Question

Differentiate between primary and secondary succession and provide one example of each.

Answer 1

1. Primary succession (PS) takes a long time for completion, 1000 years or more while secondary succession (SS) takes a less time for completion 50-200 years.
2. PS occurs in an area which is barren or lifeless while SS occurs in an area which has been denuded recently and was previously inhabited.
   
3. Soil is absent at the beginning of PS and the environment is not suitable for sustaining normal life forms, Soil is present at the beginning of SS with some organisms.
   
4. There is no humus in the beginning as soil is absent in PS. In SS, humus is present from the very beginning by the decomposition of previous occupants.
   
5. Intermediary seral communities are many in PS, while in SS, intermediary seral communities are a few.
   
6. Reproductive structures or propagules of any previous community are absent in PS. In SS, reproductive structures of the previous occupants are present in the area.