Question

How does the biological oxygen demand get affected with the increased presence of organic matter in water?

• A. the oxygen demand increases
• B. the oxygen demand decreases
• C. the oxygen demand remains unchanged
• D. None of the above

Answer 1

The correct option is A

the oxygen demand increases

Biochemical oxygen demand (BOD) is the amount of dissolved oxygen needed (i.e., demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. Hence the biological oxygen demand increases because the microbes demand more oxygen to degrade the increased organic content in the water.