What is an Ecosystem?

Ecosystem = a community of

organisms interacting with their physical

environment

Ecosystems include biotic (living) components:

• Plants• Animals• Bacteria• Fungi• Algae

CO2Ecosystems include abiotic (non-living)

components:•Wind•Water•Soil•Rock

•Sun•Gases•Temperature

Ecosystems include processes:

•Respiration•Fire•Photosynthesis•Seed dispersal•Food web•Erosion

•Deposition•Water Cycle•Evapotranspiration•Evaporation•Percolation

Ecosystems have no specific scale

Ecosystems are not static

Ephemeral Wetland

• Ephemeral pond• Temporary pond• Cypress dome• Prairie wetland• Isolated wetland• Seasonal depression• Carolina bay

Dry Periodically

Biotic Components

• Witchgrass• Maidencane• St. John’s

wort• Sawgrass• Sundew• Pond cypress• Black gum

• Predacious diving beetle• Green darner• Mole cricket• Least killifish• Eastern

mosquitofish• Ornate

chorus frog

• Striped newt• Oak toad• Chicken

turtle• Cottonmouth• Wood duck• Raccoon• White-tailed

deer

Abiotic Components

• Rain• Soil• Limestone• Sun

• Wind• Oxygen• Carbon Dioxide• Nitrogen• Temperature

Processes / Interactions

• Evapotranspiration• Evaporation• Photosynthesis• Respiration• Predation• Percolation• Erosion

• Deposition• Run-off• Metamorphosis• Migration• Fire• Reproduction

Seasonal Changesin water levels

Winter: high rainfall + little evapotranspiration (no leaves on trees) = water in the wetlands

Spring: little rainfall, trees leafing out (evapotranspiration), sun becoming stronger (evaporation) = wetlands dry

Summer: rainfall amounts are greater than evaporation, evapotranspiration – wetlands have water

Fall: little rainfall, evaporation and evapotranspiration high due to high temperature, strong sunlight, photosynthesis = wetlands dry

Climate Change

Changes in the timing and amount of rainfall will affect ephemeral wetland-breeding amphibian species. For example:• Flatwoods salamanders normally migrate to

ephemeral wetlands to breed in October and November and lay their eggs at the edge of the dry wetland basin. December rains hydrate the wetland. When the water level reaches the eggs, the eggs hatch and the larvae grow up in the wetland. If rain doesn’t fall until February, the eggs would dry out before the wetland hydrates.

Ecological SuccessionMany ephemeral wetlands are marshes. This

means the vegetation is predominately herbaceous. Amphibians depend on herbaceous vegetation – they lay their eggs on grass blades, larvae use herbaceous vegetation for cover and they eat the algae that grows on the vegetation.

When there is no fire in the system or during times of drought, woody vegetation (tree seedlings and shrubs) moves in and changes the ephemeral wetland from a marsh wetland to a swamp.

Woody vegetation shades out the herbaceous vegetation and can reduce wetland water levels through evapotranspiration. Lower water levels mean less larval habitat and also increases the chance that wetlands go dry before larvae grow enough to metamorphose.

BIG CONCLUSION1. Ecosystem = a community of organisms

interacting with their physical environment

2. Ecosystems = biotic component + abiotic component + interactions/processes

3. Ecosystems do not have a specific scale

4. Ecosystems are not static – they can be impacted by seasonal variation, climate change, and ecological succession

Now it’s Your Turn

1. Longleaf pine tree2. Pitcher plant bog3. Coral reef4. Pine flatwoods5. Lake Wales Ridge scrub6. Mangrove swamp7. Coastal beach8. A Florida springrun9. The Everglades10. Pine Rocklands