AUTHOR=Deitrick Autumn R. , Hovendon Erin H. , Ralston David K. , Nepf Heidi 

TITLE=The influence of vegetation-generated turbulence on deposition in emergent canopies

JOURNAL=Frontiers in Marine Science

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1266241

DOI=10.3389/fmars.2023.1266241

ISSN=2296-7745

ABSTRACT=<p>Laboratory experiments measured sediment deposition and turbulent kinetic energy (TKE) in bare and vegetated channels. The model vegetation represented a mangrove pneumatophore canopy. Three solid volume fractions were considered (<inline-formula><mml:math display="inline" id="im1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>ϕ</mml:mi><mml:mo>=</mml:mo><mml:mo> </mml:mo></mml:mrow></mml:math></inline-formula> 0.01, 0.02, and 0.04). For the same channel-averaged velocity, the vegetated region had elevated near-bed TKE compared to the bare region. Net deposition in both regions was measured by adding a sediment slurry of 11-micron solid glass spheres to the flume and collecting the deposited sediment from the flume baseboards after a 4-hr experiment. The elevated near-bed TKE in the vegetated region resulted in lower deposition compared to the bare region. A model for deposition probability written in terms of near-bed TKE (TKE model) more accurately predicted the measured deposition than a model based on bed shear stress (<inline-formula><mml:math display="inline" id="im2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>τ</mml:mi><mml:mi>b</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> model). Application of the model to field conditions suggested that, by inhibiting deposition, vegetation-generated TKE facilitates the delivery of sediment farther into the mangrove forest than would be achieved without vegetation-generated TKE.</p>