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How does primary succession begin on bare rock or newly formed volcanic islands?
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community ecology
Energy transfer and heat loss along a food chain.
Primary succession is the process by which a biological community first colonizes a barren, lifeless habitat, such as bare rock or a newly formed volcanic island, where soil is initially absent or incapable of supporting life.123
The process typically begins as follows:
- Initial Colonization: Microorganisms, such as bacteria, are often the first to arrive. They are followed by pioneer species—such as lichens and mosses—which are adapted to harsh, nutrient-poor environments.41
- Soil Formation: As these pioneer species grow, they release acids that chemically break down the rock. When they die and decompose, their organic remains mix with the fragmented rock particles, gradually creating the first pockets of soil.41
- Community Development: Once soil is present, wind-dispersed seeds from weedy, fast-growing plants like grasses can germinate. As these plants die and decay, they further enrich the soil, allowing more complex species, such as shrubs and trees, to become established.134
- Succession: Over time, animal species arrive, and the ecosystem becomes increasingly complex until it reaches a relatively stable climax community.13