What you'll learn
The world's growing population needs more food, but producing it must not damage the environment or use up resources for the future — this is the challenge of sustainable food production. For AQA GCSE Biology you need to understand what food security is, the factors that threaten it, how food production can be made more sustainable, and issues such as fishing, farming and biotechnology. This guide covers food security and its threats, sustainable fishing, efficient farming, and biotechnology in food production. By the end you should be able to explain the threats to food security and evaluate ways of producing food sustainably.
Key terms and definitions
Food security — Having enough food to feed a population.
Sustainable — Able to continue over a long time without harming the environment or future supplies.
Biodiversity — The variety of living organisms in an area.
Fish stock — The population of fish available to be caught.
Sustainable fishing — Fishing at a level that allows fish populations to recover.
Biotechnology — Using living organisms or their processes to make useful products.
Mycoprotein — A protein food made from a fungus, produced by fermentation.
Genetic engineering — Changing the genes of an organism to give it desired characteristics.
Core concepts
Food security and its threats
Food security means having enough food to feed a population. Many factors threaten food security around the world, including:
- Increasing population — more people need more food.
- Changing diets — as people become wealthier, they eat more meat and other resource-intensive foods.
- New pests and pathogens — which can destroy crops and livestock.
- Environmental changes — such as changing rainfall and temperature affecting farming.
- Cost of farming inputs, and conflicts affecting food supply.
Meeting food security sustainably means producing enough food without damaging the environment or exhausting resources for the future.
Efficiency and sustainable farming
Because energy and biomass are lost between trophic levels, food production can be made more efficient. Producing crops to eat directly is more efficient than feeding crops to animals, because each extra trophic level loses about 90% of the biomass. Farming animals can be made more efficient by limiting their movement and controlling their temperature, so more of their food becomes biomass — but this raises animal welfare concerns. Sustainable farming aims to produce enough food while protecting the soil, biodiversity and environment for the future.
Sustainable fishing
Fish are an important food source, but overfishing has reduced many fish stocks to dangerously low levels. If too many fish are caught, populations cannot reproduce fast enough to recover, and the stock can collapse. Sustainable fishing protects fish stocks so they can continue to be a food source, using methods such as:
- Fishing quotas — limits on the amount and type of fish that can be caught.
- Controlling net mesh size — larger holes let young fish escape to breed, so only mature fish are caught.
These methods allow fish populations to recover and be maintained, so fishing can continue in the long term.
Biotechnology and mycoprotein
Biotechnology uses living organisms to produce food. One example is mycoprotein, a protein-rich food suitable for vegetarians, produced from a fungus (Fusarium). The fungus is grown on sugar (glucose syrup) in large vessels called fermenters, in aerobic conditions, and the mycoprotein is harvested and purified. This provides a source of protein without needing to raise animals, using less land and resources.
Genetic engineering in food production
Genetic engineering can be used to modify crops to improve food production — for example, making crops resistant to pests or diseases, or improving their yield or nutritional value. A well-known example is engineering crops to produce a particular vitamin. Genetically modified (GM) crops can increase food production and reduce the need for pesticides, but there are concerns about their effects on health, on wild populations and on biodiversity, and about who controls the technology. This makes GM crops a common "evaluate" topic.
Balancing production and sustainability
The overall challenge is to produce enough food while keeping production sustainable — protecting the environment, biodiversity and resources for future generations. Many approaches involve trade-offs: efficient animal farming raises welfare concerns, GM crops raise safety and environmental concerns, and intensive farming can harm biodiversity. Good answers weigh the benefits of greater food production against these concerns.
Biodiversity and sustainable farming
Protecting biodiversity — the variety of living organisms — is an important part of sustainable food production. Intensive farming can reduce biodiversity, for example by clearing hedgerows, using large amounts of pesticides that harm insects, or growing single crops (monoculture) over large areas. Losing biodiversity can be harmful because it reduces the natural pest control, pollination and healthy soil that farming depends on. Sustainable approaches try to maintain biodiversity, for example by leaving field margins, reducing pesticide use, and rotating crops. Recognising that food production depends on a healthy environment, and that protecting biodiversity supports long-term food security, shows an understanding of what "sustainable" really means.
The role of biotechnology in food security
Biotechnology offers several ways to help meet food security sustainably. As well as producing mycoprotein, microorganisms are used in food production such as making yoghurt and bread. Genetic engineering can produce crops that are resistant to pests, drought or disease, or that have improved nutritional value, which can increase yields on the same amount of land. These technologies could help feed a growing population without clearing more land, which would protect the environment. However, they bring concerns about safety, biodiversity and who controls the technology. Being able to discuss how biotechnology might improve food security, while weighing the concerns, is exactly the kind of balanced answer the exam rewards.
Worked examples
Example 1: A threat to food security
Explain how a growing population threatens food security. A larger population needs more food, so the same amount of food has to feed more people. Unless food production increases sustainably, there may not be enough food for everyone, threatening food security.
Example 2: Sustainable fishing methods
Explain how controlling net mesh size helps fish stocks recover. Nets with a larger mesh size let young, immature fish escape, so they are not caught and can grow and reproduce. This allows the fish population to recover and be maintained, making fishing sustainable.
Example 3: Producing mycoprotein
Describe how mycoprotein is produced. Mycoprotein is made from a fungus grown on glucose syrup in a fermenter under aerobic conditions. The fungus reproduces rapidly, and the mycoprotein is then harvested and purified to make a protein-rich food.
Example 4: Evaluating GM crops
Give one benefit and one concern of using genetically modified crops. A benefit is that GM crops can be made resistant to pests or diseases, increasing yields and reducing the need for pesticides. A concern is the possible effects on health, wild species or biodiversity, which are not fully known.
Common mistakes and how to avoid them
A common error is thinking sustainable food production just means producing more food. It means producing enough food without harming the environment or using up resources for the future. Always include the sustainability aspect.
Students often forget why overfishing is a problem. If too many fish are caught, populations cannot reproduce fast enough to recover, so the stock declines — sustainable methods let fish breed before being caught.
Another mistake is describing mycoprotein production incompletely. Remember it is made from a fungus, grown in a fermenter on sugar in aerobic conditions, then harvested and purified.
When discussing efficient animal farming, do not give only the benefits. Restricting movement raises animal welfare concerns, and good answers weigh both sides.
Finally, for GM crops, give a balanced view — benefits such as pest resistance and higher yield, but concerns about health, biodiversity and control. Evaluation questions expect both.
Exam technique for "Sustainable food production"
Be ready to explain the threats to food security (population, diet, pests, environment) and to link efficient food production to the loss of biomass between trophic levels.
For fishing, explain how quotas and mesh size protect stocks by allowing fish to breed and recover. For biotechnology, describe mycoprotein production and the use of genetic engineering, and be ready to evaluate GM crops.
Most questions here are "explain" or "evaluate", so give balanced answers that weigh greater food production against environmental, welfare and safety concerns. Use precise terms — food security, sustainable, fish stock, mycoprotein, genetic engineering — throughout.
Quick revision summary
- Food security is having enough food; threats include a growing population, changing diets, pests and pathogens, and environmental change.
- Producing crops to eat directly is more efficient than feeding them to animals; efficient animal farming raises welfare concerns.
- Overfishing reduces fish stocks; sustainable fishing uses quotas and net mesh size so fish can breed and recover.
- Mycoprotein is made from a fungus grown in a fermenter on sugar in aerobic conditions.
- Genetic engineering can make crops pest-resistant or higher-yielding, but raises health, biodiversity and control concerns.
- Sustainable food production means producing enough food without harming the environment or future resources — weigh the trade-offs.