Across
- 1. group of microscopic organisms that are important to humans because of their chemical activities & as causes of disease
- 3. the rich upper layer of soil in which plants have most of their roots
- 5. a substance that is needed for healthy growth, development & functioning
- 6. the solid rock found under surface materials (as soil)
- 9. a layer of soil lying just under the topsoil
Down
- 2. a usable supply of something
- 4. naturally occurring substance (as ore, coal, salt or petroleum) obtained from the ground for human use
- 7. the dark rich part of the earth formed from decaying plant/animal material
- 8. particles of small size left as sediment from water