Which of the following is an ecosystem service provided by a natural ecosystem?

Options

A. Cycling of nutrients
B. Prevention of soil erosion
C. Pollutant absorption and reduction of the threat of global warming
D. All of the above

Answer

To determine which of the following options is an ecosystem service provided by a natural ecosystem, we need to analyze each option given:

1. **Cycling of Nutrients**:
- Natural ecosystems play a crucial role in the cycling of nutrients. This process involves the movement and exchange of organic and inorganic matter back into the production of living matter. Nutrient cycling is essential for maintaining soil fertility and supporting plant growth.

2. **Prevention of Soil Erosion**:
- Natural ecosystems, particularly those with dense vegetation, help to prevent soil erosion. The roots of plants hold the soil in place, reducing the impact of wind and water that can lead to erosion. This is a vital service as it maintains soil health and prevents land degradation.

3. **Pollution Absorption and Reduction of Threat of Global Warming**:
- Natural ecosystems, especially forests and wetlands, absorb pollutants from the air and water. They also play a significant role in carbon sequestration, which helps mitigate the effects of global warming. This service is crucial for maintaining environmental quality and combating climate change.

4. **All of the Above**:
- Since all the previous options (cycling of nutrients, prevention of soil erosion, and pollution absorption) are recognized ecosystem services provided by natural ecosystems, the correct answer must encompass all these services.

**Conclusion**:
Based on the analysis of each option, the correct answer is **D) All of the above**. All listed options represent ecosystem services provided by natural ecosystems.