The soil water available for absorption by plant roots is

Options

A. Rain water
B. Capillary water
C. Chemically bound water
D. Gravitational water

Answer

**Step-by-Step Solution:**

1. **Understanding Soil Water**: The question asks about the type of soil water that is available for absorption by plant roots. It is essential to recognize that plants absorb water and minerals primarily through their roots.

2. **Identifying the Source of Soil Water**: The soil water that is accessible to plants is found in the upper layers of the soil. This water is crucial for various metabolic processes in plants, including photosynthesis.

3. **Defining Capillary Water**: The water present in the upper soil layer exists in small spaces or pores between soil particles. These pores are often referred to as capillaries due to their tube-like structure.

4. **Choosing the Correct Term**: Among the options provided (rain water, capillary water, chemically bound water, and gravitational water), we need to identify which type of water is primarily available for plant absorption:
- **Rain Water**: While rainwater contributes to soil moisture, it is not consistently available throughout the year.
- **Capillary Water**: This is the water held in the soil's upper layer and is accessible to plant roots due to its presence in the capillary spaces.
- **Chemically Bound Water**: This water is not available for absorption as it is chemically bound to soil particles.
- **Gravitational Water**: This water drains through the soil and is not retained in the upper layers where roots can access it.

5. **Conclusion**: Based on the definitions and characteristics of each type of water, the correct answer is **capillary water**. This is the water that is readily available for absorption by plant roots.

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