3.5 FOOD PRODUCTION

To help increase crop yield we can use : ● Fertilisers ● Pesticides

Genetically modified (GM) crops can be used to reduce the use of fertilisers.

Pesticides sprayed onto crops can accumulate in the bodies of organisms over time.

Nitrate

pesticides can increase crop yield, by killing unwanted animals and plants that would reduce crop yield.

Fertilisers provide chemicals such as nitrates which increase crop yield

Animals consume plants or other animals to obtain amino acids for protein synthesis

Unwanted nitrates increase alagal population Algal blooms reduce light levels, killing aquatic plants These dead plants become food for bacteria which increase greatly in number. The bacteria use up large quantities of oxygen, reducing the oxygen availability for other organisms.

biological control and genetically modified (GM)

Fertilisers provide chemicals such as nitrates which increase crop yield

Biological control is using the natural predator of the pest to reduce numbers