Download Carrying capacity

Carrying capacity
PI 6.1 MU 6.1d 6.1e
Bell ringer question
• List factors that can influence the
population size of ducks in Onondaga
Lake.
-Available food source
-Temperature
-The quality of water
-Etc
Exponential growth
Living organisms have the capacity to produce
populations of unlimited size, BUT….
http://www.britannica.com/EBchecked/media/158213/In-an-ideal-environment-populationsgrow-at-an-exponential-rate
Carrying capacity
…BUT environments and resources are
finite.
The number of organisms any habitat can
support (carrying capacity) is limited
• by the available energy, water, oxygen,
and minerals, and
• by the ability of ecosystems to recycle
the residue of dead organisms through
the activities of bacteria and fungi.
Logistic growth
The carrying
capacity (K) limits
the population
growth.
Abiotic factors
In any particular environment, the growth
and survival of organisms depend on the
physical conditions including
• Light intensity
• Temperature range
• Mineral availability
• Soil/rock type
• Relative acidity (pH)
An example of abiotic factor
• Certain fish species cannot live if dissolved
oxygen concentration in water drops below
a certain level.
As water quality
improves, more
species of fish appear.
http://pubs.usgs.gov/circ/circ1171/html/fishcom.htm
Bitoic factors
The survival of organisms also depends on
biotic factors such as
• the population of an individual species
• The interactions that a species has with
other species (e.g. predator/prey,
parasitism, commensalism, mutualism,
etc.)
Example of a biotic factor
• The population of lynx(predator) affects
the population of snowshoe hare (prey).
http://www.britannica.com/EBchecked/media/12/Cyclical-fluctuations-in-the-populationdensity-of-the-snowshoe-hare
Exit ticket
Exit ticket con’t