In meromictic lakes, the number of turnovers of water per year is

Options

A. 1
B. 2
C. Many
D. Zero

Answer

### Step-by-Step Solution:

1. **Understanding Meromictic Lakes**:
- Meromictic lakes are a type of lake where the water layers do not mix. This means that the surface water and deep water remain separate and do not intermix.

2. **Characteristics of Meromictic Lakes**:
- In these lakes, the lack of mixing leads to distinct layers of water, often with different chemical compositions and temperatures.

3. **Turnover of Water**:
- The term "turnover" refers to the process of water mixing within the lake. In typical lakes (holomictic lakes), water can mix due to various factors like wind and temperature changes.

4. **Turnover in Meromictic Lakes**:
- Since meromictic lakes do not experience mixing of the water layers, the turnover of water in these lakes is effectively zero.

5. **Conclusion**:
- Therefore, the number of turnovers of water per year in meromictic lakes is **0**.

### Final Answer:
The number of turnovers of water per year in meromictic lakes is **0**.

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