Which of the following best describes the main difference between primary succession and secondary succession?

• A. Primary succession occurs on newly formed or exposed surfaces where no soil exists, while secondary succession occurs in areas where a disturbance has left the soil intact.
• B. Primary succession involves only animal colonization, while secondary succession involves only plant colonization.
• C. Primary succession results in less biodiversity than secondary succession.
• D. Primary succession happens after a forest fire, while secondary succession happens on volcanic lava flows.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the concept of ecological succession. Ecological succession is the process by which ecosystems change and develop over time. It can be categorized into two types: primary succession and secondary succession.
2. Step 2: Define primary succession. Primary succession occurs in areas where there was previously no soil or life, such as newly formed volcanic lava flows or areas exposed by retreating glaciers. It begins with pioneer species, like lichens and mosses, that can colonize bare surfaces and contribute to soil formation.
3. Step 3: Define secondary succession. Secondary succession occurs in areas where a disturbance (e.g., forest fire, flood, or human activity) has disrupted an existing ecosystem but left the soil intact. It typically progresses faster than primary succession because the soil already contains nutrients and seeds.
4. Step 4: Compare the two types of succession. The main difference is that primary succession starts from bare surfaces without soil, while secondary succession starts in areas where soil is already present. This distinction is crucial for understanding the recovery process of ecosystems.
5. Step 5: Evaluate the options provided in the problem. Based on the definitions and comparison, identify the correct description of the main difference between primary and secondary succession. Eliminate incorrect options by checking if they align with the scientific definitions of these processes.