The lateral extent and vertical stability of salt marshes experiencing rising sea levels depend on interacting drivers and feedbacks with potential for nonlinear behaviors. A two-dimensional transect model was developed to examine changes in marsh and upland forest lateral extent and to explore controls on marsh inland transgression. Model behavior demonstrates limited and abrupt forest retreat with long-term upland boundary migration rates controlled by slope, sea-level rise (SLR), high water events, and biotic-abiotic interactions. For low to moderate upland slopes the landward marsh edge is controlled by the interaction of these inundation events and forest recovery resulting in punctuated transgressive events. As SLR rates increase, the importance of the timing and frequency of water-level deviations diminishes, and migration rates revert back to a slope-SLR-dominated process.
Bibliographical noteFunding Information:
This work was supported by USGS Land Change Science Climate R&D Program and Ecosystems Program and NSF grant DEB-1832221 to the Virginia Coast Reserve Long Term Ecological Research project. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
- forest retreat
- marsh migration
- sea-level rise