Key Idea: Most marks in topic 1.3 come from footprints and biocapacity, and from judging how sustainable a place is. Learn those first, then the models.
1. Footprints and biocapacity (most marks)
- An ecological footprint is the land and water a population needs for its resources and its waste.
- Biocapacity is what an area's land and water can actually supply and absorb.
- A footprint bigger than the biocapacity is unsustainable: the population depends on imports or runs nature down.
- On a graph, give the figures, the trend and the year the lines cross.
2. How sustainable is this place?
- The last Paper 1 question [6] asks you to judge a place from the resource booklet.
- Give evidence for and against, each with a reason, up to [4] on each side.
- End with a conclusion that weighs the two sides [1].
3. The big ideas and models
- Sustainability has three pillars: environmental, social and economic.
- Sustainable development meets today's needs without harming future generations.
- The SDGs, planetary boundaries, the doughnut and the circular economy each have uses and limitations: learn two of each.
How it is examined:
| Question | How to score |
|---|---|
| [1] to [3] Read a footprint and biocapacity graph | Quote figures and years; say which line is higher and what that means. |
| [6] To what extent is this place sustainable? | Evidence for and against from the booklet, each with a reason, then a conclusion. |
| [4] to [7] Evaluate the ecological footprint | Strengths, limitations, and a judgement: it adds many things into one number. |
| [2] to [4] Name or use a sustainability model | Use the model's own words, such as the nine planetary boundaries. |
Key terms, one line each:
| Term | In one line |
|---|---|
| Sustainability | using a system so it can keep going and future generations are no worse off |
| Environmental justice | everyone's right to a clean environment and a fair share of resources |
| Ecological footprint | the land and water needed to supply a population and absorb its waste |
| Biocapacity | what an area can supply and absorb; below the footprint means unsustainable |
| Carbon footprint | greenhouse gases produced, in tonnes of carbon dioxide equivalent |
| Green GDP | GDP minus the cost of environmental damage |
Last-minute check: answer, then tap to see.
A region's footprint crossed its biocapacity in 1990. What does the gap after 1990 show? An ecological deficit: it uses more than it can supply.
Give one limitation of the ecological footprint. e.g. it adds many things into one number, or cannot measure every impact.
How many planetary boundaries does the model have? Nine; about seven were judged crossed by 2025.
What are the two rings of the doughnut? The social foundation inside and the ecological ceiling outside.
What does Green GDP subtract from GDP? The cost of environmental damage.
To what extent is the ecological footprint the most useful indicator of a country's sustainability?
Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
Exam tips
- On a graph, quote figures with years and units.
- Always say which is bigger: the footprint or the biocapacity.
- For any model, learn two uses and two limitations, in the model's own words.
- In a [9], compare the indicator or model with at least one other before you conclude.