THE DYNAMICS OF INTERTISDAL MUDFLATS AND SALTMARSHES WITHIN ESTUARIES

Ian Townend, Kate Rossington, Michiel Knaapen, Stephen Richardson

Abstract


Whilst there has been extensive work on the study of the morphological response of estuaries, due to the transport of sediment under the forcing of waves and tides, and independent studies on the dynamics of saltmarsh, only recently have attempts been made to look at the interaction of the two. This paper furthers this endeavor by adding a simple saltmarsh model into the aggregated scale model of long-term morphology known as ASMITA. The results show the strong interaction between sediment availability within the estuary and marsh depth and, hence, the species that can be sustained. Under low rates of sediment loading the biology is the controlling influence, whereas under higher rates, typical of many UK estuaries, the sediment loading tends to be dominant. The importance of both the rate of sea level rise and the nodal tidal cycle are also explored.

Keywords


estuary; saltmarsh; geomorphology; dynamic equilibrium; sea level rise; lunar nodal tidal cycle

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