Spatial variability of soil moisture on steep slopeland in loess hill region

It is very meaningful for making the most of soil moisture to probe into spatial distribution of slopeland soil moisture in the Loess Plateau. Soil samples were taken from eroded steep slopeland in loess hill region. Soil water content of a depth of 200 cm at 20 cm intervals was determined in the laboratory. The data were processed by SPSS (8.0) software. The results show that soil moisture of all soil layers but 180～200 cm are normally distributed. Soil water content on the steep slope is high in 0～20 cm soil depth, low in 20～100 cm, and high in 100～200 cm. Variation of soil water content of 20～120 cm soil depth is much larger than that of both 0～20 cm and 120～200 cm, especially along horizontal direction slope. Soil water content increases at first, then it keeps flat or reduces along longitudinal direction. Though both longitudinal and horizontal slope position affect distribution of soil moisture, longitudinal direction has more significant influence on soil moisture than horizontal direction. Geostatistics is not able to effectively analyze spatial variability of soil moisture on the steep slope with shallow gully in the Loess Plateau.