Least productive ecosystem is

Options

A. Grassland
B. Savannah
C. Forest
D. Tundra

Answer

**Step-by-Step Solution:**

1. **Understanding Ecosystem Productivity**: Ecosystem productivity refers to the rate at which energy is produced in an ecosystem, typically measured in grams of biomass per square meter per year. Different ecosystems have varying levels of productivity based on factors such as climate, soil type, and vegetation.

2. **Analyzing the Given Options**: The question provides four ecosystems: grasslands, savanna, forests, and tundra. We need to evaluate the productivity of each to determine which one is the least productive.

3. **Evaluating Forests**: Forest ecosystems are known for their high productivity due to abundant rainfall and diverse plant life. They typically have the highest productivity among the ecosystems listed.

4. **Evaluating Grasslands**: Grasslands have a productivity range of 200 to 1000 grams per square meter per year. They are characterized by open areas with few trees and can support a variety of grasses and herbaceous plants.

5. **Evaluating Savanna**: The savanna ecosystem, which is a mixed grassland ecosystem characterized by the trees being sufficiently small or widely spaced apart so that the canopy does not close, has moderate productivity levels, but it is generally higher than that of tundra.

6. **Evaluating Tundra**: The tundra ecosystem has the lowest productivity, with levels around 90 grams per square meter per year. This is primarily due to its extreme climate, with low temperatures, limited sunlight, and a short growing season. The soil in tundra regions is often permafrost, which further limits plant growth.

7. **Conclusion**: After evaluating all the ecosystems, it is clear that the tundra has the least productivity among the options provided.

**Final Answer**: The least productive ecosystem is the tundra.

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