Primary succession
This section covers primary succession from newly exposed land through colonisation by pioneer species.
Starting with a new habitat
Succession is the gradual change in the community of an ecosystem over time. As succession proceeds, both the organisms present and the abiotic conditions change.
Primary succession begins on newly formed or exposed land where there is initially no established community.
Examples include bare rock exposed after lava has cooled and land exposed when a lake dries up. These starting conditions are hostile and provide little or no developed soil.
Pioneer species
Seeds and spores can reach the exposed surface, including by being carried in the wind. The first organisms able to establish are the pioneer species, commonly including lichens and mosses.
When pioneer organisms die and decay, organic material accumulates and contributes to the formation of a basic soil. This begins to alter the conditions for species that colonise later.
Initial conditions
- newly exposed land
- little or no developed soil
- hostile conditions for many species
Early colonisers
- seeds and spores reach the area
- pioneer species establish first
- death and decay begin soil development