The transitions from predominantly sandy to partly muddy conditions are denoted by black dots. The dashed part of the gray curves correspond to regions where, that is, predominantly sandy bed conditions, whereas the solid gray curve corresponds to regions where, that is, (partly) muddy bed conditions. Temporal evolution of sediment transport (colors) and final spatial distribution of erodibility f (gray) for low river discharge and.

The light blue solid line indicates the transition from a muddy bed during parts of the tidal cycle to a muddy bed during the entire tidal cycle. The light blue dashed line indicates the transition from a region with a predominantly sandy bed throughout the entire tidal cycle to a region with a muddy bed during parts of the tidal cycle. The plots show results after one year for (a) the erodibility f, (b) the distribution of along-channel surface SSC scaled against the maximum value, and (c) the maximum along-channel surface SSC. Sensitivity of model results to for the case of constant low river discharge. The gray dashed line indicates the transition between availability ( f < 1) and erosion-limited conditions ( f = 1). System transition from high to low discharge (left) and vice versa (right): the (a),(f) river discharge (b),(g) maximum value of the along-channel erodibility (c),(h) amount of sediment in the bottom pool (d),(i) transport over the seaward boundary and (e),(j) depth-integrated, tidally averaged concentration as a function of along-channel location. Temporal evolution of surface SSC and sediment mass for alternating high and low river discharge: (a) discharge time series, (b) tidally averaged surface SSC, and (c) sediment mass. The dashed gray curve in (c) corresponds to regions where, that is, predominantly sandy bed conditions, whereas the solid gray curve corresponds to regions where, that is, (partly) muddy bed conditions. (a) Final tidally averaged SSC, (b) temporal evolution of surface SSC, (c) temporal evolution of sediment transport, and (d) temporal evolution of sediment mass. Temporal evolution of SSC for constant low river discharge. The dashed gray curve in (c) corresponds to regions where, that is, predominantly sandy bed conditions. Temporal evolution of SSC for constant high river discharge: (a) final tidally averaged SSC, (b) temporal evolution of surface SSC, (c) temporal evolution of sediment transport, and (d) temporal evolution of sediment mass. Graphical representation of the functional relation for chosen to be. The variable names in green are the seaward and landward boundary conditions mentioned in the main text. Geometry of the tidal basin as adopted in the idealized model.

Importance of tidal pools in evolution