Productivity in terrestrial ecosystems is affected by

Options

A. temperature
B. light intensity
C. availability of nutrients and water
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Productivity**:
- Productivity in ecosystems refers to the rate at which biomass is produced. It is a measure of how much organic matter is generated in a given area over a specific time period.

2. **Types of Productivity**:
- There are two main types of productivity:
- **Primary Productivity**: This is the rate at which plants (producers) create biomass through photosynthesis. It is measured in terms of the amount of organic matter produced per unit area over time.
- **Secondary Productivity**: This refers to the rate at which consumers (herbivores and carnivores) generate new organic matter by consuming the biomass produced by plants.

3. **Factors Affecting Productivity**:
- Several environmental factors influence productivity in terrestrial ecosystems:
- **Temperature**: Affects the metabolic rates of plants and the efficiency of photosynthesis.
- **Light Intensity**: Essential for photosynthesis; higher light intensity generally increases productivity.
- **Availability of Nutrients**: Nutrients such as nitrogen, phosphorus, and potassium are crucial for plant growth and biomass production.
- **Water Availability**: Water is vital for photosynthesis and overall plant health; insufficient water can limit productivity.

4. **Conclusion**:
- Given that productivity is influenced by temperature, light intensity, availability of nutrients, and water, the correct answer to the question is that productivity in terrestrial ecosystems is affected by **all of these factors**.

**Final Answer**: Productivity in terrestrial ecosystems is affected by temperature, light intensity, availability of nutrients, and water – all of these factors.

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