Remote Sensing Based Modeling of Salt Marsh Stability Under Sea Level Rise

Abstract

Salt marshes provide important ecosystem services to coastal communities and environments. However, increasing rates of sea level rise threaten vital ecosystems. For marshes to keep up with sea level rise they must gain elevation at a similar rate, which depends on how vegetation responds to changing water depths. Here we use multi-scale remote sensing to evaluate a model of marsh dynamics, finding that vegetation exhibits an initial decrease in aboveground biomass with depth, followed by an increase, and eventually a decrease beyond an optimal depth. Our results support key aspects of an existing model but challenge its simplicity, showing instead more spatial variability that may be attributed to differences in water properties including nutrient and salinity levels as well as sediment concentration. We demonstrate that remote sensing can improve large-scale modeling, which is critical for coastal management.