Assessment of flood dynamics in a mountain stream using high‐resolution river flow records
Assessment of flood dynamics in a mountain stream using high‐resolution river flow records
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DOI：
10.1002/hyp.14841
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发表时间：
2023-02
影响因子：
3.2
通讯作者：
Cong Xiao;K. Kawanisi;Mohamad Basel Al Sawaf;Xiaopan Zhu
中科院分区：
文献类型：
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作者：
Cong Xiao;K. Kawanisi;Mohamad Basel Al Sawaf;Xiaopan Zhu
了解径流水动力学对于预报山区河流的洪水现象具有重要意义。因此，基于不同径流技术(即额定曲线和河流声波层析成像(FAT))获得的长期径流观测，作者(1)对洪水现象进行了评估和探索，(2)讨论了大坝对洪水过程的影响，(3)揭示了河道弯道、沙洲和泛滥平原造成的回水效应。影响径流退缩的集水特性直接影响着过程线下降段的历时和坡度，而过程线上升段的行为则直接受降雨的影响。较高洪水事件的流量与降雨量之间的相关性较弱，表明降雨事件受到流域内大坝释放的水的强烈影响。此外，由于回水效应，水流速度和边界剪应力随流量的增加而变化的速率减小，潜在地减缓了侵蚀的速度。我们的发现对于山区河流的管理是相关的，特别是在易受回水影响的河弯地区。FAT方法有助于提高监测洪水和相关危险的短期波动的能力。
Understanding the streamflow hydrodynamics is important for forecasting flooding phenomena in mountainous rivers. Accordingly, based on long‐term runoff observations obtained using diverse runoff techniques (i.e., rating curves and fluvial acoustic tomography (FAT)), the authors (1) evaluated and explored flood phenomena, (2) discussed the effects of dams on flood hydrograph, (3) and revealed backwater effects caused by river channel bends, sand bars, and floodplains. The duration and slope of the falling limb of the hydrograph were directly influenced by the catchment characteristics that affected runoff recession, whereas the behaviour of the rising limb of the hydrograph was directly influenced by rainfall. A weaker correlation between discharge and rainfall in higher flood events indicates that rainfall events were strongly altered by water released from dams in the basin. Additionally, because of the backwater effects, the rate at which the flow velocity and boundary shear stress changed with the increasing discharge was reduced, potentially slowing the pace of erosion. Our findings are relevant for managing mountain rivers, particularly in river bend reaches prone to backwater effects. The FAT method could help increase the ability to monitor short‐term fluctuations in floods and associated hazards.