Download Lesson 02- Population and Carrying Capacity kw

Lesson 02 ­ Population and Carrying Capacity April 23, 2014
Population and Carrying Capacity
Read p. 55 in your text and fill in the blanks using the word bank
one species
• Population: all the members of _____________________ that occupy a certain area during a ____________________.
certain time
•Carrying Capacity
Ex. The population of bass in Lake Ontario
maximum
'Carrying capacity' refers to the _________________ population size of sustain
a particular species that a given ecosystem can _________________ .
When a population is maintained at its carrying capacity, the size of the population is at an __________________. A biodiverse equilibrium
ecosystem can maintain an equilibrium. Which of the following curve(s) shows the existence
of a carrying capacity? __________
Population Density
1
2
3
Time
What does the dotted line represent? _________________________
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Lesson 02 ­ Population and Carrying Capacity April 23, 2014
Limiting Factors
Carrying Capacity can be affected by limiting factors such as:
1. Amount of available water and energy (food)
­ If the population grows too large it will eventually crash when food runs out.
Provide an example:
2. Predation
­ If the population grows too large, predators will reduce the size of the population of prey.
Provide an example:
Pull
3. Competition
­ If resources become scarce, members of a population compete for resources. The more energy an organism spends on competing, the less energy it has for growth and reproduction.
­ This limits the size of a population.
Provide an example:
4. Space
­ If a population grows too large, space will run out. Competition for space will reduce the population.
Provide an example:
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Lesson 02 ­ Population and Carrying Capacity April 23, 2014
Investigating Moose and Wolf Populations
Part 1: Nutrients
Graph the results of the simulation for moose and wolf populations over the ten year period. Use your graph to answer the following questions, using complete sentences.
1. What effect did the forest fire initially have on the moose population? Why?
2. How could the moose population change from zero to four from year 1 to year 2? 3. Is there a relationship between moose and wolf populations? If so, explain it.
4. What other factors might be present that might account for changes in the populations?
5. Predict what might happen to the moose and wolf populations over the next ten years under the same circumstances.
Part 2: Space
Graph the results of the simulation for moose and wolf populations over the ten year period. Use your graph to answer the following questions, using complete sentences.
1. The amount of available space was cut in half, but the moose and wolf populations declined by more than half. Predict why this might be.
2. Is there a relationship between moose and wolf populations? If so, explain it.
3. What other factors might be present that might account for changes in the populations?
4. Predict what might happen to the moose and wolf populations over the next ten years under the same circumstances.
Part 3: Predators
Graph the results of the simulation for moose and wolf populations over the ten year period. Use your graph to answer the following questions, using complete sentences.
1. What effect do the bears have on the available food for the moose? What effect do the bears have on the available food for the wolves?
2. What other factors might be present that might account for changes in the populations?
3. Explain what happened to the ecosystem in the years 7 through 10.
4. Predict what might happen to the moose and wolf populations over the next ten years under the same circumstances.
Part 4: Summary
The simulation showed a simplified version of an actual ecosystem. Wolves prey on white­tailed deer and beaver as well as moose. If the moose population declines, wolves have other prey to sustain them. Moose feed on aquatic vegetation, assorted ground plants, leaves, and twigs of both conifers and deciduous trees and shrubs. If one food source becomes unavailable, there are others that will sustain the moose population. Biodiversity is the existence of a wide variety of plant and animal species in their natural environments. With reference to this investigation and your graphs, explain why biodiversity is important for the sustainability of ecosystems.
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