Document Type
Article
Department/Program
Virginia Institute of Marine Science
Publication Date
9-28-2020
Journal
Geophysical Research Letters
Volume
47
Issue
18
First Page
e2020GL089121
Abstract
Coastal marshes and their valuable ecosystem services are feared to be lost by sea level rise, yet the mechanisms of marsh degradation into ponds and potential recovery are poorly understood. We quantified and analyzed elevations of marsh surfaces and pond bottoms along a marsh loss gradient (Blackwater River, Maryland, USA). Our analyses show that ponds deepen with increasing tidal channel width connecting the ponds to the river, indicating a new feedback mechanism where channels lead to enhanced tidal export of pond bottom material. Pond elevations also decrease with increasing pond size, consistent with previous work identifying a positive feedback between wind wave erosion and pond size. These two positive feedbacks, combined with bimodal elevation distributions and sharp topographic boundaries between interior ponds and the marsh platform, indicate alternative elevation states and imply that marsh loss by pond formation is nearly irreversible once pond deepening exceeds a critical level.
DOI
doi: 10.1029/2020GL089121
Keywords
Coastal marshes, pond expansion, marsh degredation
Recommended Citation
Schepers, Lennert; Brennand, Patrick; Kirwan, Matthew L.; Guntenspergen, Glenn; and Temmerman, Stijn, Coastal Marsh Degradation Into Ponds Induces Irreversible Elevation Loss Relative to Sea Level in a Microtidal System (2020). Geophysical Research Letters, 47(18), e2020GL089121.
doi: 10.1029/2020GL089121
Supplementary material
