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OCEANS IN JEOPARDY
Note to Instructors: This chapter touches on the topic of environmental science. Environmental
science is about solutions to the problems associated with human populations, and their
excessive use and pollution of the earth. A class session for this chapter is an opportunity to
discuss solutions that address a diversity of social levels: personal, local, national, and
internationals levels of industry and governments.
Chapter Outline
POLLUTION
Solid Wastes
Plastic
Commercial Dumping
Military Refuse
Chemical Pollution
Pesticides and Other Toxic Chemicals
Radioactive Wastes
Controlling Pollution
Biological Magnification
CLIMATE CHANGE
INTRODUCTION OF NONNATIVE
SPECIES
Introduction of Nonnative Species By
Ships’ Ballast
Introduction of Nonnative Species in
Aquaculture
Accidental Introduction of Nonnative
Beach Erosion
Interfering with Natural Processes
EPILOGUE
KEY CONCEPTS
Chapter Objectives
• Identify the major sources of pollution in the oceans and their impacts.
• Explain how anthropogenic climate change is altering the oceans.
Key Terms
photodegrade
hypoxic zones
longshore currents
Chapter Summary
1. Almost from the beginning of human history, people have dumped wastes into the
ocean. These include garbage, sewage, and industrial wastes. Currently there is a
proposal to dump radioactive and toxic wastes into oceanic subduction zones. As
populations in coastal areas have increased, so has the amount of wastes dumped
into coastal seas. This indiscriminate dumping has decreased the economic and
recreational value of some beaches, and in some instances has even posed health
hazards.
3. Agricultural and urban runoff contains a variety of pesticides as well as human and
4. Not all pollutants that enter the marine environment dissolve in the water. Some are
absorbed by particles, consumed by animals, and channeled through food chains.
5. Oil spills are another environmental problem. Although protective measures
6. Increased greenhouse gas emission since the Industrial Revolution has caused
increases in air and sea surface temperature around the globe. Left unchecked,
7. Nonnative marine species have detrimental effects after their introduction into new
8. The heavy development of coastal regions has severely damaged habitats, especially
wetlands and sandy beaches.
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Chapter Outline
I. Pollution
A. Solid wastes.
1. Plastic.
B. Chemical pollution.
1. Via land and air.
2. Pesticides and other toxic chemicals.
a. Persistence.
b. Effects of toxic compounds on plankton.
3. Petroleum pollution.
4. Oil spills.
a. BP’s Deepwater Horizon spill, Gulf of Mexico, 2010.
5. Oil spill cleanup.
C. Nutrient pollution.
1. Human wastes.
2. Agriculture wastes.
D. Radioactive wastes.
E. Controlling pollution.
F. Biological magnification.
II. Global Warming
A. Changes in species distributions.
III. Introduction of Nonnative Species
A. Introduction of nonnative species by ships’ ballast.
IV. Coastal Development
A. Wetlands.
B. Beaches.
1. Direct effects of beach use and development of marine life.
202 Oceans in Jeopardy
Suggestions for Presenting the Material
1. A field trip to any coastline will provide direct evidence of many of the negative
impacts of human activity. Find out which nonprofit environmental agencies in your
2. Are there nonnative invasive species in your locale? Contact your state’s department
of natural resources, or research any or all of the following species:
a. Alewife (Alosa pseudoharengus)
e. Zebra mussels (Dreissena polymorpha)
3. As a class, agree on a list of four projects in ocean conservation that students
think are most important to address in the upcoming decade. What are some
ways students can involve themselves in these issues?
Classroom Discussion Ideas
1. Discuss some of the ways that petroleum harms marine organisms and intertidal
habitats.
2. Discuss ways that students can reduce their use of plastics, as well as their carbon
Videos, Animations, and Websites
Videos
Global Warming: The Signs and the Science. (DVD, 2005)
Profiles people who are living with the grave consequences of a changing climate, as
well as the individuals, communities, and scientists inventing new approaches to
Strange Days on Planet Earth: The One Degree Factor.
