Study on soil water and salt movement and its effect on wheat production under saline water irrigation in North China Plain

In order to explore a scientific and rational utilization way of the saline groundwater resources in North China, the effects of saline groundwater irrigation on soil water-salt movement and wheat production was studied by the field experiments of saline water irrigation for winter wheat, with both saline water and fresh water irrigation.The results showed that the water movement depth of fresh water irrigation side was deeper than that of salt water irrigation side, and the soil water content of fresh water irrigation side was higher than that of salt water irrigation side at the same depth. It can be inferred that salt water irrigation affects soil infiltration and soil water holding capacity to a certain extent. With the continuous irrigation, salt accumulated in the surface layer(0~0.2 m)and the deep layer (0.6 m~1.2 m) of the saline water irrigation side.The salt content accumulated differently at different depth of the soil profile in the whole growth period, and it reached a peak value of 1.6 g/kg at the depth 0.4 m.The effect of fresh water irrigation on salt accumulation was relatively weak, but it would leach salt from surface to deep layer. When the salinity of irrigation water reached 8.69 g/l, the yield of winter wheat reduced by 37.65%. Therefore, when saline water irrigation is carried out, the mineralization degree of irrigation water should be reasonably controlled.