The water held tightly by the soil particles around them is known as :

Options

A. Field capacity
B. Run away water
C. Hygroscopic water
D. Capillary water

Answer

**Step-by-Step Solution:**

1. **Understanding Soil Water Types**:
- Soil contains different types of water that can be categorized based on how they interact with soil particles. The main types are hygroscopic water, capillary water, and gravitational water.

2. **Defining Hygroscopic Water**:
- Hygroscopic water is the water that is held tightly to the soil particles in a thin film. This water is not available for plant uptake because it is bound too tightly to the soil particles.

3. **Identifying Other Types of Water**:
- Capillary water is the water that is held in the spaces between soil particles and is available for plants to absorb.
- Gravitational water is the excess water that drains through the soil and is not held by the soil particles.

4. **Understanding Field Capacity**:
- Field capacity refers to the amount of water that soil can hold after excess water has drained away. It includes all types of water: hygroscopic, capillary, and gravitational.

5. **Conclusion**:
- The water that is held tightly by the soil particles around them is specifically referred to as **hygroscopic water**.

**Final Answer**: The water held tightly by the soil particles around them is known as **hygroscopic water**.

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