Productivity, Decomposition, energy flow and nutrient cycling are the :-

Options

A. Physical structure of ecosystem
B. Functions of ecosystem
C. Only Biotic components of ecosystem
D. Only Abiotic components of ecosystem

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- **Productivity:** Refers to the rate at which energy is produced in an ecosystem, typically through photosynthesis in plants.
- **Decomposition:** The process by which organic substances are broken down into simpler organic matter, often involving bacteria and fungi.
- **Energy Flow:** The transfer of energy through a food chain, from producers to consumers and decomposers.
- **Nutrient Cycling:** The movement and exchange of organic and inorganic matter back into the production of living matter, involving various nutrients.

2. **Identifying the Nature of These Processes:**
- These four processes (productivity, decomposition, energy flow, and nutrient cycling) are essential ecological processes that describe how ecosystems function.

3. **Evaluating the Options:**
- The question asks whether these processes are part of the physical structure of the ecosystem or its functions.
- **Physical Structure:** Refers to the abiotic components such as air, water, land, and soil.
- **Functions of the Ecosystem:** Refers to the processes that occur within the ecosystem, including how energy and nutrients are cycled.

4. **Conclusion:**
- Since productivity, decomposition, energy flow, and nutrient cycling describe how an ecosystem operates rather than its physical components, they are best categorized as functions of the ecosystem.

5. **Final Answer:**
- Therefore, productivity, decomposition, energy flow, and nutrient cycling are the **functions of the ecosystem**.

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