Planetary boundaries
Topic: Natural Resources: Classification, Planning and Sustainable Use · NCERT: Beyond NCERT
Meaning
Planetary boundaries are nine safe limits for the Earth system. Johan Rockstrom and other scientists set them out in 2009. Each boundary marks a level of human pressure that the planet can take without risking sudden, harmful change. The nine include climate change, biosphere integrity (the health of living things), freshwater, nitrogen and phosphorus flows, ocean acidification and novel entities (new man-made substances such as plastics). The 2025 Planetary Health Check found that seven of the nine had been crossed (verify current).
Example
In Punjab, heavy use of nitrogen and phosphorus fertilisers has polluted groundwater with farm chemicals. This is a local case of the nitrogen and phosphorus boundary being pushed too far.
Don't confuse with
- The Limits to Growth (1972): a computer-model forecast of when unchecked growth would hit the planet's limits. Planetary boundaries instead name nine separate Earth-system limits and check whether each one has been crossed.