An Eco-Morphodynamic Modelling Approach to Estuarine Hydrodynamics & Wetlands in Response to Sea-Level Rise

Tidal inundation is the primary driver of intertidal wetland functioning and will be affected by sea- level rise (SLR). The morphology estuaries friction across surfaces influences tidal propagation; accordingly, sea-level not only increases frequency, but also alter other parameters, such as range. To investigate responses estuarine vegetation, primarily mangrove saltmarsh, to SLR an eco-morphodynamic modelling approach was developed that accounted for some feedbacks between changes substrate elevations. This model partially accounts adjustment in hydrodynamics, used examine potential effect on saltmarsh distribution a micro-tidal channelised infilled barrier estuary southeast Australia. combines depth-averaged hydrodynamic (Telemac2D) empirical elevation (WEM) were coupled dynamically allow eco-geomorphological feedbacks. integrated parameterised consider two scenarios, accretion scenarios within WEM. Time series observed water levels, flow velocity validate present-day sea level, whereas mapping verify predictions distribution. range varied along estuary, increasing response low high (by up 8%), responded non-linearly under SLR. Simulations indicated wetlands mostly withstand modest rates (+ 5mm yr -1 ) through sedimentation, submerge convert subtidal areas fast (> 10mm ). Projected are linked caused changing extents adjustments geomorphology sedimentation. Potential arising from morphological change at entrance channels obtained model. results this study demonstrate interconnections hydrodynamics wetlands, which need when estimating estuaries. Integrated models estuarine-wetland systems more precise they account dynamic wetlands. For example, alterations resulting effects these