摘要
为探明植被覆盖度对坡面水沙运动特性的作用,基于野外小区系列试验,采用苜蓿作为坡面植物,设置了范围在0~100%之间的6个不同植被覆盖度、6个不同的流量级(0.139~1.389L·s-1)条件下的共计36组坡面径流冲刷试验,对流速、含沙量、输沙率等方面进行了研究.试验结果表明:流速随着植被覆盖度的增大而减小,当植被覆盖度达到60%时,流速不再随植被覆盖度的变化而明显变化;含沙量随着植被覆盖度的增大迅速减小,相较于裸坡,当覆盖度大于20%时,含沙量即可减小60%,当覆盖度达到60%,含沙量可减少90%以上.植被覆盖度对坡面流速和输沙率的影响可分别用e-aVc和e-3aVc表示.本研究可为黄土高原坡面产沙能力估算提供一定的理论支撑.
In order to reveal the effect of the vegetation coverage on the characteristics of the overland flow and sediment transport,a series of clear water scour experiments in field located in the loess plateau of Qingyang,Gansu Province are carried out by planting the alfalfa on the slop to study the flow velocity,sediment concentration and sediment transport rate.The experiments are set under the conditions of 6 different vegetation coverage(0~100%)and 6 flow discharge(0.139~1.389 L·s-1),which are 36 groups in total.The results show that:the overland flow velocity decreases with the increase of vegetation coverage and no longer changes significantly when the vegetation coverage reaches 60%.The sediment concentration decreases with the increase of vegetation coverage.Compared to bare slope,the sediment concentration decreases by 60%when the coverage reaches 20%and decreases by more than 90%when the coverage is greater than 60%.The influence of vegetation coverage on overland flow velocity and sediment transport rate can be expressed as e-aVcand e-3 aVcrespectively.The results can provide some theoretical support for the estimation of slope sediment yield capacity in the loess plateau.
作者
孙一
刘晓燕
田勇
张旭
范小刚
崔其龙
SUN Yi;LIU Xiaoyan;TIAN Yong;ZHANG Xu;FAN Xiaogang;CUI Qilong(Yellow River Institute of Hydraulic Research YRCC,Zhengzhou 450003,China;Yellow River Conservancy Commission,Zhengzhou 450000,China;Shenzhen Water Planning&Designing Institute Co.,Ltd.,Shenzhen 518036,China;Xifeng Control and Supervision Bureau of Yellow River Soil and Water Conservation YRCC,Qingyang 745000,China;Inner Mongolia Hydrology Bureau,Huhhot 010020,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2020年第3期632-641,共10页
Journal of Basic Science and Engineering
基金
国家重点研发计划项目(2016YFC0402403)
国家自然科学基金项目(51809107)
关键词
坡面流
植被作用
植被覆盖度
流速
含沙量
输沙率
overland flow
vegetation effect
vegetation coverage
velocity
sediment concentration
sediment transport rate
