GCSE Revision

Increasing food supply

Ways to increase food supply

  • supplying water to crops, by channels, sprinklers or drips, so crops grow in dry areas or seasons.
  • growing plants without soil, with their roots in water containing nutrients.
  • growing plants with their roots hanging in air, sprayed with a nutrient mist.
  • The new green revolution: using new crop varieties and methods sustainably, to raise yields without harming the environment.
  • Biotechnology: (GM) changes crops' genes, for example to resist pests or drought.
  • simple, affordable tools that local people can use and repair, such as treadle pumps for irrigation.

Key terms

Thanet Earth

Thanet Earth, on the Isle of Thanet in Kent, is the UK's largest greenhouse complex: a .

  • It grows about 400 million tomatoes, 33 million cucumbers and 24 million peppers a year, according to local reporting in 2025.
  • Tomatoes are picked every day, all year round.
  • The crops grow hydroponically, without soil, in carefully controlled warmth and light.
  • Its own combined heat and power plants make electricity and heat for the greenhouses, and the carbon dioxide they produce is fed to the plants to help them grow.

It is an example of : high-tech farming run as a large business.

Key terms

Thanet Earth: advantages and disadvantages

Advantages:

  • grows salad crops in the UK all year, cutting imports and ;
  • high yields from a small area of land;
  • uses its waste heat and carbon dioxide, rather than letting them escape;
  • creates local jobs, in an area that needed them.

Disadvantages:

  • its combined heat and power plants burn natural gas, a fossil fuel;
  • the greenhouses were built on farmland, and change the look of the countryside;
  • the lights can be seen from far away at night;
  • a huge, costly scheme that small farmers couldn't afford.

Exam tip

Weigh both sides, and decide how far it improves the UK's food security.

Exam practice

Plan your own answer first, then open the model answers to see what each level looks like.

9 marks · about 9 minutes

To what extent does a large-scale agricultural development you have studied bring more advantages than disadvantages?

To what extent means: Weigh up how far something is true, with evidence on both sides, then give a clear judgement.

Link it

Use the facts from:

Level 1 (Basic)· 3/9 marks (band 1–3)
Thanet Earth grows lots of tomatoes in greenhouses. But it uses gas. I think it has more advantages.

Why this level: A named example, with simple points and an unsupported judgement. To reach Level 2: use facts to explain the advantages and disadvantages.

Level 2 (Clear)· 5/9 marks (band 4–6)
Thanet Earth, in Kent, is the UK's largest greenhouse complex. It grows about 400 million tomatoes a year hydroponically, all year round, which cuts imports and food miles, and creates local jobs. However, its combined heat and power plants burn natural gas, and it was built on farmland.

Why this level: Clear, accurate advantages and disadvantages. But they aren't weighed, and there's no judgement. To reach Level 3: compare them and conclude.

Level 3 (Detailed)· 8/9 marks (band 7–9)
Thanet Earth, on the Isle of Thanet in Kent, is the UK's largest greenhouse complex. It has clear advantages. It grows about 400 million tomatoes, 33 million cucumbers and 24 million peppers a year, picked all year round, so the UK imports less salad and food miles are cut. Crops grow hydroponically in controlled warmth and light, giving high yields from a small area. Its combined heat and power plants supply electricity and heat, and their carbon dioxide is fed to the plants, so less is wasted. It also creates local jobs. However, there are disadvantages. The power plants burn natural gas, a fossil fuel, so it still adds to climate change. The greenhouses were built on farmland, and their lights can be seen far away at night, causing light pollution. Overall, the advantages outweigh the disadvantages, because it greatly increases UK food supply efficiently, but it is not fully sustainable while it depends on natural gas.

Why this level: Detailed, accurate evidence on both sides, weighed to reach a qualified, supported judgement. This is Level 3.

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