© 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 78 Marine Pollution.

© 2011 Pearson Education, Inc.

AP Environmental Science

Mr. Grant

Lesson 78

Marine Pollution


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?


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.


Pelagic zone:The zone between the surface and floor of the ocean

Define the term pelagic zone.


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.


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


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


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



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


Plastic trash is accumulating in the oceans



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


Nets and plastic debris endanger life

Trillions of tiny plastic pellets float in the oceans and are eaten



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


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


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


Oil spills have severe consequences

Major oil spills cause

severe environmental and economic

problems



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


Oil spills have

decreased

Recently, oil spills

have decreased


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


Toxic pollutants contaminate seafood


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


Excess nutrients cause algal blooms


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)

© 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 78 Marine Pollution.

Documents

Transcript of © 2011 Pearson Education, Inc. AP Environmental Science Mr. Grant Lesson 78 Marine Pollution.