Life in the Soil

The top layers of the soil are full of living organisms. Most of them are microscopic organisms, also called microbes.

Johnny's Fact File No.42 A square meter of grassland soil may contain over half a kilogramme of microbes.

Most of these organisms are fungi and bacteria that eat dead leaves which have fallen to the ground. This is how the leaves decompose.

When something decomposes, it means that it is broken down into small particles.

Some soil organisms, such as springtails and mites, are big enough to be seen by the naked eye as little dots. They can be observed in more detail by using a binocular microscope.

Johnny's Fact File No.43 The biggest earthworms in the world are found in Australia. They may grow to nearly four meters long.

These, too, are mostly decomposers; so are the large earthworms which can be seen even without a hand lens. All of these organisms are relatively small but play a very important role in making soil.

• Environmental Factors Appropriate for Life
• Soil
• What is soil made of?
• Associated Practical Work
• Questions relating to this chapter
• Top of Page

© Paul Billiet, Shirley Burchill, Alan Damon and Deborah James 2008