Lower threshold for marsh drowning suggests loss of microtidal marshes regardless of sediment supply

This is a Preprint and has not been peer reviewed.

Downloads

Download Preprint

Authors

Orencio Duran Vinent , Ellen Herbert, Matthew L. Kirwan

Abstract

Salt marshes are simultaneously among the most valuable and vulnerable ecosystems in the world. We use a simplified formulation for sediment transport across marshes to explain why marshes are most vulnerable to sea level rise (SLR) in microtidal environments. We find inorganic sediment decay length scales with tidal range so that inorganic deposition is very low in the interior of microtidal marshes regardless of the suspended sediment concentration at marsh edge. We also find that drowning of interior marshes eventually leads to a runaway marsh loss due to the approximate scale invariance of inorganic deposition. Thus, organic accretion rather than inorganic accretion is the key factor determining microtidal marsh survival. In fact, because in many locations the rate of SLR is close to or exceeds a theoretical maximum organic accretion rate for tidal salt marshes, our results suggest impending drowning of global microtidal marshes regardless of local sediment supply.

DOI

https://doi.org/10.31223/osf.io/cxvq6

Subjects

Earth Sciences, Environmental Sciences, Geomorphology, Natural Resources and Conservation, Physical Sciences and Mathematics

Keywords

Sea level rise, Marsh drowning, Micro tidal marshes, Wetland sedimentation

Dates

Published: 2019-10-10 15:58

Older Versions
License

GNU Lesser General Public License (LGPL) 2.1

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.