This study focuses on typical 5th-order sub-basins within the Yellow River Basin, integrating climatic, underlying surface, and streamflow data to examine how river network structure affects the hierarchical characteristics of streamflow. Based on Horton’s laws, this study reveals that the streamflow ratio (R_Q) exhibits statistically significant self-similarity within stream levels 1–3 in the 5th-order sub-basins, consistent with the self-similar ranges of structural parameters such as bifurcation ratio (R_B), length ratio (R_L), and area ratio (R_A). Among these, R_A serves as a key reference template for streamflow hierarchy, with 75% of the sub-basins showing an  ratio between 0.95 and 1.05. Additionally, 65% of the sub-basins have  values below 1, indicating that under semi-arid climatic conditions, the growth of streamflow with stream order is generally slower than the areal expansion rate of contributing sub-basins. Further analysis demonstrates significant positive correlations (R > 0.5, p < 0.05) between  and precipitation, aridity index, and soil moisture, suggesting that sub-basins with higher rainfall and more substantial groundwater recharge exhibit a more pronounced increase in streamflow with stream order and drainage area. These findings highlight the synergistic influence of river network structure and basin characteristics on streamflow hierarchy, offering insights for water resource management in basins with diverse river network morphologies.

基于黄河流域典型5级子流域水系, 结合流域气候下垫面信息与径流数据, 识别水系结构对河道径流分级特征的影响。基于霍顿水系定律的分析结果表明, 黄河5级子流域不同级别河流的河道径流比(R_Q)在1~3 级范围内呈现较为显著的自相似特性, 与水系结构参数分支比(R_B)、河长比(R_L)和面积比(R_A)的自相似范围一致。其中, R_A是河道径流分级特征的重要参照模板, 有75%的子流域 1~5级R_Q平均值与R_A平均值的比值()在0.95~1.05范围内。同时, 65%的子流域 <1, 说明在半干旱气候条件下, 大部分子流域河道径流随河流级别的增速小于所对应各级子流域面积的增速。水系的 与流域降水量、干旱指数和土壤含水量显著正相关(R>0.5, p<0.05), 意味着降水量较大且地下水补给相对充沛的子流域的河道径流量随河流级别与汇水面积的增加更为显著。研究结果凸显水系结构与流域特征要素对河道径流分级特征的协同影响, 可为干旱气候区流域水资源管理提供科学依据。