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Soil
Most of the dry land on the earth is covered with soil.
Plants grow in soil.
Soil is made when rocks break and crumble.
Rocks are broken by earthquakes and volcanoes. Rain, frost, sun, wind, water and ice all help to break up the rocks. It takes thousands and thousands of years for the rocks to turn into soil. This is called weathering.
When plants die they rot in the soil. Rotting plants change into humus. Humus makes the soil healthy for new plants. Humus and plants hold the soil together.
The soil is the home for millions of animals. These animals make burrows and tunnels under the ground. Burrowing and crawling through the soil, the animals turn it over and mix it up. Air for the animals to breathe gets into the soil. The roots of plants need the air too. Rainwater runs into the soil and waters the plants.
Before a farmer plants crops, the soil is ploughed. Ploughing beaks up the soil and makes spaces for air and water which the plants will need as they grow.
Erosion: wearing away the soil
Erosion is the wearing away of soil. Erosion happens when there is too much rain and there is a flood. The flood waters wash away the soil. Winds also blow the soil away. This is erosion too.
Erosion also happens when too many trees are cut down. The trees were holding the soil together. When they are gone, the winds and water 
blow and wash the soil away. To stop erosion, people plant trees, bushes and grasses to hold the soil together.
planting trees helps to stop soil eosion
Tree planting pic.© photos.com
You can read more about erosion on kidcyber here
Go to the next page to read about types of soil 
Acknowledge this page in your bibliography like this:
Thomas, Ron. & Sydenham, Shirley. Soil [Online] www.kidcyber.com.au (2011)
January 2011 text copyright © kidcyber [2011]