Role of the preferential flow at rock–soil interface in the water leaking process in near-surface fissures filled with soils in the karst rock desertification area

Abstract Soil preferential flow infiltrating rapidly through the rock–soil interface is an important hydrological process in karst rocky desertification area. However, how does water leakage near-surface fissures, especially those filled with soil, proceed? The role of at fissures on still puzzles us. goal this study was to reveal soil leaking fissures. Five typical types were selected area experiencing severe Guizhou Province, China. Dye tracer testing applied, combined digital image processing techniques. results indicated that both sides most form dyed ratio varied from 0.12 0.48 rock + profiles, 0.06 0.37 and between 0.02 0.16 interface. smallest terms their variation range patterns compared profiles. mainly occurs depth 0–20 cm. path affected by can pass clay layer poor permeability. part more than 50 main rapid downward area, which bottom