Ecosystem can be recognised as self-regulating and self sustaining unit of:-

Options

A. Species
B. Landscape
C. Organism
D. Community

Answer

**Step-by-Step Solution:**

1. **Understanding the Ecosystem**: An ecosystem is a community of living organisms (plants, animals, microorganisms) interacting with their physical environment (soil, water, climate).

2. **Self-Regulating Nature**: An ecosystem is considered self-regulating because it can maintain its balance and stability through various feedback mechanisms. For example, predator-prey relationships help control population sizes, ensuring that no single species dominates the ecosystem.

3. **Self-Sustaining Characteristics**: An ecosystem is self-sustaining as it can support itself without external inputs. This means that the energy flow (usually from the sun) and nutrient cycling (through decomposition and recycling of organic matter) are sufficient to maintain the system.

4. **Identifying the Correct Unit**: The question asks for the unit that can be recognized as self-regulating and self-sustaining. The options provided include species, landscapes, and communities.

5. **Evaluating Options**:
- **Species**: Refers to individual organisms and does not encompass the interactions and relationships necessary for self-regulation and sustainability.
- **Communities**: A group of different species living together, but they still rely on the larger ecosystem for resources and do not fully encapsulate the self-sustaining aspect.
- **Landscapes**: These are larger areas that include multiple ecosystems and are influenced by climate and geography. They can be self-regulating and self-sustaining due to their complex interactions and diversity.

6. **Conclusion**: Based on the evaluation, the correct answer is landscapes, as they represent a broader unit that can maintain itself and regulate its internal processes.

**Final Answer**: Landscapes

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