Analysis of soil moisture condition under different land uses in the arid region of Horqin sandy land, northern China

摘要

Land use plays an important role in controlling spatial and temporalvariations of soil moisture by influencing infiltration rates, runoff andevapotranspiration, which is important to crop growth andvegetation restoration in semiarid environments, such as Horqin sandy land in north China. However, few studies have been conducted comparingdifferences of dynamics of soil water conditions and the responses of soilto infiltration under different land use types in semiarid area. Fivedifferent land use types were selected to analyze soil moisture variationsin relation to land use patterns during the growing season of 2 years.Results showed that soil moisture condition was affected by different landuses in semi-arid sandy soils. The higher soil moisture content amongdifferent land uses was exhibited by the grassland, followed bycropland, poplar land, inter-dunes and shrub land. The temporal variationsof soil moisture in different land uses were not always consistent with therainfall due to the dry sequence. Moreover, soil water at the surface, in the root zoneand at the deep soil layer indicated statistical differences for different types of landcover. Meanwhile, temporal variations of soil moisture profile changed withprecipitation. However, in the deep soil layer, there was a clear lag inresponse to precipitation. In addition, seasonal variations of profile soilmoisture were classified into two types: increasing and waving types. Andthe stable soil water layer was at 80–120 cm. Furthermore, the infiltrationdepth exhibited a positive correlation with precipitation under all landuses. This study provided an insight into the implications for land andagricultural water management in this area.