1. Aquatic Life Zones: 2 major categories
Marine (saltwater) Or
Freshwater
Types of organisms determined by:
Salinity
Temperature
Sunlight availability
D.O. (dissolved oxygen)
Nutrient availability

2. Major types of Organisms
1. Plankton: small free-floating
organisms
2. Phytoplankton: plant-like
Photosynthetic
Algae, cyanobacteria

3. 3. Zooplankton: animal-like
Heterotrophic
Protozoans
Larvae
Copopods, cnidarians, krill…etc.
4. Ultraplankton: TINY (less than 2 micrometers)
includes bacteria

4. 5. Benthos (benthic organisms): bottom dwellers – anchor to one spot, burrow, or walk along bottom

5. 6. Nekton: active swimmers – don’t follow currents

6. 7. Baleen whales: filter feeders Plates (baleen) hang from upper jaw – filter plankton from water includes: 8. humpbacks and 9. blue whales

7. 10. Toothed whales: teeth used to bite and chew food includes: 11
10. Toothed whales: teeth used to bite and chew food includes: 11. orca (killer whale) and 12. sperm whale

8. 13. A Marine Food Chain (example)

9. Marine Lifezones

10. 13. Coastal/Neritic High tide to Continental shelf
(Ample sunlight) so: high 14.NPP and D.O.
90% of all marine species

12. 15. Coral reefs (in the coastal zone): MOST biodiverse areas of all aquatic life zones
“The Aquatic Rainforest”
Hundreds of thousands of coral polyps excrete CaCO3 skeletons

13. Grow slowly, disrupted easily:
Biggest threats: sediment run-off
Bleaching (even from 1 degree temp increase)

14. Removal (aquariums/jewelry)
Pollution
Damage (tourists, anchors, natural disasters)
Overfishing
Cyanide/dynamite “fishing”
1 m2 of reef killed for every fish caught

15. 16. Intertidal zone: shoreline between low and high tide
Tides caused by gravitational pull of moon
Organisms adapted to HARSH conditions (wet/dry, warm/cold, salty/not-so-much)

16. 17. Barrier Islands: islands separated from the mainland by a shallow sound, bay, or lagoon

17. Constantly shifting beaches due to erosion
Can be helped with a jetty

18. Dunes – backbone that provides stability
Plants hold sand in place
Protect from natural disasters

19. 19. Coastal wetlands: inlets, bays, sounds, Mangrove forest swamps

20. 20. Estuary: where freshwater meets saltwater (mouth of a river)

22. 22. Pelagic or Open Ocean

23. Side-note: Low NPP per unit area, but adds up!!
23. Epipelagic or photic zone: TOP
Sunlight layer: warmer water, phytoplankton = 24. photosynthesis: HIGH D.O. (dissolved -oxygen); big fish and mammals
Side-note: Low NPP per unit area, but adds up!!

24. 25. mesopelagic and bathyalpelagic zones: MIDDLE Dimly lit/dark – twilight/midnight regions
little/no producers (little 26. D.O.), - zooplankton, smaller fish, squid

25. 27. Abyssal or Abyssopelagic zone: bottom (The Deep Dark Abyss!)
Dark, cold, varying D.O. , nutrients on floor
Organisms adapted to HIGH pressure, COLD temps, NO light!
Bioluminescence adaptation
Chemosynthetic bacteria at hydrothermal vents

29. 28. Equation:
6CO2 + 6H2O + 3H2S C6H12O6 + sulfur compounds

32. 29. Hadel Zone…
Or Hadelpelagic zone… - Deepest trenches in ocean Side-notes:
Average ocean depth 2.3 miles or approx 12,000 ft
Deepest hadel zone point: 30. Challenger Deep (part of Mariana Trench) = approx 36,000 feet or 6.8 miles deep!
Approx 16,000 psi of pressure… compared to about 14 psi at surface