THEME 3: Bio-sedimentology: The investigation of the biological mediation of sediment dynamics and its role in ecosystem engineering.
The SERG group has an established track record of examining the interaction between the biology and physical dynamics of soft sediment systems. This area of work arose from the understanding that almost all natural sediments support varying populations of organisms which significantly alter the response of sediment to physical forcing. The impact of this biogenic mediation of sediment dynamics was rarely considered by sedimentologists and almost always missing from dynamic models of sediment erosion and transport. This is understandable because predictions highly variable and context-dependant (season, sites, condition) biological effects are extremely problematic but the role of these effects has to be recognised to fully understand system behaviour.
Several mechanisms have been shown to produce this stabilisation, including the building of biogenic structures and the production of extracellular polymeric substances (EPS). The possibility that the use of biochemical parameters can improve the modelling of sediment erodibility is being investigated. This has significant economic importance for the environmental assessment of coastal engineering projects. An additional and complimentary part of this research involves the development of techniques to measure the stability of sediments in situ. See our methods for details on these techniques.