What is the main difference between primary and secondary succession?

The main distinction between primary and secondary succession lies in the initial conditions of the environment where these processes occur. Primary succession takes place in lifeless areas that lack soil, such as after a volcanic eruption or on bare rock. In this scenario, the first organisms to colonize the area are often lichens and mosses, which can survive without soil and start the process of soil formation through the breakdown of rock and organic matter.

In contrast, secondary succession occurs in areas where an ecosystem has been disturbed but soil and some organisms still remain, such as after a forest fire, flood, or human activities like farming. This allows for faster recovery since there is an existing soil layer and some remaining seeds and organisms that can contribute to the recolonization of the area.

Understanding this difference is crucial in ecology, as it defines how ecosystems recover and develop over time following disturbances.