Hydraulic Characteristics and Its Impact Factors in Typical Red Soil Region

To understand water storage capacity,varying range of available water in typical red soil more systematically,and undisturbed red soil samples in soil profiles were collected.The soil hydraulic characteristics and impact factors also were studied.The results showed that the range of undisturbed soil saturated hydraulic conductivity was between 1.44×10-3 and 3.45×10-3 cm/s.Its value decreased from top to bottom.The saturated water content,field capacity,wilting water and available water were figured out from the soil moisture characteristic curves.Available water content varied from 0.083 to 0.124 cm3/cm3,and surface soil layer was the largest one.There were some correlations between hydraulic characteristics and its impact factors,such as bulk density,soil texture,organic matter content and soil structure coefficient.The soil bulk density and porosity were the main impact factors.