Entrainment of sediment particles by very-large-scale motions

Acknowledgements The study has been supported by two EPSRC/UK grants, ‘High-resolution numerical and experimental studies of turbulence-induced sediment erosion and near-bed transport’ (EP/G056404/1) and ‘Bed friction in rough-bed free-surface flows: a theoretical framework, roughness regimes, and quantification’ (EP/K041088/1). The authors are grateful to three anonymous reviewers and the Editor for constructive criticisms and helpful suggestions that improved the presentation of the material in the paper.Peer reviewedPostprin