In other terms, the question goes like this:
How are we speeding up the effects of the Competitive Exclusion Principle and thereby altering the outcome of that ecosystem's natural succession?
When the Ecosystem contains plants only, one species of plant out-competes the others and take over this illustrates the Competitive Exclusion Principle , which theorizes that no 2 species can occupy the same niche at same time particular location if resources are limited. The presence of humans or consumers is needed to keep that plant in check and allow the other specie to survive.
The producers are the harbingers of primary succession. As these pioneer plants die and decay, they add organic material to the soil, which allow a secondary succession.