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An ecologist studied the effects of sewa...

An ecologist studied the effects of sewage effluent on the levels ofoxygcn concentration, bacteria and algae in a freshwater stream. The graph below is a summary of his findings. The sewage effluent entered the stream at point Y.

Which of the following can be the reason(s) for the rise in oxygen concentration between 4 km and 8 km downstream?

A

Increase in nitrates or organic matter

B

Decrease in bacteria population

C

Probable increase in aquatic plant population

D

Both B and C

Text Solution

Verified by Experts

The correct Answer is:
D
Both options B and C are correct.
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