Across
- 4. These are sources of energy that can be replenished thus can be used over and over again.
- 5. The type of rock formed when an existing rock is changed in form by heat and pressure.
- 6. One of the main types of pesticides.
- 7. A chemical used to control weeds
- 8. An ecological problem in which the concentration of toxins in living organisms become progressively higher at higher levels in a food chain.
- 9. The process by which nutrients are drained away from the soil by the action of rainwater.
Down
- 1. A process in which a living thing is used to remove toxic chemicals from a natural site.
- 2. The main mineral element which combines with glucose to form amino acids.
- 3. The process that leads to breakdown of rocks into smaller particles.
- 10. This type of soil is referred to as 'heavy' soil because it holds a high proportion of water.