Choose odd one out w.r.t. functional aspects of ecosystem.

Options

A. Energy flow
B. Decomposition
C. Species composition
D. Nutrient cycling

Answer

To solve the question of choosing the odd one out with respect to the functional aspects of an ecosystem, we need to analyze the options given: energy flow, decomposition, species composition, and nutrient cycling.

### Step-by-Step Solution:

1. **Understanding Ecosystem Functions**:
- An ecosystem consists of living organisms (biotic factors) and non-living components (abiotic factors) that interact with each other. The functional aspects of an ecosystem refer to the processes that maintain its structure and function.

2. **Identifying the Options**:
- **Energy Flow**: This refers to the transfer of energy through the food chain, from producers to consumers and decomposers. It is a fundamental process in ecosystems.
- **Decomposition**: This is the process by which organic matter is broken down into simpler substances, returning nutrients to the soil and making them available for plants. It is essential for nutrient cycling.
- **Nutrient Cycling**: This involves the movement and exchange of organic and inorganic matter back into the production of living matter. It is crucial for maintaining ecosystem health.
- **Species Composition**: This refers to the variety and abundance of different species within an ecosystem. While it is important for biodiversity, it does not directly describe a functional process like the others.

3. **Analyzing the Odd One Out**:
- The first three options (energy flow, decomposition, and nutrient cycling) are all processes that describe how energy and nutrients move through an ecosystem. They are functional aspects that directly contribute to the ecosystem's operation.
- **Species Composition**, on the other hand, describes the variety of species present but does not describe a functional process. It is more about the structure of the ecosystem rather than its function.

4. **Conclusion**:
- Therefore, the odd one out with respect to the functional aspects of an ecosystem is **Species Composition**.

### Final Answer:
**Species Composition** is the odd one out.

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