November 18, 1997
Vegetation in the Everglades
There is 830 species in all the ecological Everglades ( not just in the Park). 8% of these are endemics(about 51 species). 17% are exotics. The plants are being introduced here from the tropics like the Caribbean and from the temperate regions. The three big groups of plants found here are grasses, cypress spp., and orchids.
1) Upland species = 1 to 2 meters above surrounding area
A) Rockland Pine Forest: Pinus species
-High understory
(subcanopy) with pines, etc.
-Low understory
(mostly endemics)
B)Tropical Hardwoods: Carribbean tropical
type flora
2) Wetland Species
A) Aquatic Trees - ones that grow right in
the water such as Bayheads, Willowheads, Cypress heads, Pond Apple. A large
quanity of
organic matter accumulates here, get a small island where soil forms.
B) Sawgrass Marsh - (Cladium jamaicense)
grows through open parts of the Everglades with a cycle of approximately
five years
by fire. The Melaluca plant has started to invade this area ( it was introduced
in the 1920's from Australia). The
Melaluca sucks up an enormous amount of water. The Brazilian pepper, an
ornamental plant, has started to invade as
well.
3) Sloughs = drainage channels
A) submerged plants: find manatees, alligators,
tend to be more common in the South
Importance of Periphyton (attached algae and bacteria to leaves and
roots)
-collects silt and contributes an organic base to grazers on the periphyton
(small crustaceans, fish, and molluscs)
Oligotropic
P= 0.03 ppm (P = phosphorus) Phosphorus naturally low here, most is fixed
in plants.
Historically, in WCA, P input came from rain (118 tons/yr.), and overland
(11 tons/yr.) for a total of 129.
Presently, in WCA, P input still 118 from rain, but overland runoff gives
258 tons/yr for a total of 376 tons/yr. (most runoff from sugarcane farms).
Eutrophication
-take over by cattail
Historically, in the Everglades, input from rain was 78 t/y and only 10
t/y for a total of 88 t/y.
Currently, rain = 78 t/y
overland
= 11 t/y
total = 89 t/y
This has only increased a small amount.
Restoration of The Everglades (job offerings)
1) Fixing Hydrology: adjust flow rate and how and where it goes through,
instead of draining to ocean, allow it to drian through the park.
2) Fire: controlled burns, stop suppression of fires: let them burn
3) Control Exotic Plants: stop importation of anything new (control Melaluca)
4) Restore depth patterns
- Natural Hydrology Model: took into account -
rainfall patterns, sheet folw dynamics, and connections to hydrology
5) change agriculture
A) BMP's (Best Management Practices)
B) Sugar subsidies
C) Switch to aquatic plants- grow more things
like rice and field crops
-cut subsidies
-aquaculture
- fish farms
- ornamental
plant industry: aquarium plants
Real Problems, Starting Solutions
Endangered manatees and panther from boats, cars, habitat destruction.
Large animals, big home ranges, need lots of food.