Explain the term secondary succession.

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When an area is cleared, as for agriculture and then abandoned, the dominant ecosystem of the area will generally return through a series of well defined stages. Since this is the re-establishment of an ecosystem that was originally present, the process is called secondary succession. In secondary succession, a fertile soil base is present at the start. If this has been destroyed by erosion or other means, it may be necessary for the system to start over in a manner similar to primary succession.

W plant community maybe disturbed causing some plants to be destroyed, as from a. fire or from human logging or cultivation. If the disturbance stops, the community will begin a secondary succession, changes in the vegetation that will lead back to a climax community.
Thus, secondary succession begins with a disturbance such as Fire, Hurricane, Flood, and Pollution leading to scorched remains of a developed community. The fertile soil (which is left largely undisturbed by the disturbance) allows for the secondary succession process to 'proceed much faster than from the primary succession which begins with barren rocks/sand. Also, some species are actually prompted by the effects of such disturbances to reproduce (release their seeds). One example Serotiny releases its seeds when a resin surrounding its pine cone melts in the presence of fire.
Often R selected species are dominant due to high rates of reproduction and efficient methods of dispersal, which due to change abiotic conditions paves the way for K select species. R selected species are mainly herbaceous species which have shorter generation period and faster growth rate.
Secondary succession involves few progressive stages. First to re-colonize devastated communities grow from seeds carried by air or animal. With nutrient-rich soil already present, the first stage of secondary succession is characterized by herbaceous species that predominate the community. These herbaceous species (including annuals and perennials) sprout up after a disturbance from root crowns and underground stems, prompting the cycle of regrowth.
Second are woody shrubs, which succeed the herbaceous species, have good dispersal methods, and have fast rates of reproduction. These factors, accompanied by relatively short i growth periods allow woody shrubs to predominate in a developing community.
Like in the final .stage of primary succession, the K-selected species of secondary succession pre-dominate the community, after developing over significant periods of time (due to their slow rate of growth). Compared to the r-selected species they are better competitors and come to consume much of the sunlight of the community (the limiting factor). Similar to primary succession, the presence of trees signifies a mature, climax community.

marto answered the question on March 20, 2019 at 07:33

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Explain the term secondary succession.

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