Water holding capacity of soil depends upon:

Options

A. size of its particles
B. type of parent rock
C. type of organisms
D. amount of organic matter

Answer

**Step-by-Step Solution:**

1. **Understanding Water Holding Capacity**: Water holding capacity of soil refers to the ability of soil to retain water against the force of gravity. It is crucial for plant growth and ecosystem sustainability.

2. **Factors Affecting Water Holding Capacity**:
- **Size of Soil Particles**: The size of the soil particles plays a significant role in determining how much water the soil can hold.
- **Large Particles**: Soils with larger particles (like sand) have larger pores, which allow water to drain quickly. This means they have lower water holding capacity.
- **Small Particles**: Soils with smaller particles (like clay) have smaller pores, which can hold water better due to capillary action. This results in a higher water holding capacity.

3. **Type of Parent Rock**: The type of parent rock influences the mineral composition and texture of the soil, but it is not the primary factor determining water holding capacity.

4. **Type of Organisms**: The presence of organisms in the soil (like earthworms or microbes) can affect soil structure and health but does not directly determine the water holding capacity.

5. **Amount of Organic Matter**: While organic matter can improve soil structure and increase water retention, the primary determinant of water holding capacity is still the size of soil particles.

6. **Conclusion**: The water holding capacity of soil primarily depends on the size of the soil particles. Smaller particles increase the soil's ability to retain water.

**Final Answer**: The water holding capacity of soil depends primarily on the size of the soil particles.

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