【摘要】 [目的]探究坡面水沙运动过程中的尺度效应，阐明黄土高原丘陵沟壑区水沙运动尺度效应影响机制，进而为水沙传递机理研究及黄河流域水沙综合治理提供科学支撑。[方法]基于黄河子洲径流试验站4个径流场径流泥沙资料，通过对比分析次降雨事件下不同坡长产流产沙过程，揭示了坡面产流产沙的尺度传递效应。提出尺度传递效率概念，用来表征上下层级间水沙传递关系，进而探究了径流泥沙传递效率的影响因素。[结果](1)不同降雨类型特征因素对坡面产流产沙的影响不同，降雨历时主要影响坡面产流产沙能力，平均雨强主要影响坡面产流产沙起始时间；(2)次降雨事件下，不同坡长的径流传递是较为理想的平衡传递机制，且随坡长增加，径流的传递能力呈减小趋势。而在40～60 m坡长条件下，泥沙的传递表现为非平衡传递过程，随坡长增加，泥沙的传递能力呈先增大后减小的变化趋势；(3)不同尺度坡面水沙传递效率的影响因素不同，径流深、平均雨强及雨后表层土壤含水率是影响水沙尺度效率传递的主要因素。[结论]黄土丘陵沟壑区坡面产流产沙能力受降雨特性及坡长的影响，水沙沿程传递存在明显的折损或增益的尺度效应，水沙传递效率受雨强、径流及土壤湿度等多重因素的调控。更多还原

【Abstract】 [Objective] The aims of this study are to explore the scale effect in the process of runoff and sediment movement on the slope, to clarify the scale effect influence mechanism of runoff and sediment movement in the hilly and gully region of the Loess Plateau, so as to provide scientific support for the study of runoff and sediment transfer mechanism and the comprehensive management of runoff and sediment in the Yellow River Basin. [Methods] Based on the runoff and sediment data of four runoff fields in Zizhou runoff test station of the Yellow River, the scale transfer effect of runoff and sediment yield on slope was revealed by comparing and analyzing the runoff and sediment yield processes of different slope lengths under rainfall events. The concept of scale transfer efficiency was proposed to characterize the runoff and sediment transfer relationship between the upper and lower levels, and to further explore the influencing factors on runoff and sediment transfer efficiency. [Results](1) The characteristics of different rainfall types had different effects on the runoff and sediment yield on the slope. The rainfall duration mainly affected the runoff and sediment yield on the slope, and the average rainfall intensity mainly affected the starting time of runoff and sediment yield on the slope.(2) Under the event of rainfall, the runoff transfer of different slope lengths was an ideal equilibrium transfer mechanism, and with the increase of slope length, the transfer capacity of runoff showed a decreasing trend. Under the condition of 40～60 m slope length, the transfer of sediment was a non-equilibrium transfer process. With the increase of slope length, the transfer capacity of sediment increased first and then decreased.(3) The influencing factors on flow-sediment transfer efficiency on different scale slopes were different. Runoff depth, average rainfall intensity and surface soil moisture content after rain were the main factors affecting the transfer efficiency of flow-sediment scale. [Conclusion] The runoff and sediment yield capacity of the slope in the loess hilly and gully region is affected by rainfall characteristics and slope length. There is a significant scale effect of damage or gain in the transmission of runoff and sediment along the way. The efficiency of water and sediment transport is regulated by multiple factors such as rainfall intensity, runoff and soil moisture.更多还原