An ecological succession that begins in an area where no biotic community previously existed.

Prepare for your Environmental Science Exam 1 with our interactive quiz. Test your knowledge with various question types featuring detailed explanations. Start today and ace your exam!

Primary succession occurs when life begins in a place with no prior biotic community and no soil. It starts on bare rock, lava flows, or newly exposed land, where pioneering organisms like lichens and mosses colonize first. These pioneers help break down the substrate and add organic material, slowly building soil. As soil forms, more plants can establish, followed by larger communities over time. This contrasts with secondary succession, which happens after a disturbance in an area that still has soil and some organisms. Trophic level is about an organism’s position in a food web, not the start of a new community, and a phase shift refers to a major change in an ecosystem’s state, not the initial colonization process. So, the scenario described fits primary succession.