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Transcript limiting factor notes

LIMITING FACTOR
NOTES
HABITAT
 Habitat - type of environment in
which a particular species lives
 4 Components of a Habitat:
Water
Food
Shelter
Space
Survival of Species
A species’ long-term survival is possible only if
organisms can adapt to changes (in available
resources and their environment) and reproduce
 If an entire species is unable to respond to
changes, it could face extinction
 Extinct species – no living organism of the
species exists
 Endangered species – small population of the
species exists with an increased threat of
extinction

Limiting Factors


Biotic potential – a
population’s growth rate
under ideal conditions
Limiting Factor - any
biotic or abiotic factor in
an environment that
limits the size of a
population

Examples: Food, disease,
predators
TYPES OF LIMITING FACTORS


Density-dependent limiting factors – factors
that become limiting only when the number of
organisms per unit space reaches a certain level
 Ex. Space, disease, competition and
predation
Density-independent limiting factors – factors
that affect all populations in the same way,
regardless of their density
 Ex. Weather, seasonal cycles, natural
disasters and human activities
CARRYING CAPACITY
 Carrying
Carrying Capacity of Rabbits
# of Rabbits
Capacity
the maximum
population size
that a particular
environment can
support over time;
controlled by
limiting factors
70
60
50
40
30
20
10
0
1
2
3
4
5
6
Years
7
8
9
10
Ecosystem Stability

Changes in the environment, caused by
nature or humans, can affect the stability of
an ecosystem in positive or negative ways
 Example:
A volcanic eruption kills a
community’s populations of organisms – the
area’s ecosystem is destroyed
 Example: leaking septic systems release sewage
into a river, causing weed and algae growth,
which reduces the fish populations – humans
repair the leaks and ecosystem recovers