Abstract Vegetation plays a significant role in river ecosystem, which has a great influence on hydraulic structures and sediment transport. Understanding the vertical distribution of suspended sediment concentration (SSC) in canopy flow is helpful to study the process of riverbed erosion and deposition in vegetated channels. Aiming at the sediment-laden flow in open channel covered with submerged vegetation, this study divides the water depth into two layers along the vertical direction with the vegetation height as the boundary and then proposes a new SSC distribution model based on gravitational theory to estimate the vertical distribution of relative SSC in the free water layer and vegetation layer respectively. In the meanwhile, a new formula is also proposed to evaluate the Reynolds shear stress below the submerged vegetation height, which has been successfully applied in the derivation of the new SSC distribution model. The validation results of the simplified velocity model, the new Reynolds shear stress formula and the new SSC model compare well with the collected experimental data series. On top of that, it is found that the uniformity of SSC distribution profile progressively decreases with the increasing sediment particles diameters. Besides, according to the validation results and discussion, it is believed that the controversy point about gravitational theory would not have obvious influence on the estimation of SSC distribution so that the gravitational theory can be adopted to investigate suspended sediment transport in vegetation flow. That would be benefit for river ecological restoration and better management.

中文翻译：

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基于引力理论估算淹没植被流中悬浮泥沙浓度分布

摘要 植被在河流生态系统中扮演着重要角色，对水力结构和泥沙输移有很大影响。了解冠层流中悬浮泥沙浓度（SSC）的垂直分布有助于研究植被河道中河床侵蚀和沉积的过程。本研究针对淹没植被覆盖的明渠中的载沙流，将水深沿垂直方向以植被高度为边界分为两层，然后提出了一种基于引力理论的新的SSC分布模型来估计相对SSC分别在自由水层和植被层的垂直分布。同时，还提出了一种新的公式来计算淹没植被高度以下的雷诺剪应力，已成功应用于推导新的 SSC 分配模型。简化速度模型、新雷诺剪应力公式和新 SSC 模型的验证结果与收集到的实验数据系列的结果很好地比较。最重要的是，发现SSC分布剖面的均匀性随着沉积物颗粒直径的增加而逐渐降低。此外，根据验证结果和讨论，认为引力理论的争议点不会对SSC分布的估计产生明显影响，因此可以采用引力理论研究植被流中的悬浮泥沙输运。这将有利于河流生态恢复和更好的管理。