module8REVIEW

In this module, we learned that disturbances are events that can alter population sizes and community compositions of ecosystems. Watershed studies help scientists investigate how disturbances affect ecosystems; by manipulating watersheds, they can observe how the cycling of water and elements is altered. When a disturbance occurs, some ecosystems exhibit high resistance to the disturbance. Other ecosystems show high resilience, which allows them to bounce back quickly to pre-disturbance conditions. Finally, an ecosystem disturbance of intermediate magnitude favors a high diversity of species.

Module 8 AP® Review Questions

Question 1

1. Which is NOT true about disturbances?

  1. They are caused by natural events such as hurricanes.

  2. They occur only on short time scales.

  3. They can cause complete destruction of an ecosystem.

  4. Many result in no change in ecosystem productivity.

  5. Some are due to anthropogenic causes.

Question 2

2. An ecosystem that rapidly returns to its original state after a disturbance is

  1. resistant.

  2. vigorous.

  3. resilient.

  4. stable.

  5. adaptable.

Question 3

3. The intermediate disturbance hypothesis states that intermediate levels of disturbance will

  1. increase runoff.

  2. increase ecosystem nutrient cycling.

  3. decrease primary productivity.

  4. increase species diversity.

  5. decrease biomass.

Question 4

4. The Hubbard Brook experiment showed that

  1. the intermediate disturbance hypothesis is plausible.

  2. freshwater aquatic ecosystems are often very resilient.

  3. river restoration can take many years to complete.

  4. evapotranspiration increases with more vegetation cover.

  5. deforestation increases nutrient runoff.

Question 5

5. Which is a measure of how much a disturbance can affect the flows of energy and matter in an ecosystem?

  1. Diversity

  2. Intensity

  3. Resistance

  4. Resilience

  5. Homeostasis

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