Soil erosion is prevented by

Options

A. afforestation
B. overgrazing
C. removal of weeds
D. increasing birds population

Answer

**Step-by-Step Solution:**

1. **Understanding Soil Erosion**: Soil erosion is the process by which the top layer of soil is worn away due to various factors such as water, wind, and human activities like tilling or ploughing. This can lead to the loss of fertile land and negatively impact agriculture.

2. **Identifying Causes of Soil Erosion**: The primary causes of soil erosion include deforestation, overgrazing by livestock, and the excessive use of fertilizers. These activities can destabilize the soil, making it more susceptible to erosion.

3. **Role of Vegetation in Preventing Erosion**: One of the most effective ways to prevent soil erosion is through afforestation, which involves planting trees. The roots of trees help to anchor the soil, reducing the likelihood of it being washed or blown away.

4. **Evaluating Other Options**:
- **Overgrazing**: This practice can lead to soil degradation and erosion, as it removes vegetation that holds the soil in place.
- **Removal of Weeds**: While weeds can compete with crops, their removal does not directly prevent soil erosion and can sometimes exacerbate the problem by leaving soil exposed.
- **Increasing Bird Population**: While birds can contribute to the ecosystem, their population increase does not directly prevent soil erosion.

5. **Conclusion**: The most effective method to prevent soil erosion is through afforestation, as it involves planting trees that stabilize the soil and prevent it from being washed away.

**Final Answer**: Soil erosion is prevented by **afforestation**.

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