Artificial ecosystems are characterised by

Options

A. high productivity
B. high diversity
C. complex food chain
D. more cycling of nutrients

Answer

**Step-by-Step Solution:**

1. **Understanding Ecosystems**: Ecosystems can be classified into two main types: natural ecosystems and artificial (or man-made) ecosystems. Natural ecosystems develop and sustain themselves without human intervention, while artificial ecosystems are created and maintained by humans.

2. **Characteristics of Artificial Ecosystems**:
- **Diversity**: Artificial ecosystems have lower biodiversity. This is because humans selectively breed or plant specific species, leading to a reduction in the variety of organisms present.
- **Food Chains**: The food chains in artificial ecosystems are typically short and less complex. This is due to the limited number of species that humans choose to include, resulting in fewer interactions between species.
- **Productivity**: Artificial ecosystems are characterized by high productivity. Humans optimize conditions by providing necessary nutrients and minerals, which enhances the growth and yield of the organisms present.
- **Nutrient Cycling**: Nutrient cycling is less efficient in artificial ecosystems. Unlike natural ecosystems, where nutrient cycling occurs naturally and effectively, artificial ecosystems often lack the diversity of organisms that contribute to a balanced nutrient cycle.

3. **Evaluating the Options**:
- **Option 1: High Productivity** - This is true for artificial ecosystems as they are designed for maximum yield.
- **Option 2: High Diversity** - This is false; artificial ecosystems have lower diversity.
- **Option 3: Complex Food Chain** - This is false; food chains are simpler and shorter in artificial ecosystems.
- **Option 4: More Cycling of Nutrients** - This is also false; nutrient cycling is less efficient in artificial ecosystems.

4. **Conclusion**: Based on the characteristics discussed, the correct answer to the question "Artificial ecosystems are characterized by" is **Option 1: High Productivity**.

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