We can build more houses, more roads and more factories, but we cannot make more land. Every field we build on is a field that stops growing food. This page looks at how the world uses its land, who gets pushed aside when land use changes, and the three simple ways examiners expect you to sort farming systems.
📘 What you need to know
Land is a finite resource — roughly 70% of ice-free land is already used for farming and forestry.
Crops need soil that is fertile, land that is fairly flat, and a reliable water supply.
Steep or nutrient-poor land is usually grazed by animals instead of ploughed.
Population growth and urbanisation are cutting the amount of arable land available per person.
Land-use decisions hit marginalised groups hardest: indigenous peoples, women farmers, low-income communities.
Farming systems are classified by outputs, by reasons for farming, and by inputs.
All arable land is agricultural land, but not all agricultural land is arable.
Land is a finite resource
Start with the obvious point, because it drives everything else: the amount of land on Earth is fixed. About seven tenths of the ice-free land surface is already committed to agriculture and forestry, so there is not a huge untouched reserve waiting to be farmed.
Now add the population. More people means more mouths, so demand for food keeps rising. At the same time, cities keep spreading outwards, and urbanisation usually eats the flat, fertile land on the edges of towns — exactly the land that grows crops best. Put those two together and the result is a squeeze: the total amount of farmland is not growing much, but the number of people sharing it is. The land available per person falls.
The left bar is why there is no easy answer of “just farm more land”. The right bars are why efficiency matters so much in this topic.
Which land can actually grow crops?
Not every hectare is useful for crops. To plough and harvest reliably you need three things together: fertile soil, fairly flat ground, and enough water. Take away any one of them and arable farming becomes difficult.
Steep slopes. Rain runs downhill fast and carries topsoil with it, so erosion risk is high. Tractors and combine harvesters are also awkward or dangerous to use.
Nutrient-poor soils. Crops will not yield much unless you add large amounts of fertiliser, which costs money and causes pollution.
So what happens to that land? It usually gets grazed instead. Grass will grow on slopes and thin soils where wheat will not, and sheep can walk where a tractor cannot. That is why hilly areas such as Eryri (Snowdonia) in Wales and the Scottish Highlands are covered in sheep rather than cereal fields.
If a question describes steep, thin, wet upland and asks what farming happens there, the answer is almost always livestock grazing — and the reason is that the land fails the arable test, not that farmers prefer sheep.
Agricultural land vs arable land
These two terms get mixed up constantly, and examiners know it. Agricultural land is all land used for farming of any kind — crop fields, pasture, orchards, vineyards. Arable land is the narrower category: land actually used to grow crops, which needs the fertile-flat-watered combination above.
Draw this box-inside-a-box in your head whenever a question uses either term. It stops you writing “arable” when you mean all farmland.
Who loses out when land use changes
Land-use decisions are never just technical. Someone decides which land gets built on, which gets sold and which gets protected — and the people with the least power usually have the least say. Groups that tend to lose out include indigenous peoples, low-income communities, women farmers, and people in low-income countries. They often have weak or unwritten claims to land, so when a government or a company wants that land, they have little to fight with.
The consequence chain is worth learning as a chain: weak land rights → land taken for large projects → loss of livelihood → deeper inequality. That is the reasoning examiners want, not just a list of sad examples.
Example
What is happening
Who is affected
Amazon deforestation
Forest cleared for farms and cattle ranches
Indigenous groups such as the Yanomami lose land and biodiversity
Land grabs in Africa
Foreign investors buy up large blocks for industrial-scale farming
Local smallholders are displaced and their food security drops
Urban sprawl in China
Fast city growth swallows farmland on the urban edge
Rural communities lose access to nearby arable land
Land ownership in India
Caste barriers block many Dalit families from owning land
Families cannot build wealth or farm independently
Grazing lands in East Africa
Farming and tourism projects expand onto traditional pasture
Maasai herders in Kenya and Tanzania lose grazing routes
Value judgement alert. ESS wants you to notice that the same policy looks different depending on where you stand. A government may call a land deal “investment and development”; the family that farmed that land calls it displacement. Naming both viewpoints is worth marks.
