Across
- 3. the wearing down of rock by disintegration
- 5. sewage that has been treated in a septic tank or sewage treatment plant
- 6. process of creating new lands from oceans, river beds and seas.
- 7. the process of doing so by adding a loose layer of shredded plant material on top of the soil.
Down
- 1. the supply of water to land or crops to help growth
- 2. the planting of more trees
- 4. the organic component of soil.