Succession

Primary Succession The processes involved in changing an area from one lacking any community (no plants, no animals, no insects, no seeds, AND NO SOIL) to one consisting of individuals, populations, communities, and ecosystems. Starts WITHOUT SOIL. This is the confusing part - there may have been a previous community, but if a disturbance removes or in some way covers the soil so only mineral substrate is left to support pioneer plants we would classify it as Primary succession. No organic matter, only mineral material (e.g. sand, bare rock, gravel from glacial outwash, volcanic ash and lava.

Primary Succession Pioneer Plants Lichens and Mosses

Primary Succession Examples: Bare Rock Volcanic Eruption Glacier (Glacial Retreat) Man-made structures

Secondary Succession Follows disturbance of an existing community that removes or damages the vegetation, but does not remove, destroy, or cover the soil. Starts WITH SOIL.

Secondary Succession Pioneer Species The first plants to become established after the disturbance start from roots or seeds remaining in the soil or from seeds carried in by wind or animals from surrounding communities.

Secondary Succession Causes Human Disturbance Natural Disturbance Abandoned Pastures Natural Disturbance Floods Hurricanes Fires