Abstract
The valuable ecosystem services of salt marshes are spurring marsh
restoration projects around the world. However, it is difficult to
forecast the final vegetated area based on physical drivers. Herein, we
use a 3D fully coupled vegetation-hydrodynamic-morphological modeling
system (COAWST), to simulate the final vegetation cover and the
timescale to reach it from various forcing conditions. We found that
marsh formation can be divided in three distinctive phases: a
preparation phase characterized by sediment accumulation in the absence
of vegetation, an encroachment phase in which the vegetated area grows,
and an adjustment phase in which the vegetated area remains relatively
constant while marsh accretes vertically to compensate for sea level
rise. Sediment concentration, settling velocity, Sea Level Rise and
tidal range each comparably affect equilibrium coverage and timescale in
different ways. Our simulations show that The Unvegetated-Vegetated
Ratio (UVVR) also relates to sediment budget in marsh formation under
most conditions.