W3 Seminar: A moving-boundary perspective on coastal wetlands and barrier systems

Details

Speaker:
Jorge Lorenzo-Trueba, Ph.D., Associate Professor, Department of Geological Sciences, UF

Abstract:
Coastal wetlands and barrier environments evolve through shifting boundaries—shorelines, marsh edges, lagoon margins, and vegetation fronts—that respond to hydrologic forcing, sediment exchange, and ecological feedbacks. In my group, we use mathematical models of reduced complexity to track these moving boundaries in a way that isolates the key controls on long-term landscape behavior while keeping parameter requirements manageable. This moving-boundary framework provides a common language for examining diverse coastal settings and for connecting geomorphic processes with ecological responses.

I will highlight two applications of this approach. The first examines mangrove islands across the Caribbean, where interactions among evaporation, precipitation, soil-salinity gradients, and vegetation thresholds determine how far mangroves can extend into island interiors. By combining remote sensing, field-informed parameters, and an idealized salinity-dispersion model, we can explain observed patterns of die-back and project how shifts in hydrologic balance may reshape vegetated area.

The second application focuses on barrier–marsh–lagoon systems, using a reduced-complexity morphodynamic model to reconstruct the historical evolution of Long Beach Island, New Jersey. Tracking the coupled movement of the ocean shoreline, back-barrier marsh edge, and lagoon basin reveals how overwash, sediment fluxes, and human modification alter the pathways by which these systems migrate and reorganize.

Together, these examples illustrate how a moving-boundary perspective helps clarify the processes that govern wetland persistence and barrier-marsh-lagoon dynamics, and provides a flexible framework for exploring future landscape trajectories.