Food Production¶

Part of 4.7 Ecology.

Food production is an ecological problem as well as an economic one. Humans need reliable supplies of food, but the methods used to produce it can affect biodiversity, sustainability and resource use.

Learning Objectives¶

ID	Official specification wording	Main teaching sections
`4.7.5-lo-1`	4.7.5.1 Students should be able to describe some of the biological factors affecting levels of food security. 4.7.5.1 Food security is having enough food to feed a population. 4.7.5.1 Biological factors which are threatening food security include: 4.7.5.1 • the increasing birth rate has threatened food security in some countries 4.7.5.1 • changing diets in developed countries means scarce food resources are transported around the world 4.7.5.1 • new pests and pathogens that affect farming 4.7.5.1 • environmental changes that affect food production, such as widespread famine occurring in some countries if rains fail 4.7.5.1 • the cost of agricultural inputs 4.7.5.1 • conflicts that have arisen in some parts of the world which affect the availability of water or food. 4.7.5.1 Sustainable methods must be found to feed all people on Earth.	Food Security
`4.7.5-lo-2`	4.7.5.2 The efficiency of food production can be improved by restricting energy transfer from food animals to the environment. This can be done by limiting their movement and by controlling the temperature of their surroundings. 4.7.5.2 Some animals are fed high protein foods to increase growth.	Farming Techniques
`4.7.5-lo-3`	4.7.5.3 Fish stocks in the oceans are declining. It is important to maintain fish stocks at a level where breeding continues or certain species may disappear altogether in some areas. 4.7.5.3 Control of net size and the introduction of fishing quotas play important roles in conservation of fish stocks at a sustainable level.	Sustainable Fisheries
`4.7.5-lo-4`	4.7.5.4 Students should be able to describe and explain some possible biotechnical and agricultural solutions, including genetic modification, the demands of the growing human population. 4.7.5.4 Modern biotechnology techniques enable large quantities of microorganisms to be cultured for food. 4.7.5.4 The fungus Fusarium is useful for producing mycoprotein, a protein-rich food suitable for vegetarians. The fungus is grown on glucose syrup, in aerobic conditions, and the biomass is harvested and purified. 4.7.5.4 A genetically modified bacterium produces human insulin. When harvested and purified this is used to treat people with diabetes. 4.7.5.4 GM crops could provide more food or food with an improved nutritional value such as golden rice.	Biotechnology in Food Production

Food Security¶

Food security means having reliable access to enough safe and nutritious food to sustain a population. Several interacting factors can threaten it:

Population growth: as birth rates rise and healthcare improves, more people need feeding from the same or diminishing agricultural land.
Changing diets: increasing consumption of meat and fish worldwide requires more land and resources per calorie produced than plant-based diets.
New pests and pathogens: crop diseases and livestock infections can devastate yields; outbreaks can spread rapidly across global supply chains.
Environmental change: shifting rainfall patterns, more frequent droughts and flooding caused by climate change can cause repeated crop failures in vulnerable regions.
Conflict and distribution: war disrupts farming and transport; food can be plentiful globally yet still unavailable to populations isolated by conflict.
Sustainability pressures: growing crops for biofuel competes directly with food crop production for agricultural land.

Farming Techniques¶

Increasing Yield¶

Modern agriculture uses a range of techniques to increase how much food a given area of land can produce:

Fertilisers supply crops with mineral ions (especially nitrogen) that may be depleted from soil, boosting growth rates and yield.
Pesticides and insecticides reduce losses from insects and other invertebrates that damage crops, but must be carefully managed because they can harm non-target wildlife and accumulate in food chains.
Herbicides kill competing weeds, reducing competition for light, water and minerals.
Biological pest control uses living organisms — such as natural predators of pest species — rather than chemicals to keep pest populations down. It has longer-lasting effects and avoids chemical residues, but introduced organisms can themselves become ecological problems.
Hydroponics grows plants in mineral-rich water rather than soil, making it possible to cultivate crops in locations or conditions where soil quality is inadequate.
Glasshouses and polythene tunnels allow growers to control temperature, humidity, carbon dioxide concentration and light levels, extending growing seasons and maximising photosynthesis rates.
Selective breeding of crops and livestock over generations has produced varieties with faster growth, higher yield, disease resistance and other commercially valuable traits.
Gene technology can introduce specific genes into crop plants or livestock to confer precise traits such as pest resistance or improved nutritional content.

