2.5.3—Success HLion definition
- Syllabus
- First assessment 2026
- Objective
- 2.5.3
- Level
- HL
Separate Succession through Time from Zonation across Space
Succession is community replacement over time in one area; zonation is community difference across space at a given time.
Succession can be driven by organisms changing soil, shade and nutrients, plus disturbance. Zonation is read along a spatial gradient such as height or moisture.
A bare field becoming shrubland over 20 years is succession; different plant bands from beach to dune are zonation.
The time dimension; without repeated observations, a spatial snapshot may only show zonation.
Do not infer succession just because communities differ; ask whether the same place changes through time.