Background In order to reveal the infiltration characteristics and influencing factors of typical urban soils in semi-arid areas of western Liaoning, taking Fuxin city located in the western Liaoning region as an example, the infiltration capacity of urban soil in Fuxin city and its influencing factors were studied, from the angle of the soil infiltration to discuss the reason of urban waterlogging in western Liaoning flood season.

Methods The method of combining the field double ring infiltration with the indoor analysis was used to systematically analyze the physical and chemical properties and infiltration characteristics of eight different types of urban soils, Using Horton model, Kostiakov model and Philip model, the urban soil infiltration was fitted by Origin 9.1 software.

Results The bulk density of urban soil in Fuxin is 1.23-1.44 g/cm³, and the bulk density of green land is the smallest. The overall soil shows the characteristics of low organic matter content, high sand content (all above 72%) and poor soil viscosity. Compared with the original soil in the suburb, the soil compactness and texture in urban area are significantly different. The stable infiltration rate of remolded soil of park green space is 2.04 mm/min, which is not significantly different from the stable infiltration rate of primary soil in suburb, which is 1.15-4.00 times of that of other types of urban soil. The stable infiltration rate of different types of urban soil is negatively related to bulk density, positively related to total porosity. The goodness of fitting regression models for different types of urban soil infiltration process is Horton model > Kostiakov model > Philip model, Horton model can be used as the best model to simulate and predict the urban soil infiltration process in Fuxin. In Fuxin city, the distribution of stable infiltration rate grades of urban soil is relatively concentrated, with slow and medium infiltration rate grades accounting for 12.5% and 75.0% respectively, and the infiltration capacity of urban soil is weak.

Conculsions Human activities lead to compaction of urban soil to different degrees, change the soil structure, and weaken the infiltration capacity of urban soil. The soil infiltration classification in Fuxin city was mainly in the slow and medium grades, and the soil infiltration capacity is weak, which is one of the reasons for urban waterlogging in flood season. Increasing the area of urban green space and enhancing the management and maintenance of urban green space to improve the soil structure is the key to improving the function of urban soil water conservation.