9Zuzel J F, Allmaras R R, Greenwalt R. Runoff and soil erosion on frozen soils in northeastern Oregon [ J ]. Journal of Soil and Water Conservation, 1982, 37(2) :351 -354.
10Chen# C, Payne W A . Measured and modeled unsaturated hydraulic conductivity of a Walla Walla silt loam [ J ]. Soil Science Society of America Journal, 2001, 65 (5) :1385 - 1392.