Spatial Contribution of Environmental Factors to Soil Aggregate Stability in a Small Catchment of the Loess Plateau, China

Soil aggregate stability and erodibility are the influential factors governing soil resistance to water erosion. The interactions among stability, erodibility, their influencing have not been fully explored. We collected samples from 0–10 cm 10–20 layers in Zhifanggou watershed. Then, major contributors how properties, environmental land use contributed them were explored by using partial least-squares regression path analysis, respectively. results showed that included slope, organic carbon (SOC), elevation, percentage of landscape area farmland (PLAND_F) grassland (PLAND_G), surface temperature difference between seasons (ΔLST), topographic wetness index (TWI), pH, amorphous iron (poorly ordered forms iron, Feo), calcium carbonate (CaCO3). In which, SOC, elevation most important mean weight diameter (MWD) water-stable aggregates greater than 0.25 mm (WSA>0.25) had a direct contribution MWD, WSA>0.25, K factors. PLAND_F PLAND_G significant indirect those three indices affecting slope. Meanwhile, effects Feo, CaCO3 on WSA>0.25 should also be underestimated. For MWD there was significantly higher effect types composition hydrothermal conditions. factors, PLAND’s still ΔLST TWI, but they all significant. other including CaCO3, indirectly affected SOC. However, contributions properties increased as layer deepened.