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With the decrease of irrigation water in Hetao Irrigation District year by year, the salt input into the irrigation district can not be effectively drained. As a result, the salt can only be redistributed in the irrigation district. Based on field measurement and laboratory experiment, the temporal and spatial variation characteristics of the soil profile，different soil layer and groundwater solute were analyzed by using geostatistics and solute dynamics methods in the cultivated land-wasteland-lake system. The soil salinity was estimated in different periods and the effect of groundwater depth on soil salinity were revealed. The results showed that a large amount of salt in the cultivated land was transported into wasteland with the groundwater during the irrigation period. Before autumn irrigation, the accumulated salinity of the wasteland was two times of that of cultivated land. After autumn irrigation, the desalination amount of wasteland was three times of that of cultivated land. In the whole growth period, the salt in soil of 1m cultivated land still accumulated 56%. The salt was not completely discharged after autumn irrigation, and the desalination rate was 44%. There was slight salt accumulation in deep soil layer. The accumulated salt was 63% in 1m wasteland soil and the desalination rate was 62% after autumn irrigation. The accumulated salt in soil of 1m wasteland was 377705kg/hm2. The salt content of 20~100cm wasteland recharged by groundwater was 17985kg/hm2, accounting for 5% of all the accumulated salt. The salt content of 0~20cm soil was increased by 202395kg/hm2, accounting for 54% of all the accumulated salt. The salt content of the deep soil layer transferred by groundwater from cultivated land to wasteland was 114015kg/hm2, accounting for 30% of the accumulated salt. the salt content from horizontal infiltration of cultivated land to wasteland was 43305kg/hm2, accounting for 11% of the accumulated salt. The spatialtemporal distribution of groundwater and lake salt was strip and patch, which had greatly spatial similarity. Lake became a salt storage area. Measures should be taken to decrease the depth of groundwater by 0.2m. The groundwater depth in the study area should be controlled between 1.7m and 2.3m. The results can provide theoretical basis for water and salt transport in irrigation area.