Abstract In this study, the mechanism of channel-floodplain seasonal connectivity along the Amazon River is analyzed over a full hydrological year through the use of satellite radar altimetry data (Jason-2). This is done via a novel observation-based approach which employs the concurrent measurement of water levels (WLs) over river and floodplain, analyzing seasonal changes in water surface height differences between the two water bodies. Hydrological connectivity thresholds at different stages during the rising phase were identified, and then validated using field data and remote sensing-driven surface suspended sediment maps. Successful decoupling of the two indiscrete flooding processes during the rising phase: channelized and overbank dispersion processes, is one of the major outcomes of this study. Different roles of the connectivity processes on floodplain hydrogeomorphology are highlighted – that channelized flows determine inundation frequency, residence time and development of positive topographic features in the floodplain, while overbank flows contribute a good part of the seasonal water storage and sediment budget in the floodplain, and tends to smooth positive topography built by channelized flows. The zones of overbank flooding, however, are rather localized due to the well-developed natural levee complex and stable channel-dominated floodplain along the river bank. Lastly, the presented approach is straightforward and solely based on publicly available operational data, making it easily adaptable by non-remote sensing experts. Thus, along with the emergence of new radar altimetry platforms, such as ICESat-2 or Jason-3 that could measure WL of smaller lakes, the proposed approach offers the potential to contribute to research on channel-floodplain systems in other rivers at a global scale.

中文翻译：

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使用卫星测高表征河道-漫滩连通性：机制、水文地貌控制和沉积物收支

摘要 在这项研究中，通过使用卫星雷达测高数据 (Jason-2)，分析了整个水文年沿亚马逊河河道-泛滥平原季节性连通的机制。这是通过一种新颖的基于观测的方法完成的，该方法采用同时测量河流和洪泛区的水位 (WL)，分析两个水体之间水面高度差异的季节性变化。确定上升阶段不同阶段的水文连通性阈值，然后使用现场数据和遥感驱动的表层悬浮沉积物图进行验证。本研究的主要成果之一是在上升阶段成功地解耦了两个不离散的洪水过程：渠道化和堤岸扩散过程。强调了连通性过程对漫滩水文地貌的不同作用——渠道化流量决定了漫滩中的淹没频率、停留时间和积极地形特征的发展，而河岸流贡献了漫滩季节性蓄水和沉积物收支的很大一部分，并趋于平滑由通道化流构建的正地形。然而，由于沿河岸发育良好的天然堤坝和稳定的以河道为主的漫滩，泛滥泛滥的区域相当局部化。最后，所提出的方法简单明了，完全基于公开可用的操作数据，使其易于被非遥感专家采用。因此，随着新型雷达测高平台的出现，