陈思 张升堂 张景洲 刘明

摘 要：为分析植被对水流阻力作用特征，给流域径流预测及坡面水力侵蚀等提供理论依据，从植被属性（柔性，刚性）、坡面流阻力、坡面流结构、数值模拟4个方面讨论植被对坡面流特性的影响，并探讨其影响规律及意义，对目前研究方法进行分析与展望。诸多学者通过理论分析、室外现场试验、水力模型试验等研究手段对水流阻力和水动力学特征等进行研究，结合目前研究现状，笔者认为存在以下问题：传统坡面流模拟试验是对刚性或柔性植被进行整体概化试验，而实际坡面植被性质复杂多样，不能全面论述其影响规律;阻力系数与雷诺数存在幂函数关系，但关于弗劳德数等其他流态相关参数对阻力系数影响的研究不多;对坡面流流态的界定存在争议，流态判别无统一定论。今后研究方向：①对更接近实际情况的植被进行研究;②产生新的适合于坡面流流态的推论和判断标准;③明确明渠水流阻力公式的适用条件及范围;④创新研究方法。

关键词：植被;坡面流;阻力系数;数值模拟;流态

中图分类号：TV131 文献标志码：A

doi：10.3969/j.issn.1000-1379.2021.05.009

Abstract： In order to analyze the characteristics of vegetation influenceto the water flow resistance and provide a theoretical basis for predicting runoff and hydraulic erosion in slope watersheds， this paper discussed the effects of vegetation on slope flow characteristics from the aspects of vegetation attributes （flexibility and rigidity）， slope flow resistance， slope flow structure and numerical simulation. Significance and the law of influence were also discussed. Moreover， the current research methods were analyzed and prospected. Scholars had studied flow resistance and hydrodynamic characteristics through theoretical analysis， field experiments， hydraulic model tests and other research methods. Combined with the current research status， the following problems are existed： the traditional slope flow simulation test is to conduct a generalized study on rigid or flexible vegetation， however， the nature of vegetation on slopes is complex and diverse， and its influence cannot be fully discussed; there is a power function relationship between the drag coefficient and the Reynolds number， but there are few studies on the influence of other flow-related parameters such as Froude number to the drag coefficient; the definition of slope flow pattern is controversial， leading to no unified conclusion on the determination of flow pattern. Therefore， the future research directions are that a） it should study the vegetation closer to the actual situation; b） a new inference and judgment standards suitable for the flow pattern of the slope surface needs to be generated; c） the applicable conditions and scope of the open channel flow resistance formula should be clarified and; d） breakthrough a new type of research method to study the influence mechanism of vegetation.

Key words： vegetation; slope water flow; resistance coefficient; numerical simulation; flow regime

1 引 言

坡面流是一種易受降雨、地形、土壤等因素影响的具有复杂流动边界的薄层水流，是导致水土流失的主要原因[1]。研究坡面流特性对水土保持及生态修复等具有重要意义。

植被在影响坡面流特性的诸多因素中不容忽视。在自然环境中，植被的存在对坡面流水动力研究及水利工程建设有……