Why farming looks different around the world
Two environmental factors do most of the explaining: soil and climate. Different biomes have very different soils, and soil decides what will grow without huge inputs.
Tropical soils are often nutrient-poor, because heavy rain and heat break down organic matter fast and wash nutrients away. Crops there usually need heavy fertilising — soya in Brazil is the standard example.
Temperate soils with moderate rainfall tend to be deeper and richer, so they support a wide mix of crops. The UK growing wheat and barley is the standard example.
So farmers are not choosing freely. They are choosing the best option their soil and climate allow, then adjusting with technology if they can afford it.
Three ways to classify a farming system
Any farm can be described in three different ways at once. Learn the three lenses and you can classify anything a question throws at you.
🧩 The three lenses
By output — what leaves the farm. Arable (crops), pastoral or livestock (animals), mixed (both), monoculture (one crop), diverse (many crops).
By reason — why they farm. Commercial (to sell), subsistence (to feed the household), sedentary (staying put), nomadic (moving with animals).
By input — what goes in. Intensive (lots of labour, money and technology per hectare) or extensive (little input per hectare); irrigated or rain-fed; soil-based or hydroponic; organic (no synthetic chemicals) or inorganic (synthetic fertilisers and pesticides).
Use all three lenses in an answer. Saying a farm is “intensive” alone is thin; saying it is intensive, commercial and pastoral shows you understand the classification.
What each system means for sustainability
Different systems trade off against each other. There is no single “best” farm, and saying so is what turns a 4-mark answer into a 6-mark one.
Type of sustainability
What tends to help
What tends to hurt
Economic
Diverse cropping spreads the risk, so one disease does not wipe out the income
Monoculture is profitable but fragile — one crop failure and the whole farm is in trouble
Social
Subsistence farming keeps food and work inside the local community
Large commercial farms create some jobs but can push small farmers off the land
Environmental
Organic and extensive systems protect soil health and biodiversity
Intensive systems degrade soil and pollute water through fertiliser and pesticide runoff
WORKED EXAMPLE
Distinguish between agricultural land and arable land. [2]
Both marks come from a clear contrast, not two separate definitionsAgricultural land = all land used for farming, including pasture, orchards and vineyards as well as crop fields.Arable land = only the land used to grow crops, which must be fertile, reasonably flat and have enough water.All arable land is agricultural, but not all agricultural land is arable“Distinguish” means put them side by side. Use the word “whereas” and you will not lose the comparison mark.
WORKED EXAMPLE
Explain why upland areas such as the Scottish Highlands are used for sheep grazing rather than crop production. [3]
Build it as a chain, one link per mark1. The slopes are steep and the soils are thin and nutrient-poor.2. So crop yields would be low, erosion risk is high, and machinery is difficult or unsafe to use.3. Grass still grows in these conditions and sheep can graze steep ground.Livestock is the only productive use the land conditions allow“Explain” = give reasons. Every sentence should contain a “because” or a “so”.
💡 Exam tip
Learn the 70% figure for ice-free land in farming and forestry. It is a quick, credible data point for any land-pressure question.
When asked about land use, always mention per capita availability, not just total area. That is where the population link earns marks.
Name a real place. “Sheep grazing in Eryri” beats “hilly areas” every time.
For any classification question, say which of the three lenses you are using so the examiner can follow you.
Use the fertile-flat-water test to justify why a piece of land is or is not suitable for crops.
In evaluation questions, split sustainability into economic, social and environmental and give one point on each.
⚠️ Common mix-up
Using arable and agricultural as if they mean the same thing. They do not, and it is a favourite trap.
Saying total farmland is falling. Usually the total is fairly flat — it is the amount per person that drops.
Confusing intensive with large. Intensive means high input per hectare; a small greenhouse can be very intensive.
Confusing extensive with bad. Extensive farming has low input per hectare and often has a lower environmental impact.
Confusing monoculture with commercial. Monoculture is about what is grown; commercial is about why.
Writing only about environmental impacts when a question says “sustainability”. Social and economic count too.
Up next: Traditional Versus Industrial Farming — nomadic herding, slash-and-burn, and the green revolution that changed food production forever.
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