Three types of soil textures(loam,sandy loam,and clay)from corn fields in western Liaoning province in 2021 were selected,along with different precipitation levels(light rain,moderate rain,and heavy rain)for con-tinuous 7 days and every other day for 7 days after that.The relative soil moisture data for 0～50 cm depth was collected.The characteristics of soil moisture recession for different precipitation levels,soil textures,and soil depth recession coefficients(K)during the corn growing season in this region were analyzed,and a soil moisture predic-tion model was constructed.The results show that the soil moisture recession process in corn fields of western Lia-oning can be divided into three stages:rapid recession,slow recession,and stagnant recession.The average reces-sion rate during the rapid recession stage for the three soil textures was 7.21 mm·d-1,with clay soil having a 9%-12%higher rapid recession rate than other soil textures.There were no significant differences in the slow recession and stagnant recession rates among different soil textures.The K value of the shallow layer(10～20 cm)was sig-nificantly smaller than other soil layers and had the largest dispersion.The fluctuation range of K values in the 50 cm soil layer increased significantly under heavy rainfall conditions.There was a significant negative correlation between K values and precipitation(R=-0.92).Under the same rainfall level,the K value of clay soil was12%-20%lower than that of loam and sandy loam.The monthly variation of K values showed the highest in March,lowest in late August,and rebounded to a relatively high value in late November.Based on the soil moisture bal-ance equation,a soil moisture recession model was constructed.The simulation accuracy was best for light rain lev-els,and the simulation results for shallow soil layers were better than those for deep layers.
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