1. The Marine Biome Cycle carbon dioxide and oxygen on Earth
Modifies temperatures changes
Home to many organisms
Most important: provides stability to the web of life on Earth

2. The World Ocean
Even though we name individual oceans, they are all connected so they make up one large body of water-the world ocean
it is one large biome with many ecosystems and habitats
World ocean is divided into zones based on depth and distance from the shore
Depth zones: photic, aphotic, benthic zones
Shore distance zones: oceanic, neritic, intertidal zones

3. Oceanic Zone This is the open ocean
Largest zone in the ocean, 90% of the world ocean
Ranges in depth: 500 meters to 11,000 meters deep
Not much sunlight penetrates into the oceanic zone
Photic zone is only at the surface, about 200 m deep
Only phytoplankton are the producers
They convert CO2 into billions of tons of carbon each year
This provides the basic material for the bottom of the food web
Plankton is the food source for both large and small ocean animals: fish and whales

4. Aphotic zone-takes up most of the world ocean, but does not have much organism diversity
Limited by absence of sunlight
Organisms have to adapt to cold, dark, deep water
Feed on pieces of dead organic material that sinks down from surface
Detritus-tiny pieces of dead organic material that are food for organisms at the base of an aquatic food web
Clams, worms, sponges all feed on detritus

5. Ocean Water
Even though all ocean water is connected, it is not all the same
Differ in temperature, salinity, and density
Water near the equator gets more direct sunlight so it is warmer and more saline and (water evaporates b/c of the sunlight)
Water near the poles is colder, and less saline, and more dense
It is constantly getting more water from melting glaciers and ice caps

6. Ocean Currents
Ocean water flows in similar patterns all year, called currents
Currents are driven mostly by winds
They are pretty stable and remain the same even though there are small changes
Currents can cause water located very close together to be very different
Currents allow fish and organisms to travel quickly over long distances
Currents have kept pollutants dumped by people concentrated in areas
Fish become polluted and humans eat the fish
Ocean Dumping Act(1988) banned dumping industrial waste in the ocean

7. Neritic Zones
Continental shelf- the shallow border that surrounds the continents
Runs b/n the shore and 500 m below the surface of the water
Neritic zone- the ocean region b/n the edge of the continental shelf and the low tidemark
It’s usually shallow, so gets sunlight for photosynthesis
Only 10% of the ocean
But are the most productive b/c they get sunlight and are warm
Neritic zones include reefs and estuaries

8. Coral Reefs
Reef- natural structure built on a continental shelf
Coral reefs found in warm, tropical waters
Kelp reefs found in cold waters
Importance of coral reefs:
Home to huge variety of organisms
Breeding and feeding place for many fish
1/3 of all ocean fish live on or depend on coral reefs
Protects shoreline from erosion
Many coral reef organisms have medical benefits

9. Coral reefs are very fragile
Made of calcium carbonate skeletons of millions of tiny corals
Top layer is alive
Zooxanthellae alga lives inside tissue of coral
Alga perform photosynthesis and provide food to coral
Human Damage of coral reefs
Blast reefs to make harbors
Coral is harvested for jewelry
Fish are popular for home aquariums
Collecting the fish damages the coral

10. Water pollution damage
Toxic chemicals kill coral and organisms
Silt, sand, and topsoil wash into the water and make it cloudy, less light for photosynthesis
So can look at health of coral reef to determine the quality of water
When coral reefs start to die, start to investigate the water quality
Estuaries
Region where a freshwater source, usually mouth of a river, meets the saltwater of the ocean
Water is usually brackish here

11. Nutrients and sediments are mixed here
Many marine organisms breed here, commercially important
Function as buffer zone, filter sediments and pollutants from the water
Slow down floods and storm water
Humans use for boating, fishing, hunting
Neritic Zone Production
Sunlight can reach it, so photosynthesis occurs
Many mineral nutrients wash into the zone from the shore
Tides wash in fresh nutrients and O2, and takes away waste

12. Fringe reefs-grows just off shoreline
The reef will keep growing farther out
The reef closest to the shore will start to die, creating a channel
Forms a barrier reef- reefs that are separated from the shore by a channel
Great Barrier Reef in Australia is largest coral reef in world

14. Intertidal Zones This zone located along the shoreline
Alternates twice a day b/n periods of exposure at low tide and periods of submersion at high tide
2 high tides and 2 low tides each day
Any organisms living there must be able to withstand these constant changes, and pounding of water
Attach to rocks, burrow in sand
Often surrounded wetlands: salt marshes and mangrove swamps

15. Salt Marshes
Flat, muddy wetlands surround estuaries, bays, and lagoons
Mud floor is exposed during low tides, and submerged during high tides
Common in US coasts, especially east coast
Functions
Support migratory bird populations: feeding and resting grounds in b/n journeys
Plant life (grasses) support rich community of fish and invertebrates
Many shellfish and fish spend part of their life there, so they can be easily captured for sale
Plants are their food and protection

17. LOW TIDE
HIGH TIDE

18. Salt Marsh Formation
Streams flow into an estuary or shallow, neritic water
Sediments are deposited at the mouth of the stream, and build up forming a delta
the delta begins to sink. Subsidence-the weight of accumulated sediments cause the delta to sink under the water
The amount that sinks has to balance the amount that is deposited for a salt marsh to remain
This sinking and depositing of sediments causes the river to change its course many times

19. Mangrove Swamps Coastal wetland that occurs only in warm climates
Named after the mangrove plant that lives there
Mangroves cannot grow in areas that freeze more than 2 days a year
Mangroves can either be a tree or shrub, 800 species total, 10 live in US
Most common in US is red mangrove
Adaptations
Low O2 in swamps
Mangroves have roots that grow up and stick out of the water
Some have roots that grow high on the trunk, look like stilts

20. Mangrove swamps are being destroyed at a high rates
Make great commercial fish and shrimp ponds
Construction projects
Waste dumping

21. Review Questions
What is the most important thing that the marine biome provides for the Earth?
What is the name given to all of the oceans connected together?
What are the names of the 3 zones based on shore distance?
What is the largest zone, and how much space does it take up?
What is detritus? Why is it important?
Where is ocean water the warmest? Coldest?
What are ocean currents?
How do ocean currents contribute to polluting the ocean?
What is the neritic zone and how much space does it take up?
Why are coral reefs important?