The Marine Biome CH. 11 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 below Sunlight 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/geog 101/textbook/circulation/ocean_circulation.ht ml 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 Solcomhouse.com 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 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 ocean Alternates 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 Zone Intertidal 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?