Aquatic Ecosystems

3. wetlands on low, flat land with little water movement
5. marshes with slightly salty water
7. area where sunlight reaches only about 100 meters deep
8. lake with a large amount of nutrients and plant growth
10. flat, poorly drained wetlands dominated by woody plants and trees
11. coastal areas covered by salt water all or part of the time
16. marshes with saltier water and specialized plants and animals
19. areas covered by fresh water for part of the year
20. increase in nutrients in aquatic ecosystems causing plant and bacteria growth
24. microscopic animals that drift in the water
25. microscopic plants that drift in the water

1. depletion of fish populations by excessive harvesting
2. ponds, lakes, rivers, streams, and wetlands with low salinity
4. area where freshwater mixes with saltwater and deposits nutrient-rich mud
6. tropical wetlands dominated by mangrove trees that protect coastlines
9. water environments whose organisms are determined by salinity and other physical factors
10. maritime grass-dominated habitat that absorbs pollutants
12. shallow freshwater zone where light reaches the bottom
13. cold, oxygen-rich beginnings of a river
14. limestone ridges in warm saltwater containing diverse species
15. long ridge of sand parallel to shore that protects the mainland
17. deepest lake layer with little light where decay accumulates
18. organisms that swim independently of currents
21. bottom-dwelling organisms of aquatic ecosystems
22. microscopic organisms that float or drift in water
23. areas of land that are periodically underwater or have water-saturated soil