优先流问题研究及其科学意义

Preferential flow and its scientific significance

优先流是近年来针对土壤水运动所提出的术语,它是一种较为常见的土壤水分运动形式,与土壤入渗、地表及地下水质密切相关。开展优先流研究,是土壤水运动机制研究由均质走向非均质领域的标志。分析优先流的基本涵义及特征,阐述大孔隙流、环绕流、管流、漏斗流、指流、沟槽流、短路流、部分置换流、地下强径流、非饱和重力流、异质流、摆动流及低洼再蓄满等优先流类型及其表征现象,论述优先流研究的科学意义,并指出了优先流研究存在的问题及未来发展方向。

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.