Which type of succession occurs after a disturbance that destroys a community but leaves the soil intact?

• A. Ecological succession
• B. Primary succession
• C. Secondary succession
• D. Pioneer species

Answer: (C)

The scenario tests the difference between primary and secondary ecological succession and how soil presence guides the recovery process. When a disturbance destroys a community but leaves the soil intact, the ecosystem can rebound from seeds, roots, and soil organisms that survive or reside in the soil. This rapid reestablishment from an existing soil seed bank and surviving root systems is secondary succession. It tends to proceed faster than primary succession because the foundational medium—soil—already exists and can support regrowth and recolonization right away.

Think of primary succession as starting from scratch on bare rock or new land with no soil, where pioneer organisms must build soil itself before other species can establish. In secondary succession, the ecosystem has a head start because the soil remains, along with some living organisms, enabling quicker recovery to a mature state if conditions remain suitable. Pioneer species describe the first colonizers in the early stages, but they are not a type of succession themselves; they occur in both primary and secondary contexts as the initial players in the rebuilding process.