Key Laboratory of Soil and Water Conversation & Desertification Combating of Ministry of Education; College of Soil and Water Conservation, Beijing Forestry University: 100083, Beijing, China
Abstract:Preferential flow, a term about water movement in soil, was brought forward in recent years, which indicates an ordinary transport phenomenon of rapid and non-equilibrium of water and solutes in most of soil and also has a very close relationship with the ground, surface waters and runoff processes. A start of preferential research symbolizes that mechanism of soil water movement is from homogeneous to heterogeneous field. Basic meanings and characteristics of preferential flow are systematically analyzed, and preferential flow's types and their characteristic phenomena are particularly expounded such as macropore flow, bypass flow, pipe flow, funnel flow, finger flow, channel flow, short circuiting flow, partial displacement flow, subsurface storm flow, gravity-driven unstable flow, heterogeneity-driven flow, oscillatory flow and depression-focused recharge, ect, and meanwhile, scientific significances, problems and developing directions in future are discussed.