Unit 8 Lesson 4 Florida's Ecosystems
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Unit 8 Lesson 4 Florida's Ecosystems
Florida Benchmarks
• SC.7.N.1.1 Define a problem from the seventh
grade curriculum, use appropriate reference
materials to support scientific understanding, plan
and carry out scientific investigations of various
types, such as systematic observations or
experiments, identify variables, collect and
organize data, interpret data in charts, tables, and
graphics, analyze information, make predictions,
and defend conclusions.
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Unit 8 Lesson 4 Florida's Ecosystems
Florida Benchmarks
• SC.7.L.17.3 Describe and investigate various
limiting factors in the local ecosystem and their
impact on native populations, including food,
shelter, water, space, disease, parasitism,
predation, and nesting sites.
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Unit 8 Lesson 4 Florida's Ecosystems
Pushing THE LIMIT
What limits the size of populations?
• When the environment cannot support more
individuals, a population will stop growing.
• A limiting factor is an environmental factor that
keeps a population from reaching its full potential
size.
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Unit 8 Lesson 4 Florida's Ecosystems
What limits the size of populations?
• Both living and nonliving environmental factors
can limit the size of a population.
• Only one factor at a time can limit a population.
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Unit 8 Lesson 4 Florida's Ecosystems
What limits the size of populations?
• Suppose an area has enough food for 500
armadillos and enough water for 1,000 armadillos.
Food is a limiting factor.
• If the area suddenly had enough food for 2,000
armadillos, the population would not grow to
2,000 armadillos.
• Water would be the limiting factor. Only 1,000
armadillos could survive.
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Unit 8 Lesson 4 Florida's Ecosystems
What are introduced species?
• Species that naturally live in an ecosystem are
called native species.
• Introduced species are species that have been
brought to an ecosystem by humans.
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Unit 8 Lesson 4 Florida's Ecosystems
What are introduced species?
• Many introduced species are successful because
they don’t have predators, parasites, or diseases
in the new habitat.
• Some introduced species may be better
competitors for resources, or even eat the native
species.
• Many species have been introduced to Florida,
including Burmese pythons.
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Unit 8 Lesson 4 Florida's Ecosystems
Land, HO!
What are Florida’s land ecosystems?
• Many species live in Florida’s land ecosystems.
Different factors limit populations in these
ecosystems.
• Florida’s prairies are dominated by plants such as
grasses, sedges, and rushes.
• In prairies, fires aid the growth of grasses but
limit the growth of trees. Herbivores can limit
plant populations.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s land ecosystems?
• Florida’s forests include trees such as longleaf
pines, mangroves, cypress, and cabbage palms.
• Light, space, and nutrients limit tree and plant
populations.
• Many animals live in forests. Predators often are
limiting factors.
• Fire harms some forest species and benefits
others.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s land ecosystems?
• Most beaches in Florida are sandy. Many animals
live in burrows under the sand.
• Birds eat the animals that live in the sand and
others that wash up on the beach. Birds can be
limiting factors for some animals.
• Beaches are also nesting sites for sea turtles and
birds.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s land ecosystems?
• Dunes are formed from sand blown from the
beaches.
• Low-growing plants can survive the spray from
salt water here, but the steep slopes limit the size
of plants that can grow on the dunes.
• Dunes are important nesting places for birds.
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Unit 8 Lesson 4 Florida's Ecosystems
Gator COUNTRY
What are Florida’s freshwater
ecosystems?
• Freshwater ecosystems include lakes, ponds,
rivers, and wetlands.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s freshwater
ecosystems?
• Lakes and ponds are standing bodies of water.
• Some plants float on top of the water, and others
grow in shallow areas.
• The amount of oxygen in lakes and ponds limits
the sizes and kinds of populations that can be
supported.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s freshwater
ecosystems?
• Rivers and streams have flowing water and are
home to many organisms, including manatees.
• Shelter is often a limiting factor in rivers and
streams.
• Rocks provide hiding places from predators and
shelter from rapid currents.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s freshwater
ecosystems?
• The Florida Everglades are wetlands, areas
where land is covered by water for at least part of
the year.
• Animals and trees rely on hammocks, which are
areas that are dry most of the year.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s freshwater
ecosystems?
• Many birds, fish, reptiles, and mammals live in
wetlands.
• Wetland plants remove waste and pollution from
water.
• Nutrients limit plant populations in wetlands.
• Low oxygen levels and drying up of wetlands limit
fish populations.
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Unit 8 Lesson 4 Florida's Ecosystems
Just Add SALT!
What are Florida’s marine ecosystems?
• Florida’s marine, or saltwater, ecosystems support
many species.
• These marine ecosystems are at risk from
development and pollution, which can limit
populations.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s marine ecosystems?
• One of the most diverse marine ecosystems is the
coral reef, which grows in waters that are warm,
shallow, and clear.
• Coral reefs are made up of the skeletons of tiny
animals called corals.
• A coral reef can be home to thousands of species.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s marine ecosystems?
• Sunlight and water depth are limiting factors for
coral.
• Space, high temperatures, and polluted water are
limiting factors for many species.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s marine ecosystems?
• Many streams and rivers flow into the ocean,
forming estuaries. An estuary is an area where
fresh water mixes with salt water.
• Many organisms, such as birds, turtles, and
alligators, rely on the nutrients provided by
estuaries.
• Nutrients, water movement, and salt levels are
limiting factors for various species.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s marine ecosystems?
• Salt marshes are found along the coast. Grasses
and other plants live in these areas.
• Salt marshes are occasionally flooded by tides,
which can limit plant populations.
• Salt levels, nutrients, and oxygen levels limit
various populations.
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Unit 8 Lesson 4 Florida's Ecosystems
What are Florida’s marine ecosystems?
• Mangrove swamps are found in areas that are
flooded by tides and also receive freshwater
runoff.
• They are dominated by mangrove trees, whose
roots often reach below the water.
• Salt levels, nutrients, and temperature are limiting
factors for mangrove swamps. The amount of time
the area is wet or dry also is a limiting factor.
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