Food: Global Supply & Management

Food is the most basic of human needs, yet hundreds of millions of people around the world do not have enough to eat. This lesson examines the global patterns of food supply and demand, the factors that cause food insecurity, and the large-scale strategies used to increase food production. Understanding these issues is essential for the AQA GCSE Geography exam.

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Global Food Supply Patterns

Food production is concentrated in certain regions of the world. The map of global food supply reveals stark inequalities.

Areas of Food Surplus

These countries produce more food than their populations need and often export the surplus:

Country/Region	Key Agricultural Products
USA	Corn, wheat, soybeans, beef, poultry
Brazil	Soybeans, coffee, sugar cane, beef
France	Wheat, wine, dairy, sugar beet
Australia	Wheat, beef, lamb, wine
Canada	Wheat, canola, barley
Argentina	Beef, soybeans, wheat

Areas of Food Deficit

These countries cannot produce enough food to meet their populations' needs:

• Sub-Saharan Africa — poor soils in some areas, unreliable rainfall, limited technology, conflict
• South Asia — high population density, vulnerability to monsoon failures and flooding
• Conflict zones — Yemen, Syria, South Sudan — where war has destroyed agricultural systems

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Factors Affecting Food Supply

Physical Factors

Factor	How It Affects Food Supply
Climate	Temperature and rainfall determine what crops can grow; droughts and floods destroy harvests
Soil	Fertile soils produce higher yields; poor or degraded soils limit production
Water	Reliable water sources enable irrigation; water scarcity limits farming
Relief	Steep terrain is difficult to farm; flat plains are ideal for large-scale agriculture
Natural hazards	Tropical storms, locust swarms, volcanic eruptions, and floods can devastate crops

Human Factors

Factor	How It Affects Food Supply
Technology	Mechanisation, irrigation, fertilisers, pesticides, and GM crops increase yields
Poverty	Poor farmers cannot afford seeds, tools, or fertiliser
Conflict	War displaces farmers, destroys infrastructure, and disrupts supply chains
Government policy	Subsidies, trade tariffs, and land reform policies shape agricultural output
Transport infrastructure	Poor roads and storage facilities mean food spoils before reaching markets
Land ownership	Unequal land distribution can leave small farmers with insufficient land

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The Impact of Climate Change on Food Supply

Climate change is already affecting food production and is expected to make food insecurity worse:

• Changing rainfall patterns — some regions are becoming drier (e.g. the Sahel), reducing crop yields
• Rising temperatures — crops have optimal temperature ranges; exceeding these reduces yields
• More extreme weather events — droughts, floods, and storms destroy harvests
• Shifting growing seasons — farmers must adapt to new planting and harvesting schedules
• Pest and disease spread — warmer temperatures allow pests to move into new areas
• Sea level rise — threatens low-lying agricultural land (e.g. Bangladesh, the Mekong Delta)

Exam Tip: Climate change is a common "command word" topic. If asked to "assess" or "evaluate" its impact on food supply, make sure you consider both negative effects (droughts, floods) and potential positives (longer growing seasons in some northern regions) — then reach a clear judgement.

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Strategies to Increase Food Supply

Irrigation

Irrigation is the artificial application of water to land for agriculture. It allows farming in areas that would otherwise be too dry.

• Types: flood irrigation, drip irrigation, sprinkler systems, centre-pivot irrigation
• Advantages: increases crop yields, allows year-round farming, enables agriculture in arid regions
• Disadvantages: expensive to install, can deplete groundwater, may cause salinisation (salt build-up in soil)

The Green Revolution

The Green Revolution (1960s–1980s) introduced high-yield variety (HYV) seeds, chemical fertilisers, pesticides, and mechanisation to developing countries, particularly in Asia.

Aspect	Detail
Origin	Led by scientist Norman Borlaug; began in Mexico, spread to India and Southeast Asia
Successes	India went from famine to food surplus in wheat and rice within two decades
Criticisms	Required expensive inputs (fertiliser, irrigation); benefited wealthy farmers more than poor ones; reduced crop biodiversity; caused environmental damage through pesticide and fertiliser overuse

Genetically Modified (GM) Crops

GM crops have been engineered to have desirable traits, such as resistance to pests, tolerance to drought, or higher nutritional content.

• Examples: Bt cotton (pest-resistant), Golden Rice (enriched with vitamin A), drought-tolerant maize
• Advantages: higher yields, reduced pesticide use, crops adapted to difficult conditions
• Disadvantages: concerns about health effects, corporate control of seed supply, loss of traditional varieties, ethical objections

Aeroponics and Hydroponics

• Hydroponics — growing plants in nutrient-rich water without soil
• Aeroponics — growing plants in air with nutrient mist sprayed onto roots
• Both allow food to be grown indoors, in urban areas, and in any climate
• They use significantly less water than traditional farming
• Used in vertical farms in cities like Singapore and Tokyo

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Large-Scale Agricultural Development: Almeria, Spain

Almeria in south-east Spain is one of the world's most intensive agricultural regions and is a key case study for the AQA specification.

Overview

Feature	Detail
Location	South-east Spain, on the Mediterranean coast
Area	Over 30,000 hectares of plastic greenhouses (the "Sea of Plastic")
Products	Tomatoes, peppers, cucumbers, courgettes, strawberries
Markets	Supplies much of Europe, especially the UK, Germany, and France
Technique	Intensive greenhouse farming using drip irrigation and hydroponics

Advantages

• Produces food year-round in a region that would otherwise be too arid for large-scale farming
• Generates billions of euros in revenue and provides employment for thousands
• Uses drip irrigation, which is more water-efficient than traditional flood irrigation
• The greenhouses reflect sunlight, potentially cooling the local area (the albedo effect)

Disadvantages

• Water depletion — the aquifers supplying Almeria are being over-abstracted; groundwater levels are falling
• Plastic waste — vast quantities of plastic sheeting generate enormous waste
• Labour exploitation — migrant workers (many from North Africa) often work in poor conditions for low pay
• Chemical runoff — pesticides and fertilisers contaminate local waterways
• Landscape impact — the "Sea of Plastic" has dramatically altered the natural landscape

Exam Tip: Almeria is a strong case study for questions about increasing food supply. Make sure you can explain both the economic benefits (jobs, revenue, food production) and the environmental and social costs (water depletion, pollution, worker exploitation).

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Trade and Food Supply

Global trade plays a crucial role in food distribution: