How important is mud transport on large scale estuarine and deltaic morphodynamics?

Sediment transport provides a critical bridge between hydrodynamics and morphodynamics. Sediment transport behaviour has obvious impacts on morphodynamic development. Long-term morphodynamic modelling enables examination of large scale morphological patterns, such as channel-shoal patterns in estuaries and deltaic channel structures. Non-cohesive sand is mostly used as the material in shaping morphology. However, most of estuaries and deltas in nature are partly or fully dominated by cohesive sediment or mud. There are researches on sand-mud interactions and their implications on total sediment transport (van Ledden, 2003). It is increasingly aware that adding mud to the system can make a big differences on the large scale morphodynamic development behaviour (Edmond and Slinger, 2009; Gelynese et al., 2010; Caldwel and Edmond, 2014). However mud transport is notoriously difficult to be defined properly in the model given the combined sensitivity to a few fundamental parameters (Partheniades, 1965; Mehta, 2014). It is thus not clearly known how mud have controls on development of large scale morphodynamics and the sensitivity to the mud property.