水土保持研究2025，Vol.32Issue(3)：8-17,10.DOI:10.13869/j.cnki.rswc.2025.03.032
模拟刚性植被盖度及配置方式对坡面流水动力参数及紊动特性的影响
Simulation of the influence of rigid vegetation coverage and configuration on overland flow hydrodynamics and turbulence characteristics
摘要
Abstract
[Objective]This study aims to reveal the effects of different vegetation configurations on the hydrody-namics and turbulence characteristics of overland flow.The findings will provide a scientific basis for understanding slope soil erosion mechanisms and optimizing vegetation resource configuration on slopes.[Methods]This study used an indoor flume scouring experiment to simulate various near-surface coverage levels of rigid vegetation(8.9%,4.5%,2.2%,1.1%,0.6%,0.3%),arbor-shrub configurations(shrub only,arbor-shrub combined,and arbor only),and spatial distributions(homogeneous,random,and aggregated)at six sets of different flow rates.It analyzed overland flow hydrodynamic parameters(water depth,flow velocity,flow pattern,and flow regime),the overall changes in flow resistance,and focused on the influence degree of different configuration factors on overland flow and their turbulence-promotion effects at the local scale.[Results](1)Vegetation coverage increased the average water depth of the slope by 1.3～2.3 times and reduced the average flow velocity by 16%～48%compared to the bare slope.The effect of different vegetation configurations on water depth increase and velocity reduction followed the order:dense>medium>sparse,shrub only>arbor-shrub combined>arbor only,random>homogeneous>aggregated,and the effect of the three configurations on overland flow was vegetation coverage>arbor-shrub configuration>spatial distribution.(2)The bulk drag coefficient of the vegetated slope showed a linear increasing trend with the increase of vegetation coverage(R2>0.90),and with the increase of flow rate,the trend was slower;the turbulence intensity showed a power function relationship with the increase of the comprehensive vegetation configuration parameter(R2>0.99).Under the same conditions of flow velocity,with the increase of coverage,the vegetated slope had the effect of generating wake to increase turbulence compared with the bare slope.Under the same conditions of hydraulic gradient,the level of turbulent kinetic energy of the vegetated slope compared with the bare slope appeared to first increase and then decrease.[Conclusion]Vegetation coverage has a greater impact on overland flow resistance and turbulence characteristics than arbor-shrub configuration or spatial distribution.As coverage increases,the balance between localized turbulence-promotion and macroscopic resistance-enhancement determines the ratio of turbulent kinetic energy to total kinetic energy in overland flow.关键词
坡面流/植被配置方式/模拟试验/水动力参数/紊动特性Key words
overland flow/vegetation configuration mode/simulation experiment/hydraulic parameters/turbulence characteristics分类
农业科技引用本文复制引用
贺元,张会兰,谷方正,王铃涵,李峰..模拟刚性植被盖度及配置方式对坡面流水动力参数及紊动特性的影响[J].水土保持研究,2025,32(3):8-17,10.基金项目
国家自然科学基金项目"植被结构影响下的坡面流挟沙力动力机制研究"(52279056) （52279056）
