Natural sediment in aquatic environments comprise non-cohesive sands, physically-cohesive muds and biologically-active cohesive extracellular polymeric substances; these mixtures account >70% of sediments globally. Cohesive sediments strongly influence interplay between hydrodynamics and morphodynamics through a range of mechanisms; altering fluid properties, damping wave spectra, reducing turbulence, to zoning chemical species. Temporally, such interactions alter tidal currents and internal waves through to gravity-driven currents and tsunami flows, by alterations to sedimentary processes such as forced aggregation, turbulence induced flocculation, and hindered deposition. Moreover, ranges of complex bio-mediated processes and symbiotic relationships exist between biota and sediment substrates, which further evolve cohesive sediment properties through numerous (poorly) understood mechanisms.

This session welcomes presentations on: recent laboratory, field, theoretical and numerical studies addressing roles cohesive sediments play in detailed relationships between hydrodynamics and morphodynamics through to impacts these complex interactions have on character and nature of process to product relations recorded in sedimentary architecture.