Why is ecology not limited only to the forces of nature?

Ecology is not limited to the forces of nature because –

1. Over time, it has been modified by human activities.

2. The calamities like being flood prone or global warming, which appear to be the natural feature of the environment are often created by human intervention.

3. The ecological changes can be brought by natural as well as human factors but it is not easy to separate and distinguish that which ecological change is the result of natural factors and which is the result of the human factors.