For tree and grassland ecosystems, pyramid of biomass is

Options

A. Upright
B. Inverted
C. Spindle -shaped
D. Urn-shaped

Answer

To answer the question regarding the pyramid of biomass in tree and grassland ecosystems, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Pyramid of Biomass**:
- The pyramid of biomass represents the relationship between different trophic levels in an ecosystem and the biomass present at each level. It helps visualize how much living material (biomass) is available at each trophic level.

2. **Identify the Ecosystems in Question**:
- The question specifically mentions tree and grassland ecosystems. These ecosystems are characterized by their primary producers (trees in forests and grasses in grasslands).

3. **Determine the Structure of the Pyramid**:
- The pyramid of biomass can be either upright or inverted. An upright pyramid indicates that the biomass decreases as you move up the trophic levels, while an inverted pyramid indicates that the biomass increases at higher trophic levels.

4. **Analyze the Trophic Levels in Tree and Grassland Ecosystems**:
- In tree ecosystems, trees (primary producers) have a large biomass. Herbivores (like insects and birds) that feed on these trees have less biomass compared to the trees. As you move up to carnivores that feed on herbivores, the biomass continues to decrease.

5. **Conclusion**:
- Since in both tree and grassland ecosystems, the biomass decreases as you move up the trophic levels (from producers to herbivores to carnivores), the pyramid of biomass is upright.

### Final Answer:
For tree and grassland ecosystems, the pyramid of biomass is **upright**.

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