During the process of ecological succession, the changes that take place in communities are

Options

A. orderly and sequential
B. random
C. very quick
D. not influenced by the physical environ- ment

Answer

**Step-by-Step Solution:**

1. **Understanding Ecological Succession**: Ecological succession is the process through which ecosystems change and develop over time. It involves a series of progressive changes in the structure and composition of a biological community.

2. **Orderly and Sequential Changes**: The changes that occur during ecological succession are not random; they follow a specific order. For example, in plant succession, the process typically begins with pioneer species such as lichens and mosses, followed by more complex plants like algae, bryophytes, pteridophytes, and eventually leading to gymnosperms and angiosperms.

3. **Pioneer and Climax Communities**: The first community that establishes itself in a barren environment is called the pioneer community. Over time, as conditions change, this community gives way to more complex communities, ultimately leading to a climax community, which is more stable and adapted to the local environment.

4. **Gradual Changes Over Time**: The changes in communities during succession are gradual and can take millions of years. This long time frame emphasizes that ecological succession is a slow process rather than a quick one.

5. **Influence of Physical Environment**: The changes in communities during ecological succession are influenced by the physical environment. Factors such as climate, soil type, and availability of water play significant roles in determining which species will thrive at different stages of succession.

6. **Conclusion**: Therefore, the changes that take place in communities during ecological succession are orderly and sequential, influenced by the physical environment, and occur over a long period.

**Final Answer**: The changes that take place in communities during ecological succession are orderly and sequential.

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