Transcript Limiting Factors Presentation

Limiting Factors in an
Ecosystem
A look at one species:
The Green Tree Frog (GTF) Hyla cineria
Limiting Factors
Environmental factors (either biotic or abiotic)
that prevent a population from increasing
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Biotic factors are related to, caused by, or produced by living
organisms.
Abiotic factors are not associated with the activities of living
organisms.
Let’s identify some of the limiting factors in the environment,
and describe how they affect the Green Tree Frog (GTF).
Types of Limiting Factors
Biotic Factors
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Food
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Predation
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Disease
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Parasitism
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Invasive species
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Competition
Abiotic Factors
Water
 Living Space
 Global Warming
Combos Biotic/Abiotic Factors
 Habitat Destruction
 Shelter
 Soil
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Availability of Food
A basic need of all organisms to obtain
energy from the environment
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If food is not available, organisms may not reproduce
and/or may starve
• Green Tree Frogs eat crickets, moths, flies, other small
invertebrates
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•Biotic Factor
Water
The right quantity and quality of water is a
basic need of all organisms
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Quantity of water: GTFs and frogs in general must have
enough water to maintain the moisture in their wet/moist skins
and to reproduce.
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Water Quality: is a measure of how clean the water is for the
organisms that use it.
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Most frogs lay their eggs in water, and need it for their tadpoles to
hatch and grow.
Frogs are considered good bioindicators of water quality since they
cannot survive polluted water because of their permeable skins.
urnAbiotic
factor
Shelter
A basic need of all organisms to find a suitable place to
take refuge from the weather, to hide from predators,
to sleep, to raise young, etc.
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GTFs prefer trees, bushes, and human houses where they
consume insects attracted by light sources after dark.
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Shelter may be biotic (like trees), abiotic (like rocks), and/or
man-made (like houses).
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Abiotic/Biotic factor
Living Space
A basic need of all organisms to
have a certain amount of space
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Sometimes called territory
Must be large enough to meet organism’s basic
requirements such as finding food, water, shelter,
mates, etc.
Usually related to an organism’s size
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Abiotic factor
Predation
An organism preys on and
consumes animals
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Green Tree Frogs are eaten by large spiders,
birds, snakes, and even larger frogs (such as
the invasive species Cuban Tree Frogs).
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Biotic factor
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Competition
Organisms compete to acquire the resources
to live and reproduce successfully
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Compete for food, water, shelter, space, mates, and other needs
Within their own species (other Green Tree Frogs)
With other similar species (Barking Tree Frogs, Squirrel Tree
Frogs)
With unlike species (spiders and birds)
With invasive species (Cuban Tree Frogs)
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Biotic factor
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Habitat Destruction
Loss of habitat through climate change,
urbanization, and other factors
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The number one reason that organisms become
endangered is habitat loss
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Habitats of Green Tree Frogs include wet prairies,
cypress swamps, and hydric hammocks as well as
borders of lakes and streams, areas with floating
vegetation or moist conditions, and occasionally in
brackish waters.
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Biotic, abiotic and man made factors
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