Details specific evidence for the impact of climate change on natural systems, including
Ocean Animal Emergency. (DVD, NOVA, 2008)
Explores how a veterinary center for marine mammals works to save animals sickened
from various forms of pollution and tries to solve the mystery of what is killing them.
Florida’s Aquatic Plant Story. (DVD, 1990)
Case study describes the problems caused by exotic aquatic plants in Florida, and
introduces some of the typical methods to manage invasive aquatic plants.
Aquatic Invaders: The Rising Tide of Invasive Species. (DVD, 28 min, 1999)
Program presents the Great Lakes as a case study of the threats posed by nonnative
aquatic species and how scientists, policymakers, and the public are working to prevent
Animations
2010 Gulf of Mexico Oil Spill.
An interactive animation of the first 100 days of the BP/Transocean oil spill.
Websites
Ocean Conservancy: Marine Debris.
Information about International Coastal Cleanup Day, and how you can help.
204 Oceans in Jeopardy
Habitattitude.
Clearinghouse of information related to preventing the invasion and spread of
NOAA’s Climate Services.
Portal to resources dedicated to climate change awareness.
Suggested Answers to End of Chapter Questions
Multiple Choice
1. c. DDT
4. c. wetlands
Matching
1. c.
Short Answer
1. What environmental problems are associated with plastic trash?
Plastic trash is a major factor causing the death of marine vertebrates, either by
2. What are the major sources of oil pollution?
Major sources of oil pollution include: urban runoff, leaks from offshore drilling
3. What effect does an oil spill have on the ecology of a rocky shore?
Rocky shores are impacted in the following ways by oil spills: smothering of sessile
4. What activities are most damaging to wetlands?
Activities most damaging to wetlands are those associated with coastal
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5. Describe how toxins and other pollutants can enter ocean food chains.
Toxins and other pollutants enter ocean food chains via urban and agricultural
dumping; and through loss during transport on the ocean.
6. List some of the major problems associated with the agricultural runoff that enters the
ocean.
Major problems caused by agricultural runoff entering the ocean include
7. Describe how an oil spill causes injury to birds and mammals.
Oil spills harm birds and mammals by destroying the insulating capacity of their
8. How do changes in wind patterns caused by global warming affect marine
organisms?
Wind patterns drive the surface currents of the major oceans; in turn, these
9. Why does the introduction of a nonnative species frequently result in a decrease in the
number of native organisms?
Introduction of a nonnative species often results in decreasing populations of
10. What are some ways in which nonnative species are introduced into new
environments?
Nonnative species can be introduced inadvertently into new environments via
206 Oceans in Jeopardy
11. Describe how recreational and commercial use of beaches affects beach ecology.
Recreational and commercial uses of beaches negatively impacts beach ecology in
several ways: human foot traffic disturbs seashore animals and their burrows;
12. What are some causes and consequences of eutrophication?
High levels of nutrients entering aquatic systems cause eutrophication. The
Thinking Critically
1. Seashell collectors are frequently blamed for decreases in local mollusc populations in
Florida and other areas of the world. The collectors state that development and
pollution are more to blame than over-collecting. Do you think the collectors’
argument is valid? Explain.
Commercial seashell collectors can collect dead shells washed ashore, and/or they
can harvest live molluscs from the wild and kill them for their shells. No amount
2. What portion of the East Coast of the United States do you think would be more likely
to experience algal blooms resulting from agricultural runoff?
Coastal eutrophication affects all of the East Coast, but certain places experience
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3. An industrial waste is being dumped into the ocean off the coast of California, and
you are asked to determine if it is accumulating in the aquatic food chains. How
might you determine this?
You might sample representative organisms in the coastal food chain and assess
4. You find that a snail from the Philippines has been accidentally introduced into the
Bahamas and has spread to the reefs associated with most of the islands. What might
be done to control the spread of the nonnative snail and eradicate it?
To control the spread of the snail, first reduce the chance of its transport into new
Suggested InfoTrac® Articles
“From Relics to Reefs.” Harrigan, S. National Geographic, (2011).