Across
- 6. A major regional group of distinctive plant and animal communities
- 10. Excessive richness of nutrients in a lake or other body of water
- 11. The process by which fertile land becomes desert
- 13. The biological process of breaking down organic matter
- 14. The protection of natural resources and environment
- 15. Avoidance of the depletion of natural resources
- 16. The process by which plants use sunlight to synthesize nutrients
- 18. The increase of acidity in a particular environment
- 19. The introduction of harmful materials into the environment
Down
- 1. The gradual accumulation of substances in an organism
- 2. The action of clearing a wide area of trees
- 3. The process of gaseous exchange in living organisms
- 4. A biological community of interacting organisms and their physical environment
- 5. The atmospheric trapping of the sun's warmth
- 6. The variety of plant and animal life in a particular habitat
- 7. The increasing concentration of a substance in organisms
- 8. The process of making an area more urban
- 9. The protective layer shielding the earth from ultraviolet radiation
- 12. The study of the relationships between organisms and their environment
- 17. The natural home or environment of an animal or plant