Which of the following ecosystems is most productive in terms of net primary production?

Options

A. Deserts
B. Tropical rainforests
C. Oceans
D. Estuaries

Explanation

To determine which ecosystem is the most productive in terms of net primary production (NPP), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Net Primary Production (NPP)**:
- NPP is defined as the amount of organic material (biomass) produced by plants after accounting for the energy used in respiration. It can be calculated using the formula:
\[ \text{NPP} = \text{Gross Primary Productivity (GPP)} - \text{Respiration} \]

2. **Identify the Ecosystems Provided**:
- The ecosystems listed in the question are:
- Desert
- Tropical Rainforest
- Oceans
- Estuaries

3. **Research or Recall Average NPP Values for Each Ecosystem**:
- Tropical Rainforest: Approximately 1500 grams per square meter per year
- Oceans: Approximately 125 grams per square meter per year
- Estuaries: Typically have high productivity, but for this question, we will focus on the provided options.
- Desert: Approximately 90 grams per square meter per year

4. **Compare the NPP Values**:
- Tropical Rainforest: 1500 g/m²/year
- Oceans: 125 g/m²/year
- Estuaries: Not provided, but generally higher than oceans and deserts.
- Desert: 90 g/m²/year

5. **Determine the Most Productive Ecosystem**:
- Based on the NPP values, the tropical rainforest has the highest NPP at 1500 g/m²/year, making it the most productive ecosystem among the options given.

6. **Conclude the Answer**:
- Therefore, the ecosystem that is most productive in terms of net primary production is the **Tropical Rainforest**.

### Final Answer:
The most productive ecosystem in terms of net primary production is the **Tropical Rainforest**.

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