SMA 9 E.1.3, 1.4

How is the number of individuals in a biological indicator species population related to the health of the water system?

• If the number of individuals shows a steady decline, the health of the water system is also declining.

• If the number of individuals shows a steady increase, the pollution in the water system is also increasing.

• As the number of individuals increases, the population becomes a better biological indicator species.

• As the number of individuals decreases, the population becomes a better biological indicator species.

Which is the best tool to determine if a recent algal bloom has made the water too basic for aquatic organisms?

• a dissolved-oxygen meter

• thermometer

• a turbidity tube

• pH meter

Which best explains why fertilizer runoff is bad for a river?

• It changes the river’s color.

• It changes the river's odor

• It promotes algae growth in the river.

• It poisons animals living in the river

Which best describes the relationship between dissolved oxygen and fish?

• Low dissolved oxygen causes fish to die, but high dissolved oxygen causes fish to thrive.

• Low dissolved oxygen causes fish to thrive, but high dissolved oxygen causes fish to die.

• Low dissolved oxygen has no effect on fish, but high dissolved oxygen causes fish to migrate.

• Low dissolved oxygen causes fish to migrate, but high dissolved oxygen has no effect on fish.

Which summarizes the relationship between agricultural fertilizer runoff and nitrates in a body of water?

• As runoff increases, nitrate levels increase.

• As runoff increases, nitrate levels decrease.

• As runoff decreases, nitrates cause algae populations to decrease.

• As runoff decreases, nitrates cause water temperatures to increase.

How do elevated turbidity levels affect the health of a water system over time?

• Excessive sediment can improve food gathering by visual feeders.

• Turbid waters become cooler, causing oxygen levels to rise.

• Settled particles smother eggs of fish and aquatic insects.

• Photosynthesis increases, causing excessive algae growth.

Which is the best way for a city to monitor the effects of a new factory built on a riverbank for pollution?

• Check pH levels of the river water daily.

• Set up a sewage treatment plant downstream.

• Check regularly for dead fish and other wildlife in different parts of the river after the factory is built.

• Set a baseline toxicity level for the water before the factory is built then test the water on a regular basis.

An increase in the turbidity in a lake is most likely the result of which human activity?

• increase vehicle travel

• improper wildlife management

• introduction of foreign species

• increased land clearing for development

Which best explains why nonpoint pollution is so hard to control?

• Nonpoint pollutants have no odor.

• Nonpoint pollutants are more toxic.

• Nonpoint pollutants are all gaseous and invisible.

• Nonpoint pollutants come from a variety of locations.

Which would have a positive impact on the biodiversity of a large lake?

• air pollution and land clearing

• thermal pollution and water mismanagement

• thermal pollution and water

• regular monitoring and cleanup of subaquatic vegetation