Download Ocean notes part 2

Ocean notes part 2
Ocean Zones and Life
Marine Life is affected by:
Light
Pressure
Temperature
Salinity
Dissolved Oxygen
Factors change across different regions and depths
3 main zones due to depth and light:
Intertidal, Pelagic, and Benthic
Ocean life:
Classified by how they move and where they live
Plankton: tiny animals and algae that float in water and are carried by waves and currents
Nekton: free swimming animals that move throughout the water column
Benthos: organisms that live on the ocean floor
Intertidal zone:
 Shore that is seen between high and low tides
 Estuaries, tide pools, mangrove forests, salt marshes, rocky shores
 Estuaries: inlets or bays where freshwater from the river mixes with salt water from the oceans
 Salt Marsh: mud, animal, and plant nutrients. Many ocean animals hatch in salt marshes
before going to open ocean
 Mangrove forests: mangrove trees found in Florida that protect land by breaking waves and
winds from the ocean
 Rocky shores: rocky areas along the coast, where organisms live to adapt to the pounding
waves and sea spray
 Tide pools: water that stays in large pools in the rocks along the coast
Creature Adaptations:
 Must be able to tolerate changes in salinity, temperature, and exposed air.
 Endurance of pounding of waves
 Keep from being taken out to sea:
- Crabs and clams burrow in sand
- Seawood has holdfasts that keep them rooted
- Barnacles cement shells to rocks
Neritic zone:
 The area where the ocean slopes from the shoreline to the ocean floor
 Water depth up to 200 m
 Upwelling occurs
 Shallow water over continental shelf receives sunlight
 Temperatures and salinity stays constant
 More organisms’ homes than any other zone
Habitats:
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Coral reefs: found in shallow, tropical waters.
Formed from hard structures from coral to protect them
Atolls: ring shaped coral reef that surrounds a pool of water
Begins as a ring around an island
The island sinks but the reef keeps growing upward
Kelp forests: found in colder water near shores
Made of large brown algae
Abundant sea life:
Turtles, urchins, otters, fish, sea cucumber, abalones, sea stars, anenomies
Rapid growth-30 cm/day
Have air bladders that keep them upright
Photosynthetic (they do photosynthesis)
Pelagic zone:
 Open ocean
- Sunlight reaches only top 200 m
- Producers and consumers are at surface but there are few because less light and
fewer nutrients
- 3 zones by depth and light: surface, transition, and deep (abyssal)
Benthos zone:
 Ocean floor
- Dark and little oxygen
-Main energy source: detritus
-Organisms have adapted by becoming bioluminescent
Habitat:
 Abyss: the ocean floor
 High pressure, low temperature, and no light
 Organisms: worms, bacteria, sea urchins, and some fish
 Detritus : organic matter that falls from the surface (organisms eat)
 Also eat dead marine life that sinks to the bottom
 Hydrothermal vents: cracks in ocean’s crust that release mineral-rich water that has been
heated by the Eath’s interior
 In deep zone
 Water reaches 360 degrees Celsius
 Bacteria near vent uses chemicals from vent to make food
 Tube worms and clams eat baceria