Food supply
Growing more food
To grow more food, humans use:
- agricultural machinery to farm large areas quickly,
- chemical fertilisers to raise yields,
- insecticides to kill insect pests,
- herbicides to kill weeds that compete with crops,
- selective breeding to improve crops and livestock.
Practice
Which are used to increase food production? (Choose all that apply.)
Fertilisers, pesticides, machinery and selective breeding raise food output.
Practice
Herbicides are used to kill:
Herbicides kill weeds (insecticides kill insects), so the crop faces less competition.
Monoculture and intensive farming
- A monoculture (one crop over a large area) gives a big, easy harvest — but one pest or disease can destroy it all, and it lowers biodiversity.
- Intensive livestock farming (many animals in a small space) gives cheap meat — but raises animal-welfare and disease worries.
Practice
A disadvantage of a monoculture is that:
A single crop is easy to harvest but vulnerable to one pest/disease and reduces biodiversity.
You've got it
Key idea
- more food: machinery, fertilisers, insecticides, herbicides, selective breeding
- monoculture = big harvest but low biodiversity and high disease risk
- intensive livestock = cheap meat but welfare and disease concerns