River Health

Water with high turbidity 

• is cloudy and hard to see through
• is clear

The amount of flowing dirt in the water is 

• pH
• suspended sediment
• biodiversity
• dissolved oxygen

High turbidity indicates poor water quality because

• it clogs the gills of aquatic animals and makes it difficult to breathe
• it makes it hard for sun to get to the aquatic plants
• it makes it hard for aquatic animals to find their food
• all are reasons high turbidity indicates poor water quality

an important element for fish and other aquatic animals to live

• dissolved oxygen
• substrate
• brackish water
• algae

Which would a scientist expect to find in a lake that experienced a sudden increase in nitrate levels?

• an increase in temperature
• an increased number of fish
• an increase in dissolved oxygen
• an increased amount of algae and aquatic plants

How do nitrate levels affect the health of a water system?

• As nitrates decrease, there is an increase in plant growth
• nitrates cause bacteria to consume large protein molecules
• nitrates cause aquatic organisms to die due to oxygen depletion
• as nitrates increase, there is an increase in dissolved oxygen

When water is moving rapidly, the amount of dissolved oxygen _________________.

• increases
• decreases
• stays the same

When the temperature of water increases, the amount of dissolved oxygen _________________.

• increases
• decreases
• stays the same

How does discharge from sewer pipes affect the amount of dissolved oxygen in a river?

• It heats up the water and increases the amount of dissoved oxygen.
• It cools down  the water and decreases the amount of dissolved oxygen.
• It increases bacteria growth and decreses the amount of dissolved oxygen.
• It decreses bacteria growth increases the amount of dissolved oxygen.

If the water in a river has a pH of 12 it is considered to be ___________.

• acidic
• basic
• neutral