1. Aquatic Ecosystems
4.5

2. Water depth –
- Photic Zone – sunlight gets through; photosynthesis can occur here
- Aphotic Zone – dark (no light); no photosynthesis

3. Freshwater Ecosystems
3% of Earth’s surface water
3 categories:
- Rivers and Streams
- Lakes and Ponds
- Freshwater Wetlands (3 types)
- freshwater bogs, marshes, and swamps

4. Estuaries = wetland where river meets the sea (fresh and salt water)
Support a large amount of biomass
Important area for spawning and nursery of many fish and shellfish

5. Marine Ecosystems = ocean
Divided into zones based on depth and distance from shore

6. 3 zones
- intertidal zone (in water at high tide, in air at low tide)
- coastal ocean (low tide mark to outer edge of continental shelf)
- open ocean (edge of continental shelf out) (90% of world’s ocean area)