What characterizes primary succession?

Primary succession is characterized by the development of a biological community in an area that initially lacks soil and organic material. This type of succession typically occurs following events such as volcanic eruptions or glacial retreat, where the landscape is stripped of all vegetation and soil. The absence of soil means that the first organisms to colonize the area are often pioneer species, such as lichens and mosses, which can survive in harsh conditions and contribute to soil formation over time.

In contrast, areas with rich soil are typically associated with secondary succession, where the soil remains intact after a disturbance such as a fire or a flood. The concept of soil being intact or disturbed is important in differentiating between primary and secondary succession. As for species extinction, while ecological changes can lead to extinctions, primary succession is more focused on community development and recovery rather than the loss of species. Thus, beginning in a location without soil or organic material is the defining characteristic of primary succession.