山区河流阶梯-深潭研究应用进展

Research Progress and Application of Step-pool Systems in Mountain Streams

阶梯-深潭是大坡度山区河流常见而又十分重要的河床微地貌形态,河床常由一段陡坡和一段缓坡加上深潭相间连接而成,在河道纵向呈现一系列阶梯状。阶梯-深潭系统能有效耗散水流能量,控制河床侵蚀下切,并维持良好的河流生境和生态,因而是大坡度山区下切河流维持健康稳定的重要河床结构形态。20世纪80年代以来,国外对阶梯-深潭发育的环境条件、阶梯和深潭结构的形态特征和形成机理,以及河流地貌和生态效应等开展了大量研究,研究方法主要为野外调查、室内水槽实验及数学模型等。近年阶梯-深潭系统及相近的河床结构形态已经在山区河流治理上得到应用,并取得良好效果。本文为阶梯-深潭系统近30年研究进展和山区河流治理、修复应用情况的综合述评,并就未来研究方向提出建议。

Step-pool systems are a common geomorphologic configuration in high-gradient mountain streams（3%-5%） with alternating steps and pools having a stair-like appearance.Step-pool systems are very effective in dissipating flow energy and stabilizing riverbeds,and is an ecologically-sound riverbed pattern in mountain streams,thus it is an important streambed structure and micro-morphologic configuration for high-gradient mountain streams.Extensive research has been carried out on step-pool system since the 1980s through field investigation,flume experiment and mathematic model analysis.The research focused on step-pool development of environmental conditions,configuration feature,formation mechanism,and its hydraulic,geomorphologic and ecologic functions.Step-pool system and similar streambed structures have been applied to mountain stream restoration and stabilization in many countries in recent years,and have shown positive results.This paper synthesizes the recent literature and application cases of step pool,and discusses the possible research directions in the future.