Soil erosion has environmental and socioeconomic significances due to loss of a natural resource. Many of the soils in drylands are characterized by bare surfaces that are exposed directly to water and wind impacts. The ability of the topsoil's to resist erosion depends on their physicochemical properties. Loess soils cover about 10% of the earth's land surface yet they are among the most fertile soils and widely used for agricultural activities. However, these soils are currently or potentially subjected to erosion and dust emission due to rapid environmental changes. The aim of this study is to quantify topsoil characteristics and their spatio-temporal variability in response to seasonal and inter-annual climatic variations and anthropogenic activities. This will allow a better understanding of the topsoil structure processes and thus the potential for erosion in space and time.