Different species of plants occupy various levels in the forest ecosystem. Such distribution is called _________.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the distribution of different species of plants at various levels within a forest ecosystem.

2. **Identifying Key Terms**: The key terms in the question are "different species of plants," "various levels," and "forest ecosystem." These terms indicate that we are looking for a specific ecological concept related to how plants are arranged or distributed in a forest.

3. **Exploring Forest Ecosystems**: In a forest ecosystem, plants are not randomly distributed. Instead, they occupy different layers or levels based on their height, size, and light requirements.

4. **Defining Stratification**: The term that describes this layered arrangement of plants in a forest is called "stratification." Stratification refers to the vertical distribution of different plant species in an ecosystem, where each layer has distinct types of plants.

5. **Examples of Stratification**: In a typical forest, the stratification can be observed as follows:
- **Trees**: The tallest plants, forming the uppermost layer.
- **Shrubs**: Shorter than trees, forming the middle layer.
- **Herbs**: Ground-level plants that are typically low in height.
- **Grasses**: Often found in the understory or forest floor.

6. **Conclusion**: Therefore, the answer to the question is that the distribution of different species of plants occupying various levels in a forest ecosystem is called "stratification."

**Final Answer**: Stratification

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