1. KEY CONCEPT Marine ecosystems are global. 70% of Earth’s surface is
water-covered. The oceans hold about 96.5% of the water.

2. The ocean can be divided into zones.
Simplest division:
Open Sea (Pelagic Zone) vs. Ocean Floor (Benthic)
Photic Zone -200 m (receives light) vs. Aphotic Zone (no sunlight)

3. intertidal zone—between low and high tide (Seashore)
Ocean zones can be determined by their distance from shoreline and water depths.
intertidal zone—between low and high tide (Seashore)
neritic zone— also
called coastal sea
from intertidal zone to continental shelf
bathyal zone—from neritic zone to base of continental shelf
abyssal zone –lies below 2000 m “The Abyss”
intertidal zone
neritic zone
bathyal zone
abyssal zone

4. Intertidal zone (Seashore)
Found between high and low tide line
Must tolerate changing conditions- salinity, temperature, moisture levels (tide pool, spray zone)
burrowers

5. Neritic zone (Coastal waters)
From edge of intertidal zone to edge of continental shelf
From shallow to deep (few cm to 200 m)
Majority of ocean life (coral reefs) Stable environment

6. Bathyal zone
Edge of neritic zone to the base of the continental shelf
From 200 m to 2000 m
High pressure, murky water

7. Abyssal zone
Below 2000 meters
Complete darkness
Deep-sea vent communities – chemosynthesis (bacteria)
Bioluminescence – lantern fish, angler fish

8. The neritic zone harbors 40X more biomass than any other zone.
Plankton make up most of the biomass.
Zooplankton
Phytoplankton (70% of oxygen)

9. Neritic or Coastal waters contain unique habitats.
Coral reefs are found in warm waters.
tropical climate zone (warm, clear water)
Usually between 25o N and 25o S Latitude
great amount of biomass (1000x more)
Coral- symbiotic relationship with algae (zooxanthellae)

10. Kelp forests are found in cold, nutrient-rich waters.
100 feet tall ( grow a foot a day)
large communities of seaweed
great amount of biomass
Harvested for foods/cosmetics