Question

what type of succession occurs when there is no usable soil in an ecosystem? tertiary succession primary succession secondary succession

Explanation:

To determine the type of succession with no usable soil, recall ecological succession types:

• Primary succession starts on bare rock/lack of soil (e.g., after volcanic eruptions, glacier retreats), where soil must form from scratch.
• Secondary succession occurs after a disturbance (e.g., fire, logging) that leaves soil intact.
• "Tertiary succession" is not a recognized ecological term.

Since the question specifies "no usable soil," primary succession matches this scenario.

Answer:

B. primary succession