Skip to main content

Research Repository

Advanced Search

Flexural rigidity and shoot reconfiguration determine wake length behind saltmarsh vegetation patches

Marjoribanks, T.I.; Lague, D.; Hardy, R.J.; Boothroyd, R.J.; Leroux, J.; Mony, C.; Puijalon, S.

Flexural rigidity and shoot reconfiguration determine wake length behind saltmarsh vegetation patches Thumbnail


Authors

T.I. Marjoribanks

D. Lague

R.J. Boothroyd

J. Leroux

C. Mony

S. Puijalon



Abstract

Vegetation patches play an important role in controlling sediment deposition in shallow aquatic environments such as coastal saltmarshes and fluvial systems. However, predicting deposition around vegetation patches is difficult due to the complexity of patch morphology and their dynamic interaction with the flow. Here we incorporate a biomechanical model, parameterized using field data, within a 3D computational fluid dynamics (CFD) model which allows prediction of individual shoot reconfiguration within patches due to flow forcing. The model predicts velocity attenuation and bed shear stresses within the wake of the patch which agree spatially with accretion patterns measured in the field using terrestrial LiDAR. The model is applied to sparse patches of Suaeda maritima, located in saltmarshes of coastal habitats, to explore the role of (I) shoot distribution, (II) patch geometry, (III) shoot flexural rigidity and (IV) bulk flow velocity in determining the length of the predicted wake region. We demonstrate that for Suaeda maritima, with intermediate rigidity, the vertical shear layer over the vegetation controls the length of the predicted wake region. Consequently, reconfiguration due to flexural rigidity strongly impacts on wake length, confounding the relationship between patch height and wake length. A simplified model for predicting wake length based on shoot reconfiguration is applied to the simulation data and shows good agreement. The results demonstrate that the observed wake characteristics can be well‐explained by intraspecific variability in flexural rigidity, thus demonstrating the importance of biomechanical traits in determining flow‐vegetation‐sediment interactions.

Citation

Marjoribanks, T., Lague, D., Hardy, R., Boothroyd, R., Leroux, J., Mony, C., & Puijalon, S. (2019). Flexural rigidity and shoot reconfiguration determine wake length behind saltmarsh vegetation patches. Journal of Geophysical Research: Earth Surface, 124(8), 2176-2196. https://doi.org/10.1029/2019jf005012

Journal Article Type Article
Acceptance Date Aug 2, 2019
Online Publication Date Aug 17, 2019
Publication Date Aug 31, 2019
Deposit Date Aug 16, 2019
Publicly Available Date Aug 22, 2019
Journal Journal of geophysical research. Earth surface.
Print ISSN 2169-9011
Electronic ISSN 2169-9011
Publisher American Geophysical Union
Peer Reviewed Peer Reviewed
Volume 124
Issue 8
Pages 2176-2196
DOI https://doi.org/10.1029/2019jf005012

Files

Published Journal Article (Advance online version) (2 Mb)
PDF

Publisher Licence URL
http://creativecommons.org/licenses/by/4.0/

Copyright Statement
Advance online version © 2019. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.








You might also like



Downloadable Citations