Sediment supply explains long‐term and large‐scale patterns in salt marsh lateral expansion and erosion

Ladd, C. J.T. , Duggan-Edwards, M. F., Bouma, T. J., Pagès, J. F. and Skov, M. W. (2019) Sediment supply explains long‐term and large‐scale patterns in salt marsh lateral expansion and erosion. Geophysical Research Letters, 46(20), pp. 11178-11187. (doi: 10.1029/2019GL083315)

213943.pdf - Published Version



Salt marshes often undergo rapid changes in lateral extent, the causes of which lack common explanation. We combine hydrological, sedimentological, and climatological data with analysis of historical maps and photographs to show that long‐term patterns of lateral marsh change can be explained by large‐scale variation in sediment supply and its wave‐driven transport. Over 150 years, northern marshes in Great Britain expanded while most southern marshes eroded. The cause for this pattern was a north to south reduction in sediment flux and fetch‐driven wave sediment resuspension and transport. Our study provides long‐term and large‐scale evidence that sediment supply is a critical regulator of lateral marsh dynamics. Current global declines in sediment flux to the coast are likely to diminish the resilience of salt marshes and other sedimentary ecosystems to sea level rise. Managing sediment supply is not common place but may be critical to mitigating coastal impacts from climate change.

Item Type:Articles
Additional Information:This research was supported by Coleg Cymraeg Cenedlaethol to C. J. T. L., by the Welsh Government and Higher Education Funding Council for Wales through Sêr Cymru National Research Network for Low Carbon, Energy and Environment to M. F. D.‐E., J. F. P., T. J. B., and M. W. S., by the Natural Environment Research Council (NERC) C‐SIDE Grant NE/R010846/1 to C. J. T. L. and M. W. S., and by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) BE‐SAFE Grant 850.13.011 and TTW AllRisk (P21.2 project B) for financial support in understanding the use of salt marshes for coastal defense to T. J. B.
Glasgow Author(s) Enlighten ID:Ladd, Dr Cai
Authors: Ladd, C. J.T., Duggan-Edwards, M. F., Bouma, T. J., Pagès, J. F., and Skov, M. W.
College/School:College of Science and Engineering > School of Geographical and Earth Sciences
Journal Name:Geophysical Research Letters
Publisher:American Geophysical Union
ISSN (Online):1944-8007
Published Online:09 October 2019
Copyright Holders:Copyright © 2019 American Geophysical Union
First Published:First published in Geophysical Research Letters 46(20: 11178-11187
Publisher Policy:Reproduced in accordance with the publisher copyright policy

University Staff: Request a correction | Enlighten Editors: Update this record