Book 19, Question 129
Why Does a River Need Oxygen?
A river needs oxygen because fish, insects, and other river animals breathe it! The oxygen is dissolved in the water, mixed in invisibly. Without enough oxygen, river animals cannot stay healthy.
More fun facts
- Fish and other river life breathe oxygen dissolved in the water.
- Much of a river's oxygen comes from the air.
- Water plants add oxygen during the day.
- At night, plants stop making oxygen, so levels can drop sharply.
- Water temperature changes how much oxygen a river holds.
Sources: NASA, U.S. Geological Survey
Questions kids ask
Why can a river's oxygen drop at night?
Water plants stop making oxygen at night.