Across
- 3. Protection of natural resources
- 5. Precipitation with high acidity
- 8. Removal of forests
- 10. Area draining into a river
- 12. Where river meets sea
- 17. Meeting needs without harming future
- 18. Simple aquatic plants
- 19. Rising of cold seawater
- 21. Study of ocean depth
- 22. Coastal tree or shrub
- 25. Contamination of environment
Down
- 1. Gas protecting from UV rays
- 2. Vent underwater geyser
- 4. Underground water source
- 6. Heat from Earth's interior
- 7. Small marine organisms
- 9. Temperature gradient in water
- 11. Replanting of trees
- 13. Trapping of heat by atmosphere
- 14. Deep ocean zone
- 15. Sunlit ocean layer
- 16. Enrichment of water by nutrients
- 20. Air pollution by smoke and fog
- 23. Salt concentration in water
- 24. Landform at river mouth