In many temperate lakes, thermal energy from sunlight causes changes in the temperature of surface waters. These changes initiate a turnover, a mixing of waters that occurs in spring and fall.

Determine the correct order of events involved in seasonal turnover.

Drag the labels onto the flowchart of seasonal turnover. Labels may be used once, more than once, or not at all.

a. surface water warms to 4 C and sinks

b. water mixes, bringing oxygen to the bottom and nutrients to the surface

c. warm surface water is separated from cooler bottom water by thermocline

d. surface water cools to 4 C and sinks

e. water mixes, bringing oxygen to the bottom and nutrients to the surface

Question

Melanie Wagner

Biology

9 November, 22:30

In many temperate lakes, thermal energy from sunlight causes changes in the temperature of surface waters. These changes initiate a turnover, a mixing of waters that occurs in spring and fall.

Determine the correct order of events involved in seasonal turnover.

Drag the labels onto the flowchart of seasonal turnover. Labels may be used once, more than once, or not at all.

a. surface water warms to 4 C and sinks

b. water mixes, bringing oxygen to the bottom and nutrients to the surface

c. warm surface water is separated from cooler bottom water by thermocline

d. surface water cools to 4 C and sinks

e. water mixes, bringing oxygen to the bottom and nutrients to the surface

+1

Answers (1)

Know the Answer?

Darryl Cameron · Answer 1

Answer: The order is a-b-c-d-e-

Explanation:

In winter there is a thin layer of ice that covers the water of the lakes below. As spring approaches (a) surface water warms to 4 C and sinks. This eliminates the thermal stratification and (b) water mixes, bringing oxygen to the bottom and nutrients to the surface. In Summer, the lake presents again a clear thermocline profile as (c) warm surface water is separated from cooler bottom water. In the fall, (d) surface water cools to 4 C and sinks. This causes the lake water to mix once more (e) bringing oxygen to the bottom and nutrients to the surface.