© 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 78 Marine Pollution.
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Transcript of © 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 78 Marine Pollution.
© 2014 Pearson Education, Inc.
Mastery Check
Why are coral reefs biologically valuable? How are they being degrades by human impact? What is causing the disappearance of mangrove forests and salt marshes?
© 2011 Pearson Education, Inc.
Objectives:
• Define the term pelagic zone.
• Assess impacts from marine pollution.
• TED - Capt. Charles Moore of the Algalita Marine Research Foundation first discovered the Great Pacific Garbage Patch -- an endless floating waste of plastic trash. Now he's drawing attention to the growing, choking problem of plastic debris in our seas.
© 2011 Pearson Education, Inc.
Pelagic zone:The zone between the surface and floor of the ocean
Define the term pelagic zone.
© 2011 Pearson Education, Inc.
Assess impacts from marine pollution.
• Plastic trash accumulate in ocean regions where it is trapped by currents.
• Marine oil pollution results from non-point sources on land as well as from spills at sea from tankers and drilling platforms.
• Heavy metal contaminants in seafood affect human health.
• Nutrient pollution can lead to dead zones and harmful algal blooms.
© 2014 Pearson Education, Inc.
Marine Pollution
People use oceans as a sink for waste and pollutants
Even into the mid-20th century, coastal U.S. cities dumped trash and untreated sewage along their shores
Non-point-source pollution comes from all over Oil, plastic, chemicals, excess nutrients
Also sewage and trash from cruise ships and abandoned fishing gear
Over 25 years, Ocean Conservancy volunteers picked up 65 million kg (144 million lb) of waste from the world’s beaches
© 2011 Pearson Education, Inc.
Marine pollution
In 2008, 391,000 Ocean Conservancy
volunteers from 104 nations
picked up 3.1 million kg (6.8 million lb) of
trash from 27,000 km
(17,000 miles) of shoreline
© 2014 Pearson Education, Inc.
Plastic debris endangers marine life
Plastic items dumped into the sea harm or kill wildlife Organisms can become entangled in debris and
drown
May die from material eaten that they cannot expel
© 2014 Pearson Education, Inc.
Plastic debris endangers marine life
Areas where circulating currents converge called gyres bring and trap plastic trash The North Pacific Gyre contains the Great Pacific
Garbage Patch = an area larger than Texas where floating plastic bits outnumber organisms by a 6 to 1 margin
Plastic is designed not to break down so may drift for decades Breaks into tiny pieces over time
© 2014 Pearson Education, Inc.
Plastic debris endangers marine life
Trillions of tiny plastic pellets float in the oceans Some of the pellets sink, accumulating on the ocean floor
where they do not degrade
Organisms mistake the floating plastic for food The average fish in the great Pacific Garbage Patch had
over two pieces of plastic in its digestive tract
Over 40% of Albatross chick premature deaths have been attributed to pieces of plastic in their food
Over 260 species are affected by marine plastic debris
Leads to an estimated 100,000 marine mammal and 1 million seabird deaths each year
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Nets and plastic debris endanger life
Trillions of tiny plastic pellets float in the oceans and are eaten
© 2014 Pearson Education, Inc.
Plastic debris endangers marine life
Ingested plastics can also have toxic effects Plastics themselves contain harmful substances such as
bisphenol A and pthalates
May concentrate persistent organic pollutants
Floating debris can transport organisms great distances Some of these become invasive species
Plastics are not easily removed, so prevention is key The 2006 Marine Debris Research, Prevention, and
Reduction Act aids these efforts
Plastic pollution costs Asia over $1 billion in its fisheries and tourism industries
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Oil pollution comes from spills of all sizes
About 30% of oil and 50% of natural gas come from seafloor deposits North Sea, Gulf of Mexico
Drilling in other places is banned Spills could harm valuable fisheries
The Deepwater Horizon exploded off Louisiana’s coast in April 2010 Spilled 1800 gallons/min for 3 months Hit coasts of four states Even ocean floor species miles away were affected
© 2014 Pearson Education, Inc.
Oil pollution comes from spills of all sizes
Major spills make headlines Foul beaches, coat and kill animals, devastate
fisheries
Countless non-point sources produce most oil pollution Half of all oil comes from natural oil seeps
Also small boat leaks, runoff from land
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Oil spills have severe consequences
Major oil spills cause
severe environmental and economic
problems
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Oil pollution comes from spills of all sizes
Stricter regulations for oil tankers have been enacted by many governments
The U.S. Oil Pollution Act (1990) created a $1 billion prevention and cleanup fund Requires that all ships have double hulls by 2015
Spills from tankers have decreased over the last 30 years
© 2014 Pearson Education, Inc.
Toxic pollutants can contaminate seafood
Toxic pollutants can make food unsafe to eat
Mercury contamination from coal combustion and other sources bioaccumulates and biomagnifies Dangerous to children and pregnant or nursing women
Highest mercury levels will be in fish at the top of the food chain Avoid eating swordfish, shark, and albacore tuna
Eat seafood low in mercury (catfish, salmon, canned light tuna)
Avoid seafood from areas where health advisories have been issued
© 2014 Pearson Education, Inc.
Excess nutrients cause algal blooms
Nutrient runoff can allow explosive growth of marine algae populations
Harmful algal blooms = blooms where nutrients increase algae that produce powerful toxins Dinoflagellate algae toxins attack the nervous system Red tide = algae that produce red pigments that
discolor water Cause illness and death among wildlife and humans Economic loss to fishing industries and beach tourism
Reduce nutrient runoff Do not eat affected organisms
© 2011 Pearson Education, Inc.
TED Video
Charles Moore is founder of the Algalita Marine Research Foundation. He captains the foundation's research vessel, the Alguita, documenting the great expanses of plastic waste that now litter our oceans.
"His findings have gone a long way toward educating the science community, if not yet the public, on the magnitude of marine pollution and its impact on life -- all life."
- Thomas Kostigen, Discover MagazineCapt. Charles Moore On The Seas Of Plastic (7:23)