Nutrient entrichment of water body is

Options

A. Eutrophication
B. Stratification
C. Biomagnification
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the nutrient enrichment of a water body. We need to identify the correct term that describes this phenomenon.

2. **Identifying Key Terms**: The options provided are:
- Eutrophication
- Stratification
- Biomagnification
- None of the above

3. **Defining Eutrophication**: Eutrophication is the process where water bodies receive excess nutrients (like nitrogen and phosphorus), often from agricultural runoff. This leads to increased growth of algae (algal blooms) and other aquatic plants.

4. **Effects of Eutrophication**:
- The excess nutrients promote high primary productivity in the water, which can lead to an overgrowth of algae.
- As algae die and decompose, oxygen in the water is depleted, which can harm aquatic life, leading to fish kills and loss of biodiversity.

5. **Examining Other Options**:
- **Stratification**: This refers to the layering of water in a body based on temperature or density, not nutrient enrichment.
- **Biomagnification**: This is the process where the concentration of toxins increases in organisms at each successive level of the food chain, which is unrelated to nutrient enrichment.

6. **Conclusion**: Based on the definitions and effects discussed, the correct answer to the question "Nutrient enrichment of water body is" is **Eutrophication**.

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