The big idea: A food system is the whole chain that gets food from field to plate — production, processing, distribution and consumption — plus the inputs (energy, water, labour, seeds, fertiliser) and outputs (food, waste, emissions) at each stage.
Food production is the first stage: how farms turn land, energy and labour into food. Systems differ in how intensive they are, how much energy they use, and how efficient they are.
Key terms for food production
- Food system — production → processing → distribution → consumption, with inputs and outputs at each stage.
- Inputs — what goes into farming: energy (fuel, electricity), water, labour, seeds, fertiliser, machinery.
- Outputs — what comes out: food (the yield), plus waste and emissions.
- Intensive farming — high inputs per hectare for a high yield (e.g. greenhouses, feedlots).
- Extensive farming — low inputs spread over a large area (e.g. cattle ranching).
- Energy efficiency — the output ÷ input ratio: how much food energy you get for the energy you put in.
Intensive isn't the same as efficient: An intensive system uses lots of inputs per hectare — but that does not make it energy-efficient.
Intensive beef or heated greenhouses put in far more energy than they return (a low output ÷ input ratio). A low-input root crop like cassava returns several times the energy it uses.
How this is tested: Paper 1 Option F opens with a data-response on a food figure — often an energy input/output graph for different farm products, a food-waste-by-region chart, or a Venn diagram of food-production types.
You Identify, State or Estimate a value: the product with the lowest output, the highest efficiency (best output ÷ input), or which categories a method falls into. Read the correct row or axis carefully.
| Farm product | Energy input | Energy output | Output ÷ input (efficiency) |
|---|---|---|---|
| Cassava (low-input root crop) | 5 | 60 | 12.0 — very efficient |
| Rice (irrigated) | 15 | 75 | 5.0 |
| Wheat (mechanized) | 20 | 70 | 3.5 |
| Greenhouse lettuce | 30 | 12 | 0.4 — lowest output |
| Beef (intensive) | 40 | 8 | 0.2 — least efficient |
Efficiency = output divided by input: The product with the lowest output is the one with the smallest output column — not the smallest input.
The most efficient product has the highest output ÷ input ratio (the last column) — cassava returns 12 units of food energy for every 1 it uses, while intensive beef returns only 0.2.
Study smarter, not longer
Most students waste 40% of study time on topics they already know. Our AI tracks your progress and optimizes every minute.
Try Smart Study Free7-day free trial • No card required
Food production changes over time as farms mechanize, as technology spreads, and as physical conditions shift. Mechanization raises yields but changes the energy mix; physical factors like drought, flooding or pests can force farmers to change what they grow or how.
| Change | Effect on energy input |
|---|---|
| Tractors and combines replace hand tools | More fossil-fuel (diesel) energy used; much less human/animal labour energy |
| Synthetic fertiliser and pesticides | Large hidden energy input to make and apply them |
| Irrigation pumps and machinery | More electricity / fuel to move and lift water |
| Higher yields per worker | Total energy input rises, but output per worker rises faster |
Physical factors that change food production
- Climate change — warming and shifting rainfall move where crops will grow; some areas gain a longer season, others lose viable land.
- Drought — the Sahel in Africa has suffered repeated droughts that cut yields and force a switch to drought-tolerant crops like millet and sorghum.
- Flooding — destroys crops and waterlogs soil, pushing farmers to flood-tolerant rice varieties or raised fields.
- Pests and disease — new pests (e.g. fall armyworm spreading across Africa) can wipe out a harvest and change which crops are planted.
- Soil change — erosion and salinisation from over-irrigation lower fertility and shrink what can be grown.
Always give the mechanism: Don't just name a factor — explain how it changes production. Drought → less water → lower yields → farmers switch to drought-tolerant millet. For an Explain [3], name the physical factor, then develop the chain with a worked example.
Vertical and indoor farming — the newest method: Vertical farms stack crops indoors under LED light with controlled climate and no soil (hydroponics). They use land efficiently in cities, but their disadvantages matter: a high energy demand for lighting and climate control, expensive set-up, a limited crop range (leafy greens, herbs) and heavy technology dependence.
In a Venn diagram of food-production types, a city skyscraper farm sits inside all three categories — urban, indoor and vertical — while a rooftop greenhouse is only urban and indoor.
How new farming methods spread (diffusion): Diffusion is how a new method, seed or technology spreads from where it started to other farmers and regions. The Green Revolution in India (from the 1960s) spread high-yield wheat and rice varieties, fertiliser and irrigation — hugely raising output, but unevenly: better-off farmers near roads and credit adopted fast, while poorer, remote farmers were left behind.
Whether an innovation spreads quickly depends on physical, economic, social and political geographic factors.
What controls how fast an innovation spreads
- Physical — a new seed only spreads where the climate, water and soil suit it (high-yield rice needs reliable irrigation).
- Economic — cost, credit and market access: farmers near roads and banks can afford fertiliser and machinery; remote, poor farmers cannot.
- Social — education, information and trust: literate, well-connected farmers hear about and accept new methods faster.
- Political — government support: subsidies, extension services and stable land rights speed adoption; their absence slows it.
How this is tested — the [10] Examine essay: Paper 1 Option F ends with a 10-mark Examine essay, marked on markbands. A recurring version asks how geographic factors (physical, economic, social, political) speed up or slow the diffusion and adoption of new farming methods.
Top band needs: accurate terms, two or more developed factors with a named example (the Green Revolution), a weighing of their relative importance / interactions, and a clear conclusion.