Secondary successions
In the event of the destruction of a community, a secondary succession begins in it – a slow process of restoration of the initial state. Secondary succession lasts for several decades.
Secondary successions develop in the place of formed biocenoses after their disruption.
Example: overgrowing of an abandoned field, meadow, burning or deforestation, etc.
Secondary succession begins with the appearance of annual herbaceous plants on the vacated soil area.
These are typical weeds: dandelion, sow thistle, coltsfoot and others. Their advantage is that they grow rapidly and produce seeds adapted to be spread over long distances by wind or animals.
However, after two or three years they are being replaced by competitors – perennial grasses, and then – shrubs and trees, primarily aspen.
These rocks shade the ground, and their extensive root systems take all the moisture from the soil, making it difficult for the seedlings of the first species to hit the field. However, the succession does not stop there: a pine tree appears behind the aspen; and the latter – slowly growing shade-tolerant species, such as spruce or oak.
A hundred years later, on this site, the community is being restored, which was in the place of the field before the reduction of forests and plowing of the land.
