What factors determine if an ecosystem will reestablish itself after a catastrophic event?

Explanation:

The factors that can determine if an ecosystem will reestablish itself after a catastrophic event depends on various facts. These facts include:-

1) The catastrophic event which occurred at the ecosystem.

2) The state of the catastrophic event. Was it a serious one or not?

3) The normal state of the ecosystem before the catastrophic event occurred.

4) The present state of the ecosystem after the catastrophic event had occurred.

5) The species that lived in that ecosystem and the amount of species which had been displaced.

6) The type of human involvement associated with the catastrophic event.

7) The future events which might occur after the catastrophic event. This could determine if the ecosystem might recover. These future events would be famine or drought and disease outbreak.

well, i believe that the answer is 2. : 3