Nudation - Processes in Succession

The first step or requirement is the availability of the right kind of habitat, primary succession takes place in a bare area, that is, without any life form; and secondary succession occurs in area where soil is already formed, but the vegetation is destroyed. The bare area may develop due to several causes, some of them are:

1. Topographic -factors like soil erosion by gravity, water or wind, may destroy the existing vegetation thus creating a bare area. Other topographic causes include deposition of sand, landslide and volcanic activity.
2. Climatic - glaciations, long dry periods, hails and storm, frost and fire are the agents that destroy vegetation.
3. Biotic - One important agent is man that causes destruction of forests, grasslands and other stretches of vegetation for agriculture, industry, housing and several other purposes. Overgrazing by animals, diseases caused by organisms like bacteria, fungi and insects too destroy vegetation of an area to produce bare areas.