Why does ecological succession occur?

Ecological succession occurs due to the changes in the physical environment and population of species. It may also occur when the conditions of an environment suddenly and drastically change. For example, forest fires, wind storms, and human activities all greatly alter the conditions of an environment. 

It can be explained as follows – 

1. Every species has a set of environmental conditions under which they grow and reproduce most optimally.
2. As long as the ecosystem’s set of environmental conditions remains constant, those species optimally adapted to those conditions will flourish. 
3. The “engine” of succession, the cause of ecosystem change, is the impact established species have upon their own environments. 
4. A consequence of living is the sometimes subtle and sometimes overt alteration of one’s own environment. 
5. The original environment may have been optimal for the first species, but the newly altered environment is often optimal for some other species of plant or animal. 
6. Under the changed conditions of the environment, the previously dominant species may fail and another species may become ascendant.

Further Readings – 

1. Species in News
2. Alien Invasive Species 
3. Weather, Climate And Climate Change