkali land in arid area and the establishment of water saving irrigation system of maintaing farmland water and salt balance.