4.3 Aquatic food production systems

Significant ideas:

  • Aquatic systems provide a source of food production.
  • Unsustainable use of aquatic ecosystems can lead to environmental degradation and collapse of wild fisheries.
  • Aquaculture provides potential for increased food production.

Knowledge and understanding:

  1. Demand for aquatic food resources continues to increase as human population grows and diet changes.
  2. Photosynthesis by phytoplankton supports a highly diverse range of food webs.
  3. Aquatic (freshwater and marine) flora and fauna are harvested by humans.
  4. The highest rates of productivity are found near coastlines or in shallow seas, where upwellings and nutrient enrichment of surface waters occurs.
  5. Harvesting some species, such as seals and whales, can be controversial. Ethical issues arise over biorights, rights of indigenous cultures and international conservation legislation.
  6. Developments in fishing equipment and changes to fishing methods have lead to dwindling fish stocks and damage to habitats.
  7. Unsustainable exploitation of aquatic systems can be mitigated at a variety of levels (international, national, local and individual) through policy, legislation and changes in consumer behaviour.
  8. Aquaculture has grown to provide additional food resources and support economic development and is expected to continue to rise.
  9. Issues around aquaculture include: loss of habitats, pollution (with feed, antifouling agents, antibiotics and other medicines added to fish pens), spread of diseases and escaped species (some involving genetically modified organisms).

Applications and skills:

  • Discuss, with reference to a case study, the controversial harvesting of a named
    species.
  • Evaluate strategies that can be used to avoid unsustainable fishing.
  • Explain the potential value of aquaculture for providing food for future generations.
  • Discuss a case study that demonstrates the impact of aquaculture.

International-mindedness:

  • Successful management of marine and some freshwater fisheries requires partnership between different nations.

Theory of knowledge:

  • The Inuit people have an historical tradition of whaling—to what extent does our culture determine or shape our ethical judgments?

Connections:

  • Biodiversity and conservation (topic 3)
  • Terrestrial food production systems and food choices (5.2)
  • Human population carrying capacity (8.4)
  • Resource use in society (8.2)
  • Sustainability (1.4)