Across
- 5. These break down dead plant material in soil.
- 7. This kind of resource does not run out.
- 8. This is combined with clay and sand to make soil.
- 9. Oil, gas and coal are ______ fuels.
Down
- 1. This word means the same as 'having a great variety of life'.
- 2. This creature is good for soil because it burrows tunnels that bring water and air to the roots of plants.
- 3. the common geographical name for silicon dioxide
- 4. a rock from which a metal is extracted
- 6. This type of resource is not made by humans.