黄河下游河岸坡面产流产沙特征及其与汇流路径长度关系  

Runoff and Sediment Yielding Characteristics of Riparian Slopes along the Lower Reaches of the Yellow River and Their Relationships with Flowlength

作　　者：曹梓豪 赵清贺[1,2] ?左宪禹[4] 丁圣彦[1,2] 张祎帆 徐珊珊[1,2] 任嘉衍 CAO Zihao;ZHAO Qinghe;ZUO Xianyu;DING Shengyan;ZHANG Yifan;XU Shanshan;REN Jiayan(College of Environment and Planning,Henan University,Kaifeng,Henan 475004,China;Ministry of Education Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions,Henan University,Kaifeng,Henan 475004,China;Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China;Institute of Data andKnowledge Engineering,Henan University,Kaifeng,Henan 475004,China)

机构地区：[1]河南大学环境与规划学院,河南开封475004 [2]河南大学黄河中下游数字地理技术教育部重点实验室,河南开封475004 [3]北京师范大学地理科学学部,北京100875 [4]河南大学数据与知识工程研究所,河南开封475004

出　　处：《土壤学报》2018年第6期1389-1400,共12页Acta Pedologica Sinica

基　　金：国家自然科学基金项目(41301197);河南省高等学校重点科研项目(18A170004);河南省高校科技创新团队支持计划项目(16IRTSTHN012)资助~~

摘　　要：植被和地形是影响坡面侵蚀过程的重要因子,探讨两者交互作用下坡面产流产沙和汇流特征对深入理解坡面侵蚀过程和水土保持具有重要意义。采用模拟降雨试验,探讨不同降雨强度(54和90 mm·h^(-1))、坡度(5°、10°、15°、20°)和植被盖度(0%、15%、30%)下黄河下游河岸坡面的侵蚀产流、产沙特征,并基于水文连通性模型——汇流路径长度指数(Flowlength)探究植被和地形在土壤侵蚀过程中的作用以及汇流长度与产流产沙特征的关系。结果表明:54和90 mm·h^(-1)雨强下,不同植被盖度对径流流速均有减缓作用,而90 mm·h^(-1)雨强下30%盖度的减缓作用较为明显;径流总量和径流深随坡度和植被盖度增加而逐渐减少的变化基本一致,随雨强增加,受坡度影响逐渐增大。54 mm·h^(-1)雨强下,当坡度<15°时,侵蚀产沙量随坡度增加增幅较小;当坡度>15°后,侵蚀产沙量增幅较大。90mm·h^(-1)雨强下,当坡度<15°时,侵蚀产沙量随坡度增加而增加;当坡度>15°后,其随坡度增加而减少。相关分析表明,坡度对产沙量、产流量和径流深均具有显著影响,显著水平分别为P <0.001、P <0.01和P <0.05;植被盖度仅对平均流速影响显著(P <0.05)。但植被盖度对汇流路径长度影响极为显著(P <0.001),裸坡的汇流路径长度明显大于植被覆盖坡面;坡面产流产沙量随汇流路径长度的增加基本呈增加趋势。在坡度和植被盖度交互作用下,坡面产流所引发的土壤侵蚀效应受坡度影响较为明显,而在汇流过程所引发的土壤侵蚀效应中,植被的影响明显大于坡度。【Objective】Vegetation and topography are two important factors determining runoff and sediment yielding in slope soil erosion process. Studies reported in the past were mostly focused on effects of single control factors, e.g., slope gradient or vegetation cover, on runoff and sediment yielding, and few were found in the literature on coupling effects of vegetation and topography on runoff and sediment yielding and converging process. The Yellow River basin in China is one of the most severely eroded regions in the world, and the lower reaches of the River is world-famous for its silt-carrying load. Under the impact of a long history of human activities, its riparian zones have been suffering serious soil erosion. However, little has been reported quantitatively on soil erosion in the riparian zones of the River. What is more, restoration and preservation of the ecological functions of the riparian zones are closely related to the interactive effects of vegetation and topography on soil erosion and hydrological connectivity on the riparian slopes. 【Method】In this study, a field experiment simulating rainfall on riparian slopes along the lower reaches of the Yellow River to investigate runoff and sediment yielding characteristics as affected by rainfall intensity(54 and 90 mm h-1), slope gradient(5°, 10°, 15°, and 20°), and vegetation coverage(0%, 15%, and 30%), as well as effects of slope gradient and vegetation coverage on soil erosion and relationships of runoff and sediment yielding characteristics with flowlength with the aid of a hydrological connectivity model. 【Result】Results show that vegetation cover, regardless coverage, helped reduce runoff velocity under rainfall, no matter how heavy, either 54 or 90 mm h-1 in rainfall intensity, and the effect was the most significant on a slope 30% in vegetation coverage under artificial rainfall, 90 mm h-1 in intensity. Runoff on slopes varied in volume and depth consistently, gradually declining with rising slope gradient and vegetation coverage, a

关 键 词：河岸坡面 产流产沙 汇流路径长度 水文连通性 黄河下游 

分 类 号：S157.1[农业科学—土壤学]