Food securitySpec 9.11B
Food security means having enough food to feed a population. Several biological factors make it harder to achieve.
- Increasing human population: more people need more food, which puts pressure on land and resources.
- Increasing animal farming and increased meat and fish consumption: energy is lost at each trophic level, so producing meat and fish needs much more land and crops than eating plants directly. Wild fish stocks can be overfished.
- New pests and pathogens: these can spread quickly and destroy crops and farm animals, reducing the amount of food produced.
- Environmental change caused by human activity: for example climate change, pollution and loss of habitats can reduce crop yields or the area of land that can be farmed.
- Sustainability issues: for example using land to grow crops for biofuels instead of food, and the cost of agricultural inputs such as fertilisers, pesticides, fuel and animal feed, which can make farming unaffordable.
Quick check
Name the three human interactions you must be able to explain for this topic.
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Fish farming, introduction of non-indigenous species, eutrophication.
Why do fish die in eutrophication?
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Bacteria feeding on dead plants and algae use up the oxygen in the water.
Give two benefits of reforestation.
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Any two of: restores habitats, absorbs carbon dioxide, reduces soil erosion.
What is meant by a non-indigenous species?
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A species introduced to an area where it does not naturally live.