Distribution and simulation of saturated soil hydraulic conductivity at a slope of northern Loess Plateau

To provide a theoretical basis for simulating soil hydraulic processes,classical statistics and geo-statistics were used to characterize the spatial distribution of saturated soil hydraulic conductivity( Ks) at a slope scale in the northern Loess Plateau. Furthermore,the first order autoregressive state-space model was applied to simulate the distribution of Ks. The magnitude of Ksvariability was moderate according to the coefficient of variation. The degree of spatial dependence was moderate with range of 42 m. Bulk density,sand content,silt content,and clay content were auto-correlated. Cross-correlation existed between Ksand other factors at different lag distance. Bulk density and soil particles were the key factors to affect the spatial distribution of Kson the sloping land. A combination of bulk density and soil particles was the best to explain the spatial variation of Ks( R2> 0. 9). The first order autoregressive statespace model is suitable for simulating the Ksdistribution at a slope scale.