Food Production

• Monocultures - one plant species grown over a large

  area. Grown to increase food yield for growing human population.
• Advantages of Monoculture

  
  

  -Crop is grown to soil type and climate

  
  

  -Machinery used so labour costs are low and speeds up planting and harvesting

  
  

  -More than one harvest a year.

  
  

  -All have increased crop yield.
• Disadvantages of Monoculture

  
  

  -Large risk of disease as crops genetically identical.

  
  

  -Increased risk of pests and damage to crops due to the close

  planting.

  
  

  -Large scale use of fertilisers and potential for pollution problems.

  
  

  -Machinery compacts soil so less oxygen available to crops.

  Decrease crop yield

  
  

  -Hedgerows removed to increase field size but reduces

  biodiversity.
• In a monoculture, pesticides need to be used to control the pest population.

  
  

  These pests can lead to a reduction in crop yield.
• Most plants make proteins using nitrogen. But not from the air as they can’t absorb gaseous nitrogen. They absorb nitrogen through their roots as nitrates from the soil that they grow in.
• Nitrogen gas makes up 80% of the air
• Nitrogen is used by plants and animals to make protein
• Plants and animals cant make use of nitrogen gas directly
• Plants absorb nitrogen in the form of nitrates which is dissolved in soil

  water.
• Nitrates are used to produce amino acids which are then synthesised into plant proteins.
• Animals consume plants or other animals to obtain amino acids for protein synthesis.
• Soil nitrates can be increased by adding fertilisers.
• Eutrophication is excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life.
• Farmers could use natural fertilisers such as manure and compost to stop the

  risk of algal blooms.

  
  

  They could also use less fertilisers by using crop rotation.
• Pesticides are chemicals sprayed onto crops

  to reduce competition from other

  organisms. This can increase crop yield

  and food production.