CH. 11

The Marine Biome

http://people.eku.edu/ritchisong/birdbiogeography1.htm

The World Ocean

All oceans are connected, like one big ocean Called the world ocean

World ocean can be divided into zones Vertical zones: photic, aphotic, benthic Horizontal zones: oceanic, neritic, intertidal

http://www.dinosaurfact.net/

Oceanic Zone

Ocean Zone: open ocean Largest zone in ocean 90% of the surface area of the world ocean

Very deep About 200 m along continental shelf to 11,000 m

belowSunlight does not get down far into oceanic

zone

Oceanic Zone

Photic zone is the top layer Only producers of the open ocean are phytoplankton Each year the phytoplankton convert CO2 into billions

of tons of carbon All animals feed off of plankton, even humpback whales

Aphotic Zone Like the desert….little life Absence of sunlight limits the diversity and number of

organisms Organisms in this zone feed on pieces of dead organic

material Detritus: the tiny pieces of that are food for organisms

at the base of the food web

Ocean Water

Currents: pattern ocean waters flow All the ocean waters are connected BUT they don’t all

have the same characteristics Temperature varies due to different distances from

sun

http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/circulation/ocean_circulation.html

Near equator: higher temps. And Salinity

-near poles glaciers meltrelease fresh, cold water into ocean; less salty and colder

Ocean Water-Currents

Most fish and other organisms follow same current flow

Many people believe that because the ocean is so large chemicals and such will be diluted down and no longer harmful WRONG pollutants become concentrated in fish which humans

eat Ocean Dumping Act of 1988 banned the disposal of

industrial wastes at sea Trash still is able to accumulate due to the ocean

currents and winds

The World’s Dump

http://habitathabits.com/tag/great-garbage-patch/

Questions sect. 10.1

1. Why does the deep oceanic zone have no plants? What are the producers of the open ocean?

2. Compare the map in figure 11.3 (ocean currents) to the one in figure 1.8 on page 10. What type of winds drive the gulf stream current?

blogs.edf.org

Neritic Zone

Neritic zone: region between the edge of the continental shelf and the low tidemark Accounts for 10% of the ocean; shallow warmer water

Continental shelf: shallow border that surrounds the continent Between shore and 200 m below water surface

receives enough sunlight for photosynthesis to occur

Neritic Zone

Coral Reefs: natural structure built on a continental shelf Found warm, tropical waters

Kelp beds found in colder waters

Coral reefs are like rain forests Productive ecosystems Home to a variety of organisms, including fish Beneficial to humans: home to fish for fishing and

selling; protect the shoreline from erosion; have medicinal value

Neritic Zone

Coral Reef Reef is made of millions of tiny corals Only the top layer is alive Algae that lives inside reef carries out photosynthesis

Thus providing the reef with food Algae needs sunlight for photosynthesis- can’t grow below

certain depths Human Effect

Blasted with dynamite to make harbors and shipping canals

Harvested and sold for jewelry People collect fish in that area methods use damage

reef Water pollution

Chemicals kill reef Debris makes water cloudy decrease in

photosynthesis

Solcomhouse.com

Neritic Zone

Estuaries Region where freshwater source meets saltwater Salinity varies Many organisms use as an area to lay eggs Humans use for boating and fishing Important

filter sediments and pollutants from the water Slow water down (helpful after storms or floods)

Neritic Zone Productivity

How “productive” the neritic zone is depends on: Availability of sunlight Amount of nutrients Occurrence of tides

Tide brings nutrients to the reef and takes away the wastes

Barrier Reef: as a coral reef grows less oxygen and nutrients from the ocean are carried to the

corals closest to land, so a channel between the reef and land forms

solcomhouse.com

worldstravelr.blogspot.com

Questions

1. Where in the ocean does the neritic zone begin and end?

2. Continental shelves have been called the breadbaskets of the ocean. Explain this statement.

3. Some types of ecosystems recover from damage more quickly than others. Would you expect coral reefs to recover quickly from the types of damage described in this section. Why or why not?

Intertidal Zone

Located along the shoreline of oceanAlternates twice each day between periods of

exposure at low tide and periods of submersion at high tide

Organisms need be adapted to both exposure and submersion along with constant pounding• Attach to rocks• Burrow into sand

Intertidal ZoneIntertidal zones

because along shoreline they are often surrounded by salt marshes and mangrove swamps

Salt Marsh Flat, muddy wetlands Determined by tides

Low-mud flats are exposed High- submerged

Common on east coast and in the gulf of the U.S. Feeding and resting ground for migratory birds Abundant plant life supports a diversity of fish and

invertebrates Usually around estuaries

Intertidal Zone

Salt Marshes Form when streams flow into calm waters like an

estuary Slowing of water causes sediments flowing to be

deposited These sediments build up over time forming a DELTA SUBSIDENCE: weight of the sediments causes the

delta to sink under the water Balance and stability results when the rate of sediment

deposits equals that of subsidence

The Mississippi River delta undergoes a 5000 year cycle of sediment accumulation, subsidence, and therefore a change in the river’s course/shape

Intertidal Zone

Mangrove Swamps Coastal wetland that

occurs only in warm climates

FROST kills the plants…so mangroves exist in areas that don’t freeze for more than one or two days each year

Main plant: mangrove (woody plant - can be a tree or a shrub)

Water has very LITTLE dissolved oxygen

SOUTHEAST Asia swamps have developed into FORESTS

en.wikipedia.org

Questions

1. Why are salt marshes considered part of the intertidal zone?

2. Much of the Mississippi River has been contained by levees, dikes, and other flood-control structures. How do you think this change has affected the river’s delta?