IB Environmental Systems and Societies/Food Resources

Food Resources


Assessment Statements

  • 3.5.1 Outline the issues involved in the imbalance in global food supply
  • 3.5.2 Compare and contrast the efficiency of terrestrial and aquatic food production systems
  • 3.5.3 Compare and contrast the inputs and outputs of materials and energy (energy efficiency), and system characteristics, and evaluate the relative environmental impacts for two named food production systems
  • 3.5.4 Discuss the links that exist between social systems and food production systems

Food Production

  • imbalance in food supply
  • MEDCs are over-consuming
  • LEDCs suffer from under-nourishment (food intake not containing enough energy) and malnutrition (food intake lacking essential nutrients)
  • food prices play a crucial role (10% increase in food prices can lead to 40 million more people in food poverty)
  • Import tariffs: (imposed by MEDCs) make import of food more expensive
  • Export subsidies: subsidies provided by MEDCs to make farm products from LEDCs uncompetitive


  • 90% of energy is lost through each trophic level
  • terrestrial production systems are more efficient than aquatic food production systems
  • terrestrial:
  • most food is harvested from relatively low trophic levels (more energy)
  • aquatic:
  • most food is harvested from higher trophic levels (mostly because of taste preferences) (less energy)
  • energy conversion is more efficient (producer to consumer), but initial fixing of available solar energy tend to be less efficient due to absorption and reflection of light by water

Food Production Systems: Terrestrial

  • Commercial farming: farming for profit; often a single crop
  • Subsistence Farming: produce only enough to feed family, with none to sell for profit
  • both commercial farming and subsistence farming can be intensive or extensive
  • Intensive farms
  • take up small area of land
  • very high output (through large inputs of capital and labor)
  • Extensive farms
  • large in comparison to the money and labor put into them
  • efficiency of system can be calculated by comparing outputs to inputs
  • outputs: marketable product
  • inputs: fuel, labor, transport, fertilizer, dealing with waste products
  • Shifting Cultivation
Also known as "slash and burn" agriculture
Land is cleared by cutting down small areas of forest and setting fire to them. The ash fertilizes the soil and crops can be grown. When the minerals in the soil is depleted, the farmer moves to a new area. The old area can be returned to once the fertility has recovered.
This is an example of extensive subsistence farming.
  • Rice agriculture (South-East Asia)
Rice can be grown in dry-fields, but padi field (wet rice) (heavy clay soils) agriculture has become the dominant form of growing rice in South-East Asia.
High population densities lead to high demand for food, especially rice, which is a staple part of the diet and a central part of Asian culture.
This is an example of intensive subsistence farming. (high level input, low level technology)
  • Agribusiness
Agribusiness is when regulation of food production is not to satisfy the community's needs but is to ensure profitable return for capital investment (producing food for people's needs-->producing food for commercial profit)
Distinguishing methods of agribusiness:
  1. large-scale monoculture: huge fields where only one crop is grown
  2. intensive use of fertilizers and pesticides
  3. mechanized ploughing and harvesting
  4. food production geared to mass markets including export
These large farms decreased demand for labor, which led to local migration of people into towns and cities as they sought new work.