Primary succession: succession that starts where no living organisms are there- these could be areas where no living organism ever existed may be a bare rock or new water body.
Secondary succession: succession that starts in areas that somehow, lost all the living organisms that existed there.
Primary succession occurs in:
- newly cooled lava,
- bare rock,
- Newly created pond or reservoir.
Secondary succession begins in areas where natural biotic communities have been destroyed such as
- In abandoned farm lands.
- Burned or cut forest,
- land that have been flooded
Since some soil or sediment is present, secondary succession is faster than primary succession.