Food Production and the Environment

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Food Production and the Environment

• The Carbon Cycle

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Carbon dioxide in the air
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Carbon dioxide in the air
Green plants use carbon dioxide to make their food
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Carbon dioxide in the air
Green plants use carbon dioxide to make their food
Green plants are eaten by animals
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Carbon dioxide in the air
respiration
Green plants use carbon dioxide to make their food
Green plants are eaten by animals
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carbon dioxide in the air
respiration
green plants use carbon dioxide to make their food
green plants are eaten by animals
dead remains of plants and animals
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carbon dioxide in the air
respiration
green plants use carbon dioxide to make their food
green plants are eaten by animals
dead remains of plants and animals
decay by fungi and bacteria
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Decay

• Fungi and bacteria are responsible for the decay
  of dead organisms.

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Decay

• In order to be able to carry out decay, fungi and
  bacteria need
• Oxygen
• Moisture
• The correct temperature

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The Nitrogen Cycle
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nitrogen in the air
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nitrogen in the air
fertilizers
fertilizers
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nitrogen in the air
fertilizers
fertilizers
waste substances e.g. faeces
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nitrogen in the air
lightning
fertilizers
fertilizers
waste substances e.g. faeces
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nitrogen in the air
lightning
fertilizers
fertilizers
waste substances e.g. faeces
Nitrogen-fixing bacteria in the soil
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nitrogen in the air
lightning
fertilizers
fertilizers
waste substances e.g. faeces
Nitrogen-fixing bacteria in the soil
Nitrogen-fixing bacteria in the root nodules of
clover
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nitrogen in the air
lightning
fertilizers
fertilizers
waste substances e.g. faeces
Nitrogen-fixing bacteria in the soil
Nitrogen-fixing bacteria in the root nodules of
clover
dead remains of plants and animals
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nitrogen in the air
lightning
fertilizers
fertilizers
waste substances e.g. faeces
Nitrogen-fixing bacteria in the soil
Nitrogen-fixing bacteria in the root nodules of
clover
dead remains of plants and animals
nitrates in the soil
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lightning
fertilizers
fertilizers
waste substances e.g. faeces
Nitrogen-fixing bacteria in the soil
Nitrogen-fixing bacteria in the root nodules of
clover
dead remains of plants and animals
nitrates in the soil
denitrifying bacteria in the soil break down
nitrates
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The nitrogen cycle

• Living things need nitrogen to make protein.
• They can not use the nitrogen in the air
• The nitrogen in the air must be changed to
  nitrates before plants can use it.

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The nitrogen cycle

• Animals get their nitrogen by eating plants.

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The nitrogen cycle

• The roots of some plants (e.g. clover, pea
  beans) have swellings called root nodules on
  them.
• Nitrogen-fixing bacteria living in these nodules
  change nitrogen in the air into nitrates.

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The nitrogen cycle

• The nitrogen-fixing bacteria are essential to
  maintain the fertility of the soil.
• Without them food yields would rapidly fall.