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Ecological Succession. Succession : when old populations in an ecosystem are gradually replaced by new populations. This is a predictable change. Succession can be from a natural disaster or human activity.
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Succession: when old populations in an ecosystem are gradually replaced by new populations. • This is a predictable change
Succession can be from a natural disaster or human activity.
1. Primary Succession – occurs where no soil exists (rock & ash) …newly exposed surfaces.
Primary succession can occur because of: • Glaciers • Volcano eruption
Primary Succession cont. Pioneer species: 1st species to occupy an area. Ex – lichens (fungus & algae)
2. Secondary Succession -restarts succession at a different point than that which occurs with primary succession.
Succession proceeds at a quicker pace during secondary succession since soil is already pre-formed and ready for use by plants.
Secondary succession can occur because of: • forest fires • disease & pests
climate changes (hurricane, drought) • human disturbances (clear cutting,
A mature, stable community is known as a climax community. One in which the populations of all organisms are in balance w/ each other & existing abiotic factors.