Intensive Farming¶

Intensive farming maximises output per unit of land or resource input. The guiding principle is to put in as much energy (inputs) as needed to achieve the highest possible yield.
Monoculture — growing only one crop species — simplifies management and mechanisation, but depletes specific soil nutrients and reduces habitat diversity for wildlife.
Intensive livestock rearing limits animal movement to reduce the energy they burn, and controls diet to maximise growth rate. These practices raise welfare concerns and are associated with increased antibiotic use, which contributes to antibiotic resistance.

Organic Farming¶

Organic farming avoids synthetic chemicals and instead uses natural fertilisers (manure, compost) and crop rotation to maintain soil health.
Crop rotation — changing which crop is grown in a field each season — prevents the build-up of soil-specific pests and replenishes nutrients depleted by previous crops.
Organic methods generally support greater biodiversity but typically produce lower yields per hectare than intensive methods.

Intensive food production can cause soil degradation, water pollution from fertiliser run-off (eutrophication), greenhouse gas emissions from livestock, and loss of natural habitats when land is cleared.
Economic pressures can make food expensive to produce or inaccessible to some populations even when global supply is adequate.

Sustainable Fisheries¶

Fish stocks worldwide have been seriously reduced by decades of overfishing. If fish are removed faster than populations can reproduce, stocks decline and may eventually collapse.
Fishing quotas (Total Allowable Catches, or TACs) set legal limits on how much of each species can be caught in a given period. Quotas are reviewed regularly and adjusted based on population surveys.
Net size regulations require larger mesh sizes so that immature fish can escape, allowing them to grow and reproduce before being caught.
Fish farming in tanks allows conditions — temperature, oxygen levels, pH and food supply — to be closely controlled, reducing disease and waste. Water is filtered to maintain quality.
Fish farming in cages in open water confines fish to reduce their energy expenditure (less swimming), controls their diet and protects them from predators, enabling faster growth. However, cages can concentrate parasites such as sea lice, which may require treatment with pesticides or biological control agents.

Biotechnology in Food Production¶

Mycoprotein is produced by growing the fungus Fusarium venenatum in industrial fermenters on glucose syrup. The resulting protein-rich biomass is harvested and processed into meat-substitute food products.
The process is efficient because fungi convert substrate to biomass at a much higher rate than animals, and the product is high in protein and fibre.
Genetic engineering has been used to produce crops with enhanced nutritional profiles (for example, golden rice with increased beta-carotene content) and resistance to specific pests or herbicides, though the use of such crops remains regulated and debated in many countries.

Common Confusions¶

Pesticides vs biological control: Pesticides provide immediate results but may harm non-target species and leave residues. Biological control is slower and carries the risk that the control organism becomes a pest itself, but avoids chemical contamination.
Intensive vs organic farming: Intensive farming maximises short-term yield but can have negative environmental and welfare consequences. Organic farming is more sustainable but typically produces less food per hectare — the trade-off between yield and sustainability is central to food security debates.
Fish farming vs wild fishery quotas: Both aim at sustainability but through different mechanisms. Quotas regulate catch from wild populations; farming creates controlled populations independent of wild stocks.

Key Terms¶

Food security: having reliable access to enough safe and nutritious food.
Selective breeding: choosing parents with desired traits so those traits appear more often in offspring.
Sustainable fishery: a fishery managed so that fish populations can continue to replace themselves.
Biotechnology: the use of living organisms or biological processes in industrial or food production.
Mycoprotein: food made from fungal biomass grown in industrial fermenters.
Monoculture: growing only one crop species across a large area.
Hydroponics: growing plants in mineral-enriched water rather than soil.
Biological pest control: using living organisms to reduce pest populations rather than chemical pesticides.
Crop rotation: the practice of growing different crops in a field in successive seasons to maintain soil health and reduce pest build-up.
Fishing quota: a legal limit on the quantity of fish that may be caught from a population in a given period.