摘要
[目的]揭示紫色土坡面细沟形态特征及其对产流产沙的影响,阐明紫色土区影响细沟产流产沙的主控因素,进而为紫色土区水土流失治理提供参考依据。[方法]以紫色土坡耕地为研究对象,设计3个流量(6,8,10 L/min)和5个坡长(1,2,3,4,5 m),利用放水冲刷试验定量分析细沟形态和产流产沙变化特征,探讨细沟形态变化对产流产沙特征的影响。[结果]随流量增加,沟宽和沟深均呈增大趋势,宽深比则呈减小趋势;随坡长增加,沟宽与宽深比呈先减小后增大的趋势,沟深变化规律则相反,且细沟形态在坡长3~4 m存在突变。流量与产流率、产沙率和细沟侵蚀速率呈正相关关系,坡长与产沙率呈正相关关系,而与产流率和细沟侵蚀速率呈负相关关系,其中产流率主要受流量的影响,而产沙率和细沟侵蚀速率受流量和坡长交互作用的影响较大。相关性分析表明,相比于产流(r=0.54,p<0.05),细沟形态与产沙关系更为密切(r>0.67,p<0.01)。通过多元逐步回归分析发现,沟宽是影响细沟侵蚀速率的关键因素(p<0.05),沟深是影响产沙率、累积产沙量的关键因素(p<0.01)。[结论]沟宽与沟深可用于预测紫色土坡面侵蚀程度,其中沟深是表征侵蚀产沙的最佳指标,未来细沟侵蚀防治措施重点应在控制沟深发育方面。
[Objective]The aim of this study is to explore the influence of rill morphology characteristics to runoff and sediment yield on purple soil slope as well as the main controlling factors affecting runoff and sediment yield in rill,and then to provide a reference for soil erosion control in purple soil area.[Methods]Purple sloping farmland was taken as the research object.A series of the scouring-erosion experiments were conducted under the different slope length(1,2,3,4 and 5 m)and flow discharge(6,8 and 10 L/min).The scouring-erosion experiments were used to quantitatively analyze the variation of rill morphology and the characteristics of runoff and sediment yield,and the influence of rill morphology variation on the characteristics of runoff and sediment yield was discussed.[Results]With the increase of flow discharge,the rill width and rill depth increased,and the width-depth ratio decreased.With the increasing of slope length,the rill width and width-depth ratio showed the decrease-increase trend,while the rill depth showed the contrary tendency,and the rill morphology had a sudden change in the slope length of 3~4 m.Flow discharge was positively correlated with runoff yield rate,sediment yield rate and rill erosion rate.Slope length was positively correlated with sediment yield rate,but negatively correlated with runoff yield rate and rill erosion rate.Runoff yield rate was mainly affected by flow discharge,sediment yield rate and rill erosion rate were mainly affected by the interaction of flow discharge and slope length.Rill morphology had a weak relationship with the runoff(r=0.54,p<0.05),and was closely related to the sediment yield(r>0.67,p<0.01).Through multiple stepwise regression analysis,it was found that rill width was the key factor affecting the rill erosion rate(p<0.05),and rill depth was the key factor affecting sediment yield rate and cumulative sediment yield(p<0.01).[Conclusion]Rill width and rill depth could be used to predict the erosion degree of purple soil slope,and rill depth could be
作者
苟俊菲
甘凤玲
刘春红
GOU Junfei;GAN Fengling;LIU Chunhong(Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area,Chongqing Normal University,Chongqing 401331,China;Chongqing Field Observation and Research Station of Surface Ecological Process in the Three Gorges Reservoir Area,Chongqing 401331,China)
出处
《水土保持研究》
CSCD
北大核心
2023年第5期61-68,75,共9页
Research of Soil and Water Conservation
基金
国家青年科学基金项目(42107355)
重庆市基础研究与前沿探索项目(cstc2018jcyjAX0489)
重庆市教委科技项目(KJQN201800531,KJQN202100518)
重庆市科委面上项目(CSTB2022NSCQ-MSX1053)。
关键词
细沟形态
产流率
产沙率
细沟侵蚀速率
流量
坡长
紫色土坡面
rill morphology
runoff yield rate
sediment yield rate
rill erosion rate
flow discharge
slope length
purple soil slope
