Which of the following zones of lakes receives diffuse light at or below light compensation point?

Options

A. Limnetic zone
B. Euphotic zone
C. Disphotic zone
D. Profundal zone

Answer

To determine which zone of a lake receives diffuse light at or below the light compensation point, we need to understand the characteristics of the different zones of a lake and the concept of the light compensation point.

### Step-by-Step Solution:

1. **Understand the Light Compensation Point**:
- The light compensation point is the light intensity at which the net oxygen production is zero. This means that the amount of oxygen produced through photosynthesis is equal to the amount consumed through respiration. Below this point, photosynthesis cannot occur effectively.

2. **Identify the Zones of a Lake**:
- Lakes are typically divided into several zones:
- **Littoral Zone**: The shallow area near the shore where light penetrates to the bottom.
- **Limnetic Zone**: The open water area that is well-lit and supports photosynthesis.
- **Photic Zone**: This includes the upper layers of the water where there is enough light for photosynthesis. It is further divided into:
- **Euphotic Zone**: The upper layer of the photic zone where light is sufficient for photosynthesis.
- **Dysphotic Zone**: The lower part of the photic zone where light is present but insufficient for photosynthesis.
- **Profundal Zone**: The deeper part of the lake where light penetration is minimal, and it is below the light compensation point.

3. **Analyze Each Zone for Light Reception**:
- **Littoral Zone**: Receives ample light due to its shallow depth.
- **Limnetic Zone**: Also receives significant light as it is part of the open water.
- **Euphotic Zone**: Receives enough light for photosynthesis, above the light compensation point.
- **Dysphotic Zone**: Receives some light but not enough for photosynthesis; it is at or below the light compensation point.
- **Profundal Zone**: This is the deepest part of the lake, where light is very limited and typically below the light compensation point.

4. **Conclusion**:
- Among all the zones discussed, the **Profundal Zone** is the correct answer as it is the zone that receives diffuse light at or below the light compensation point.

### Final Answer:
The zone of the lake that receives diffuse light at or below the light compensation point is the **Profundal Zone**.