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Soil desiccation is becoming more and more serious in hilly areas of the Loess Plateau, which has become an important factor restricting ecological restoration and reconstruction in the region. To find a solution to the ecological problem of dry soil remediation, a large-scale underground soil column with depth of 1000cm was planted in the field. Totally nine typical mulches were used on the surface of soil columns, separately for planting Robinia pseudoacacia, alfalfa, Caragana korshinskii, jujube and Poa pratensis, and covering stones, branches, ground cloth and white film. Taking bare soil column as control. Through the analysis of continuous observation data from 2014 to 2018, it was found that under natural precipitation conditions, infiltration depth of Robinia pseudoacacia, alfalfa, Caragana korshinskii and jujube was decreased to 100cm, after the second year of the experiment, the soil moisture in column was in a negative growth state. In the fourth year (2017), the water content of 1000cm soil column was reduced by consumption, and the drying degree of the whole soil column was deepened, among them, that planted Robinia pseudoacacia was the most heavy, and that planted jujube was the lightest. Soil moisture in columns of jujube below 300cm was not increased or consumed. The infiltration depth of Robinia pseudoacacia could reach 300cm, the water consumption during the experiment was slightly less than that of the current year precipitation, which can alleviate the drying soil within 300cm. The maximum restoration depths of covering stones, branches, ground cover and white film were 280cm, 300cm, 580cm and 600cm during the experiment, respectively. Until the fifth year, the mitigation depth of soil moisture covered with stones and branches reached 700cm,and that covered with ground cover and white film reached 1000cm. Covering white film was the best of all. Under natural precipitation, the soil moisture mitigation depth of bare soil column reached 520cm, and restoration depth reached 240cm.