Characterizing Preferential Flow Paths in Texturally Similar Soils under Different Land Uses by Combining Drainage and Dye-Staining Methods

Preferential flow paths have been widely characterized by many visualization methods. However, the differences in preferential under various land uses and their relationships to hydraulic properties remain uncertain. The objectives of this study are (1) characterize (forest orchard) combining drainage dye-staining methods (2) build a connection between hydraulic-related parameters extract proportion from compounding effects matrix flow. experiments were conducted five sandy soils one clay loam situ, including four forest two orchards. A total 47 soil cores, 4 cm height 9 diameter, collected each layer dye-stained for laboratory. Dye coverage hydraulically equivalent macropore (macroporosity, pore size distribution, number macropores) analyzed. results show that volume is partly affected volume. effect macropores on varies distribution. exhibited significant (P < 0.01) correlation with macroporosity (correlation coefficient 0.83). Based value or steady effluent rates, part dye was due surface (resulting both flow) could be identified study. Compared orchards, forestland has more subsoil. Further studies needed quantify 3-D properties.