Most studies on sediment transport and bedforms migration consider unlimited sediment supply conditions. However, areas where the sediment supply is limited are common in coastal and fluvial environments. The present paper, based on physical modelling in a flume and on a re-analysis of field data obtained in the Eastern English Channel by Ferret (Morphodynamique des dunes sous-marines en contexte de plate-forme mégatidale (manche orientale). approche multi-échelles spatio-temporelles, 2011), considers the effects of sediment supply limitation on bedload transport and bedforms migration velocity. The bedload transport is found to be proportional to the fraction of the bed covered by sediments for a bed exhibiting bedforms. The migration velocity of bedforms depends on the dominant mode of sediment transport. A new formulation showing a good agreement with experimental tests and observations in the field is proposed for the dimensionless migration velocity of these bedforms when sediment transport is dominated by bedload, under unlimited sediment supply conditions. For limited sediment supply conditions and sediment transport dominated by bedload, an adaptation of the formulation is suggested from flume data sets, based on the fraction of the bed covered by sediment.

中文翻译：

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砂供应限制下的基床运输和床形迁移

关于泥沙运移和床形迁移的大多数研究都考虑到无限量的泥沙供应条件。但是，沉积物供应有限的地区在沿海和河流环境中很常见。本文基于水槽中的物理建模，并重新分析了雪貂在东英吉利海峡获得的野外数据（Morphodynamique des dunes sous-marines en contexte de plate-formemégatidale（manche Orientale））。 échellesspatio-temporelles，2011），考虑了泥沙供应限制对床荷运输和床形运移速度的影响。对于具有床状的床，发现床床运输与床被沉积物覆盖的床的比例成比例。床形的迁移速度取决于沉积物运移的主要方式。提出了一种新的配方，该配方与实地的实验测试和观察结果吻合良好，提出了在无限量的泥沙供应条件下，当泥沙运移以床荷为主导时，这些床形的无量纲迁移速度的方法。对于有限的沉积物供应条件和以床载量为主的沉积物输送，建议根据水道数据集根据沉积物覆盖的床层比例对配方进行调整。