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Succession is the act or process of following in order or sequence.
Political succession
In politics, succession refers to the ascension to power by one
politician or monarch after
another, usually in a clearly defined order.
For more information on specific succession procedures, see:
- Order of succession (royal)
- Presidential Succession Act (United
States)
- Succession planning (corporate)
Ecological succession
For the detailed treatment of this subject, see Ecological succession.
In ecology, succession refers to the replacement of one
biological community by another. Succession can be primary or
secondary. Primary succession occurs on essentially new substrata: bare rock or soil that has never
been colonised before. Examples would be sand dunes and lava flows. Secondary succession occurs on land which has been colonised before, but has been
disturbed back to some earlier state. Examples would include a drained reservoir,
cleared forest, or ploughed field.
Succession begins with arrival of the pioneer species and leads
eventually to establishment of a climax community. In primary
successions pioneer species are typically hardy plants that survive under harsh conditions. On English sand dunes, marram grass has deep roots to tap into the water table, rhizomes to bind the soil, and leaves that reduce water loss through transpiration. On lava flows the first plants to colonize are adapted to survive in thin or no soils and
possibly little water. The pioneer plants add organic matter to the soil, and help bind soil particles together, eventually
allowing other species to colonise the area. This process slowly enhances the soil quality, enabling a sequence of other
species assemblages to survive until a climax community is established. Climax communities are usually some form of woodland.
Musical succession
In music or music theory, a
succession is a series of any musical parameters including pitches, pitch classes, or simultaneities or simultaneity
successions. Succession may be thought of as a more general term for any possible progression, as in chord progression or
harmonic progression, though not all simultaneity successions are harmonic
progressions.
See also
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