Earthworm increases the:-

Options

A. Salanity of soil
B. Acidity of soil
C. Fertility of soil
D. All of above

Answer

**Step-by-Step Solution:**

1. **Understanding Earthworm Behavior**: Earthworms are known for their burrowing habits. They consume soil and organic matter, which plays a crucial role in soil health.

2. **Soil Aeration and Structure**: As earthworms burrow through the soil, they create channels that improve soil aeration. This allows air and water to penetrate deeper into the soil, which is essential for root growth.

3. **Soil Mixing**: The burrowing action of earthworms helps in mixing different layers of soil. The topsoil, which is rich in organic matter, gets mixed with the lower layers, bringing nutrients closer to the surface.

4. **Fragmentation of Organic Matter**: Earthworms break down organic matter into simpler forms, making nutrients more accessible to plants. This process is vital for the recycling of nutrients in the ecosystem.

5. **Castings Production**: As earthworms move through the soil, they excrete castings. These castings are rich in nutrients and help to improve soil fertility. They also help in balancing the pH of the soil, reducing acidity and alkalinity.

6. **Conclusion**: Based on the above points, earthworms increase the fertility of the soil through their burrowing, mixing of soil layers, fragmentation of organic matter, and production of nutrient-rich castings.

**Final Answer**: Earthworms increase the fertility of the soil.

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