Which one is the edaphic factor of biosphere ?

Options

A. light
B. temperature
C. water
D. soil

Answer

To determine which one is the edaphic factor of the biosphere, we need to understand what edaphic factors are and how they relate to the environment.

### Step-by-Step Solution:

1. **Define Edaphic Factors**: Edaphic factors refer to the environmental factors related to the soil. They include the soil's physical and chemical properties, which influence the types of organisms that can thrive in a particular area.

2. **Understand Soil Structure**: The soil is composed of different horizons or layers:
- **O Horizon**: The top layer, rich in organic material.
- **A Horizon**: Also known as topsoil, it contains minerals and organic matter.
- **B Horizon**: Subsoil, where minerals leach from the upper layers accumulate.
- **C Horizon**: The layer of weathered rock and parent material.

3. **Identify Edaphic Factors**: Since edaphic factors are specifically related to soil, they include aspects such as soil texture, composition, moisture, pH, and nutrient content.

4. **Differentiate from Other Factors**:
- **Light**: An abiotic factor that comes from the sun, not related to soil.
- **Temperature**: Varies across different environments but is not a soil-related factor.
- **Water**: While important, it is not an edaphic factor as it can exist in various forms and locations.

5. **Conclusion**: The correct answer to the question is "Soil," as it is the primary edaphic factor that influences the biosphere by affecting the types of organisms that can live in a given area.

### Final Answer:
The edaphic factor of the biosphere is **Soil**.

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