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Everything you need to know about
Ecology
Ecology
–
the study of the living
and non-living things around us
Ecological Levels:
Organism
–
one living thing
(Ex: one fish)
Population
–
all the members of one
species in one area
(Ex: all
the cod in the Hudson River
Community
–
all the living things in
one area
(Ex: all the fish, crabs,
algae, bugs, etc. in the
Hudson River)
Ecosystem
–
all
the living and non-living things in one area
(Ex: all the fish, crabs, algae, bugs,
etc. in the Hudson River,
plus the
water, oxygen, carbon dioxide, sunlight, and
climate)
Biosphere
–
all of the ecosystems put
together
(Ex: Earth, including all the
rivers, ponds, meadows, deserts, mountains, etc.)
Parts of an Ecosystem
Everything in an ecosystem is divided
into two categories: biotic factors (living
things) and
abiotic factors (non living
things).
Abiotic Factors
?
Air
–
oxygen, carbon dioxide
?
Water
?
Rocks
?
Minerals and
chemicals
?
Climate
–
rainfall, sunlight, temperature
?
Soil
?
Shape of land
Biotic Factors
Type of organism
Definition
Examples
Synonyms and types
Producer
Makes its own food
Plants, algae
Autotroph
Consumer
Feeds on other
Cows, sharks,
Heterotroph
organisms
bears, humans
Herbivore
–
eats
producers
Carnivore
–
eats consumers
Omnivore
–
eats
producers and
consumers
Scavenger
–
eats
dead, decaying
animals
Decomposer
Eats dead
organisms
Bacteria, fungi
and returns nutrients
to the
soil
Relationships between
organisms
Predator-Prey: A
predator is a consumer that eats its prey. Energy
is transferred from prey to
predator.
Competition: There is a
limited amount of materials available in the
ecosystem. Organisms must
compete with
each other in order to survive.
Carrying Capacity: the number of
organisms an ecosystem can support. The carrying
capacity
depends mostly on the
availability of abiotic resources, as well as how
quickly decomposers can
return
nutrients to the soil. If the carrying capacity
is exceeded, organisms begin dying until the
carrying capacity is reached again.
Niche: The role a species
plays in a community. Only one species at a time
can occupy a niche.
Competition occurs
when two species try to occupy the same niche.
For example, birds that feed
in spruce
trees have a different niche than birds that feed
off of berries in shrubs.
A
food web
shows the transfer
of energy between many organisms in an ecosystem.
Arrows
point to the organism that gets
the energy (the one that eats).
This
food web shows
?
producers (trees, grasses, flower
seeds)
–
a producer has
all arrows pointing out
of it
?
consumers
(hawks, mountain lions,
grasshoppers,
mice, etc.)
–
a consumer has arrows
pointing into it,
and may have some
pointing out of it too
?
decomposers (bacteria, mushrooms)
–
a decomposer has all
arrows pointing
into it and usually
appears at the bottom
of the food web
A
food chain
is simpler than a
food web but shows the same type of relationships:
Trees
?
bark beetles
?
hawks
?
mountain lions
An
energy pyramid
is a diagram that shows the relationship between
organisms in an ecosystem.
The bottom
level represents organisms with the most energy
–
the producers. The top
level
represents organisms with the
least energy
–
the
carnivores. Energy decreases up the food chain
because energy is lost at each level
when the organisms use it or lose it as heat.