Salt marsh Restoration
Salt marshes
are protected coastal wetlands which function as a
transitional zone from the land to salty/brackish
water. Salt marshes are commonly referred to as
tidal marshes because they naturally occur in the
intertidal (littoral) zone. This area fluctuates
with the tides with marsh beds being exposed to the
air at low tide and submerged at high tide. Marshes
are dominated by halophytic (salt tolerant) plants.
The dominant emergent grass in the Southeastern
United States is smooth cord grass (Spartina
alterniflora). The zone directly above the
intertidal zone is dominated by black needle rush (Juncus
roemerianus). The higher/dryer areas of the
marsh contain much more biodiversity; one example of
a plant commonly found in this zone is salt meadow
cord grass (Spartina patens).
Coastal salt
marshes are regarded as one of the most biologically
productive ecosystems in the world. The marsh’s
energy is driven by the breakdown of marsh grasses
into small plant particles called “detritus”. The
detritus is broken down by bacteria which then fuels
the food web, beginning with phytoplankton (algae)
and moving to zooplankton (microscopic animals),
invertebrates and estuarine fishes. The food web of
the salt marsh also extends outward to include
larger open-water fishes, local and migratory birds,
and marine mammals. Salt marshes also provide
shelter and serve as an excellent nursery ground for
a large variety of marine species. The grasses
provide camouflage for juvenile fish and
invertebrate species, and also help to protect
against larger predators.
Beyond their
biological importance, salt marshes help to protect
our shorelines from erosion, provide a nursery and
feeding ground for ~70% of Florida’s commercially
valuable fisheries (fish, shellfish) and improve
water quality by filtering excess nutrients and
pollutants which enter our watershed from land-based
runoff.
Before and after shoreline restoration at Grande Lagoon
Salt marshes
in Northwest Florida were abundant in the past but
due to natural processes and adverse human
influences they have consistently degraded. Salt marshes naturally
establish in areas of low wave energy. Many areas
of Northwest Florida where marshes once existed
would benefit from the implementation of a
restoration project however these areas are often
exposed to high wave energy as the result of the
disappearance of historical oyster reefs. In order
to achieve maximum protection for a newly created
salt marsh from wave energy, increase biodiversity,
and create a living shoreline, several different
restoration projects are combined with salt marsh
restoration. These include the installation of
oyster reef breakwaters and the the reintroduction
of seagrass beds (SAV) into areas of historical
abundance. These projects can be large in scale,
such as Project GreenShores in Pensacola Bay, which
consists of 15 acres of salt marsh
habitat, or they may be on the order of less than an
acre. In an effort to promote the functionality of
living shorelines to the public in Northwest
Florida, we are currently in the pilot phase of a
project to restore several marsh areas on privately
owned lands suffering from erosion, as well as
continuing to restore marsh areas on publicly owned
lands.
Additional Information
Support Provided by the Following Organizations:
EPA Gulf of Mexico Program
Florida Coastal Management Program
National Fish and Wildlife Foundation
National Oceanic and Atmospheric Administration
U.S. Fish and Wildlife Service
Northwest District -Salt Marsh Restoration Program
