Question

Which statements accurately describe slow-flowing areas of streams and rivers? Check all that apply.

Slow-flowing areas usually contain a lot of oxygen.
Slow-flowing areas usually have warm water.
Slow-flowing areas are usually found near the source.
Slow-flowing areas usually have very clear water.
Slow-flowing areas usually support a lot of plant life.

Answer 1

Correct:
- Slow-flowing areas usually have warm water. (Slower water mixes less and warms more from sunlight.)
- Slow-flowing areas usually support a lot of plant life. (Low velocity allows rooted aquatic plants and algae to establish.)

Incorrect:
- Slow-flowing areas usually contain a lot of oxygen. (They generally have lower dissolved oxygen because of less turbulence and more decomposition.)
- Slow-flowing areas are usually found near the source. (Headwaters are typically faster-flowing; slow reaches are more common downstream or in floodplains.)
- Slow-flowing areas usually have very clear water. (They often accumulate sediments and organic matter and can be more turbid.)