Question

A facultative pond system is employed for wastewater treatment. Which of the following statements is/are true:

• A. The dissolved oxygen concentration will be high during daytime compared to night-time.
• B. The pH will be high during daytime compared to night-time.
• C. The dissolved oxygen concentration will be low during daytime compared to night-time.
• D. The pH will be low during daytime compared to night-time.

Hint:

In aquatic environments like facultative ponds, the balance between oxygen production during the day and consumption during the night directly influences both dissolved oxygen levels and pH.

Answer 1

The Correct Option is A, B

During daytime, photosynthesis takes place, and algae produce oxygen while consuming CO$_2$. This leads to an increase in the dissolved oxygen concentration. Additionally, the pH increases due to the consumption of CO$_2$ and the release of oxygen.
Therefore:
- The dissolved oxygen concentration will be high during daytime compared to night-time.
- The pH will also be high during daytime compared to night-time.
Thus, the correct answers are (A) and (B).