黄土坡面侵蚀过程与侵蚀-沉积空间分布特征  

Erosion process and spatial distribution characteristics of erosion-deposition on the loess slope

作　　者：徐振剑[1] 权鑫 史红伟 和继军[1] 蔡强国[3] 孙莉英[3] XU Zhenjian;QUAN Xin;SHI Hongwei;HE Jijun;CAI Qiangguo;SUN Liying(State Key Laboratory of Urban Environmental Processes and Numerical Simulation,Capital Normal University,Resources Environment and GIS Key Lab of Beijing,Beijing 100048,China;Ministry of Water Resources Construction Management and Quality and Safety Center,Water Conservancy Engineering Management Department,Beijing 100038,China;Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100101,China)

机构地区：[1]首都师范大学城市环境过程和数字模拟国家重点试验室培育基地,北京资源环境与GIS重点试验室,北京100048 [2]水利部建设管理与质量安全中心,水利工程管理处,北京100038 [3]中国科学院地理科学与资源研究所,中国科学院大学资源与环境学院,北京100101

出　　处：《陕西师范大学学报（自然科学版）》2021年第6期98-105,共8页Journal of Shaanxi Normal University：Natural Science Edition

基　　金：国家自然科学基金(41771314,41401302)。

摘　　要：采用室内人工模拟降雨试验及三维激光扫描技术,研究不同坡度和雨强作用下坡面土壤侵蚀-沉积的空间分布与变化规律,并结合传统的水沙观测分析黄土坡面侵蚀过程。结果表明:雨强是影响黄土坡面初始产流的主要因素,坡度可以通过改变土壤入渗率、径流动能以及承雨量对产流产生影响。总径流量随雨强的增加而显著增加,随坡度的增加呈先增加后减少趋势。在1.0 mm/min雨强时,总侵蚀量随坡度增加而增加;在1.5 mm/min雨强时,随坡度的增加呈先增大后减少的趋势,与径流量趋势一致。各坡度下,坡面产流率表现为降雨初期增速较快、后期增速较缓的变化趋势;侵蚀率随着产流率的增加表现为先增大后减小的变化趋势,且坡度增加会显著缩短侵蚀率达到峰值的时间,其中1.5 mm/min雨强时表现尤为明显,大雨强和大坡度更容易使径流对泥沙的剥离-搬运-沉积过程达到平衡状态。不同雨强和坡度下黄土侵蚀-沉积的空间分布存在一定差异,总体上表现为大部分坡度下坡面侵蚀从坡顶到坡脚逐渐减弱,且侵蚀-沉积的强弱分区较为明显,其中陡坡度时土壤侵蚀更明显,特别是在坡面的中上部。In this study,indoor simulated rainfall test and 3D laser scanning technology were used to study the spatial distribution and change rule of soil erosion-deposition under different slopes and rainfall intensity and the erosion process of loess slope was analyzed by combining traditional water and sediment observation.The results showed that the rainfall intensity is the main factor affecting the initial runoff yield on loess slope and the gradient can affect the runoff yield by changing soil infiltration rate,runoff kinetic energy and received rainfall.The total runoff increased significantly with the increase of rainfall intensity and it increased first and then decreased with the increase of gradient.When the rainfall intensity was 1.0 mm/min,the total erosion increased with the increase of gradient.When the rainfall intensity was 1.5 mm/min,the total erasion first increased and then decreased with the increase of gradient,which was consistent with the trend of runoff.For each slope,the runoff yield showed a trend of faster growth in the early stage of rainfall and a slower growth in the later stage.Erosion rate increased first and then decreased with the increase of runoff yield rate,and the increase of gradient significantly reduced the time for erosion rate to reach its peak especially when the rainfall intensity is 1.5 mm/min.Heavy rain intensity and large gradient made it easier to reach an equilibrium state in the process of sediment detachment,transport and deposition.The spatial distribution of erosion-deposition of loess varied with different rainfall intensities and gradients.Generally speaking,the erosion gradually weakened from the top to the bottom of the slope and there is a strong and weak zone of erosion-deposition among which the soil erosion is more obvious when the gradient is steep,especially for the middle and upper part of the slope.

关 键 词：人工模拟降雨 坡面侵蚀 三维激光扫描 空间分布 

分 类 号：S157.1[农业科学—土壤学]