Based variation of electric conductivity in 0~20cm soil layer and water density in 0~120cm soil layer, effects of different
regulation measures on water and salt regime of soil under cropping in microplots were studied. Patterns of the dynamic variation of water and salt regimes and causes of the vairation were also analyzed under continuous cropping in fields. By taking into account the five factors in the
experiment, such as water mineralization degree, times of
irrigation, irrigation rate, organic manure application rate and crop coverage, differences in courses and mechanisms of the variation of water and salt in the soil between different stages were explored. Effects of the influencing factors on soil water and salt movement and their mechanisms were investigated. Weighing analysis of the soil water and salt movements by the experimental factors and integrated factor analysis of the experiment results and indexes were performed. The soil water salt movements during the course of utilizing salt water and barely usable water in irrigation and its mechanism for salinity control were studied. And on these bases, the pattern of the changes in soil water and salt and the mechanism of the action were elaborated.