2.1.22—Human impacts on stability
- Syllabus
- First assessment 2026
- Objective
- 2.1.22
- Level
- SL
A tipping shift occurs when disturbance plus reinforcing feedback pushes an ecosystem beyond recovery to its previous stable state.
Show threshold → feedback → persistent new conditions. In deforestation, less transpiration lowers rainfall, raising fire and mortality risk and causing more tree loss.
A forest becomes drier after tree loss; fires then remove more trees, shifting toward a different equilibrium.
No. Show self-reinforcing change and a persistent shift toward another state.
Large disturbance alone does not prove a tipping point.