The type of ecosystem with the highest mean plant productivity is :

Options

A. Desert
B. Temperate grassland
C. Tropical rain forest
D. Tundra

Answer

To determine the type of ecosystem with the highest mean plant productivity, we can analyze the options provided:

### Step-by-Step Solution:

1. **Identify the Ecosystem Types**: The question provides four options: Desert, Temperate Grassland, Tropical Rainforest, and Tundra.

2. **Evaluate Each Ecosystem**:
- **Desert**: Deserts are characterized by low rainfall and arid conditions. As a result, the net primary productivity (NPP) in deserts is very low due to limited water availability and harsh conditions for plant growth.

- **Temperate Grassland**: While temperate grasslands do have some productivity, it is generally lower than that of tropical rainforests. Grasslands can support a variety of grasses and some flowering plants, but they do not reach the productivity levels seen in tropical ecosystems.

- **Tropical Rainforest**: Tropical rainforests are known for their high biodiversity and dense vegetation. They receive abundant rainfall throughout the year, which creates ideal conditions for plant growth. The NPP in tropical rainforests is the highest among all ecosystems due to the combination of warm temperatures and high moisture levels.

- **Tundra**: The tundra is characterized by cold temperatures, short growing seasons, and limited vegetation. The harsh climate results in very low plant productivity, making it one of the least productive ecosystems.

3. **Conclusion**: After evaluating all the options, it is clear that the Tropical Rainforest has the highest mean plant productivity due to its favorable climate and abundant resources for plant growth.

### Final Answer:
The type of ecosystem with the highest mean plant productivity is **Tropical Rainforest**.

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