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Title: Cohort Marsh Equilibrium Model (CMEM): History, Mathematics, and Implementation
Abstract Marsh accretion models predict the resiliency of coastal wetlands and their ability to store carbon in the face of accelerating sea level rise. Most existing marsh accretion models are derived from two parent models: the Marsh Equilibrium Model, which formalizes the biophysical relationships between sea level rise, dominant macrophyte growth, and elevation change; and the Cohort Theory Model, which formalizes how carbon mass pools belowground contribute to soil volume expansion over time. While there are several existing marsh accretion models, the application of these models by a broader base of researchers and practitioners is hindered because of (a) limited descriptions of how empirically derived ecological mechanism informed the development of these models, (b) limitations in the ability to apply models to geographies with variable tidal regimes, and (c) a lack of open‐source code to apply models. Here, we provide for the first time an explicit description of a mathematical version of the Cohort Theory Model and a numerical version of a combined model: the Cohort Marsh Equilibrium Model (CMEM) with an accompanying open‐sourceRpackage,rCMEM. We show that, through this “depth‐aware” model, we can capture how tidal variation impacts broad patterns of marsh accretion and carbon sequestration across the United States. The application of this model will likely be imperative in predicting the fate and state of coastal wetlands and the ecosystem services they provide in an era of rapid environmental change.  more » « less
Award ID(s):
1655622 1654853
PAR ID:
10505110
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
JGR Biogeosciences
Date Published:
Journal Name:
Journal of Geophysical Research: Biogeosciences
Volume:
129
Issue:
4
ISSN:
2169-8953
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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