Data for: The pace of global river meandering influenced by fluvial sediment supply

Meandering rivers move gradually across the floodplains, and this river movement presents socioeconomic risks along river corridors and regulates terrestrial biogeochemical cycles. Experimental and field studies suggest that fluvial sediment supply can exert a primary control on lateral migration rates of rivers. However, we lack an understanding of the relative importance of environmental boundary conditions, such as floodplain vegetation and sediment supply, in setting the pace of river meandering across different environmental settings. Here, we combine the analysis of satellite imagery and global-in-scale sediment and water discharge models to evaluate the controls on lateral migration rates of 139 meandering rivers that span a wide range in size, climate, and bank vegetation. We show that migration rates normalized by the channel width monotonically increase with the volumetric sediment flux normalized by the characteristic size of the river. This relation is consistent across rivers in vegetated and unvegetated catchments, indicating that enhanced lateral migration rates in unvegetated basins is likely not only facilitated by lower bank mechanical strength, but also by higher normalized sediment supply in ephemeral rivers. Using three case examples, we also demonstrate that width-normalized meander migration rates respond to spatial gradients in sediment supply caused by river impoundments, highlighting the prominent role of sediment supply in setting the pace of meander migration. Our results suggest that sediment-supply variations caused by climate, land-cover and land-use changes can lead to predictable changes in meandering river evolution and ultimately drive architectural changes in sedimentary stratigraphy.

曲流河（meandering river）会在漫滩（floodplain）上缓慢迁移，这种河道迁移行为不仅会在沿河廊道带来社会经济风险，同时也会调控陆地生物地球化学循环。实验与野外研究表明，河流沉积物供给（fluvial sediment supply）是控制河道侧向迁移速率的核心影响因素。然而，针对不同环境背景下曲流河迁移速率的调控机制，目前学界尚未明确漫滩植被、沉积物供给等环境边界条件的相对重要性。本研究结合卫星影像分析与全球尺度的沉积物、水流量模型，针对139条涵盖不同河道规模、气候条件与岸带植被类型的曲流河，评估其侧向迁移速率的控制因素。研究结果表明，以河道宽度归一化的迁移速率，会随以河道特征尺度归一化的沉积物体积通量呈单调递增趋势。该规律在有植被覆盖与无植被覆盖的两类流域中均成立，这意味着无植被流域内侧向迁移速率的提升，不仅可能源于岸带机械强度更低，同时也与暂时性河流（ephemeral river）中更高的归一化沉积物供给密切相关。本研究还通过三个案例证实，以河道宽度归一化的曲流迁移速率会响应河道筑坝引发的沉积物供给空间梯度，进一步凸显了沉积物供给在调控曲流迁移速率中的核心作用。本研究结果表明，由气候变化、土地覆盖与土地利用变化引发的沉积物供给变化，会导致曲流河演化出现可预测的改变，并最终推动沉积地层的结构演化。

搜集汇总

背景与挑战

背景概述

该数据集是一个全球尺度的河流蜿蜒迁移研究数据集，结合卫星图像和全球沉积物与水流模型，分析了139条河流的侧向迁移率，重点探讨了沉积物供应对河流蜿蜒速度的影响。数据集包含三个部分：Dammed_Rivers（3条河流的水坝影响数据）、Single_Rivers（55条河流的原始数据）和Tabular_Data（汇总139条河流的表格数据），总大小约34.6 MB，适用于河流地貌学、环境科学和遥感应用研究。