Download • Describe the three general methods used by ecologist to study

13.2 Biotic and Abiotic Factors
Bell Ringer
• Describe the three general methods
used by ecologist to study organisms.
• (Be sure to include key similarities
and differences)
13.2 Biotic and Abiotic Factors
KEY CONCEPT
Every ecosystem includes both living and nonliving
factors.
13.2 Biotic and Abiotic Factors
An ecosystem includes both biotic and abiotic factors.
• Biotic factors are living things.
– plants
Animals
Ex.?
– fungi
– bacteria
plants
13.2 Biotic and Abiotic Factors
• Abiotic factors are nonliving things.
– moisture
– temperature
– wind
– sunlight
– soil
sunlight
moisture
13.2 Biotic and Abiotic Factors
• The balance of these factors determine which organisms
can survive in an environment.
13.2 Biotic and Abiotic Factors
• Case study: In the
Caribbean Sea
coral reefs near
marshes have
more fish than
reefs father out.
– Mangroves are
the key biotic
factors.
– Oxygen levels
& salinity are
the abiotic
factors.
13.2 Biotic and Abiotic Factors
• “What are the differences between biotic & abiotic
factors?”
13.2 Biotic and Abiotic Factors
Changing one factor in an ecosystem can affect many
other factors.
• Biodiversity is the assortment, or variety, of living things in
an ecosystem.
– The amount of biodiversity is dependent on factors like
temp & moisture.
• Rain forests have more biodiversity than other locations in
the world, but are threatened by human activities.
13.2 Biotic and Abiotic Factors
• A keystone species is a species that has an unusually large
effect on its ecosystem.
keystone
13.2 Biotic and Abiotic Factors
• Keystone species form and maintain a complex web of life.
Ex.?
creation of
wetland
ecosystem
increased waterfowl
Population
keystone species
increased
fish
population
nesting
sites for
birds
13.2 Biotic and Abiotic Factors
• The loss of a single species may cause a ripple effect
across an entire ecosystem.
13.2 Biotic and Abiotic Factors
“Explain why the Pacific Salmon, could be considered a
keystone species.”