Soil Saturated Hydraulic Conductivity and Its Influential Factors in Southwest Karst Region of China

The soil saturated hydraulic conductivity in different vegetation degeneration type and its influential factors in southwest karst region of China were studied.The results showed that the soil saturated hydraulic conductivity in different vegetation degeneration type had obvious discrepancy,and it was ranked as follows: forest soil,low-growing bushes soil,farmland soil.The range of the undisturbed surface layer's saturated hydraulic conductivity was between 27.2×10-4 and 50.8×10-4 cm/s.The disturbed surface layer's saturated hydraulic conductivity was between 0.27×10-4 and 1.53×10-4 cm/s.Soil bulk density,soil porosity,the soil organic content and soil particle composition were the important impact factors to soil saturated hydraulic conductivity.The factor analysis showed that soil porosity and soil texture were the major factors to the undisturbed soil saturated hydraulic conductivity.But soil porosity was the dominant impact factor of the disturbed soil saturated hydraulic conductivity in karst region.