Sustainable Living: 3M FuturewiseTown PlanIntroductionGo BackGo Next3M

Recycling nutrients

Plants are the creators!
Plants are vital for life on Earth. They are the producers at the start of food chains. They convert
sunlight into chemical energy at the start of most energy chains. They are also a key step in many
nutrient cycles. They take elements like carbon and oxygen from the air, hydrogen and nitrogen
from the soil – and they create complex compounds (carbohydrates, fats and proteins) on which we
all depend. When organisms excrete waste products or die, these compounds are returned
to the environment where they are broken down by microorganisms.

Microorganisms are the destroyers!
There are two types of organism responsible for the decay of organic materials.
They are grouped according to how they feed:

Detritivores – earthworms, maggots and woodlice
Detritivores feed on dead and decaying matter (detritus), breaking it up into smaller pieces. Smaller pieces have a bigger surface area, which speed up decay by other decomposers.

Saprophytes – bacteria and fungi
Saprophytes feed by extra-cellular digestion i.e. they secrete digestive enzymes onto the dead and decaying matter outside of their cells. The enzymes break down the materials and the nutrients are absorbed by the saprophyte.


 How many nutrient cycles do you know?

  Select an answer: 1 2 3