AP Environmental Science
1999 Free-Response Questions
The materials included in these files are intended for non-commercial use by AP
teachers for course and exam preparation; permission for any other use must be
sought from the Advanced Placement Program. Teachers may reproduce them, in
whole or in part, in limited quantities, for face-to-face teaching purposes but may
not mass distribute the materials, electronically or otherwise. These materials and
any copies made of them may not be resold, and the copyright notices must be
retained as they appear here. This permission does not apply to any third-party
copyrights contained herein.
These materials were produced by Educational Testing Service (ETS), which develops and administers the examinations of the Advanced Placement Program for the
College Board. The College Board and Educational Testing Service (ETS) are dedicated to the principle of equal opportunity, and their programs, services, and
employment policies are guided by that principle.
The College Board is a national nonprofit membership association dedicated to preparing, inspiring, and connecting students to college and opportunity.
Founded in 1900, the association is composed of more than 3,900 schools, colleges, universities, and other educational organizations. Each year, the College Board
serves over three million students and their parents, 22,000 high schools, and 3,500 colleges, through major programs and services in college admission, guidance,
assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT™, the Advanced Placement
Program® (AP®), and Pacesetter®. The College Board is committed to the principles of equity and excellence, and that commitment is embodied in all of its
programs, services, activities, and concerns.
Copyright © 2001 by College Entrance Examination Board. All rights reserved. College Board, Advanced Placement Program, AP, and the acorn logo are registered
trademarks of the College Entrance Examination Board.
-2ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet, NOT on
the green insert. Where calculations are required, clearly show how you arrived at your answer. Where explanation
or discussion is required, support your answers with relevant information and/or specific examples.
1. On a field trip to two local ponds, a group of students observed a difference between the two ponds in the
diversity of worms and insect larvae living in the mud and debris near the edges of the ponds. Numerous factors,
both biotic and abiotic, influence the distribution of aquatic organisms.
(a) The students decided that they would investigate some of the abiotic factors. List three water-quality tests that
could be conducted and explain what information each test provides. Include in your answers a description of
the impact of each factor on the distribution of aquatic organisms.
(b) Larvae of a certain insect are found in pond A but not in pond B. Design a controlled experiment that would
help explain the observed distribution of these insect larvae. Be sure to include the following in your design.
1.
2.
3.
4.
Formulate a hypothesis.
Identify the variable that will be manipulated.
Outline the field and/or laboratory procedures that will be followed. Describe what data you will collect.
Discuss the possible results and relate them to the distribution of the insect.
(c) What are indicator species and how are they used to assess environmental quality? Give a specific example of
such a species and its use.
2. The development of plans for long-term resource management depends on understanding the patterns and
consequences of resource use.
(a) Describe what makes a resource renewable or nonrenewable. Give a specific example of a renewable
resource and of a nonrenewable resource.
(b) Describe and compare total resource use per capita in developed and developing countries.
(c) What is meant by sustainable resource use? Give an example.
(d) Economic policies and practices affect society’s progress toward achieving sustainable resource use.
Discuss one policy or practice that facilitates this progress, and one that impedes it.
-3-
Ozone
Carbon Monoxide
Carbon Monoxide
0.160
0.140
0.120
0.100
0.080
0.060
0.040
0.020
0.000
19
1976
1977
1978
7
19 9
1980
1981
1982
19 83
19 84
8
19 5
1986
1987
1988
8
19 9
1990
1991
9
19 2
19 93
19 94
95
Ozone (ppm)
ATMOSPHERIC CONCENTRATIONS OF OZONE
AND CARBON MONOXIDE
Year
Particulates
Lead
Particulates
1.600
1.400
1.200
1.000
0.800
0.600
0.400
0.200
0.000
19
1976
1977
1978
7
19 9
1980
1981
1982
19 83
19 84
8
19 5
1986
1987
1988
8
19 9
1990
1991
9
19 2
19 93
19 94
95
Lead (µg m–3)
ATMOSPHERIC CONCENTRATIONS OF LEAD
AND PARTICULATE MATTER
Year
3. The six criteria pollutants used by the Environmental Protection Agency to assess air quality in the United
States are NO 2 , SO 2 , carbon monoxide, lead, ozone, and particulates. The graphs above show trends in the
concentration of four of these in a certain city in the United States.
(a) Describe and compare the concentration trends for ozone and lead. Calculate the percentage change in each
from 1978 to 1988.
(b) For either ozone or lead, identify the major source(s) of that pollutant and describe the main physiological
effects in humans.
(c) For either particulates or carbon monoxide, identify the major source(s) of that pollutant and describe the most
effective method of reducing the concentration of the pollutant in the atmosphere.
-44. The following is an excerpt from a newspaper article describing a controversy.
Pesticide Use in Agriculture—A Controversy
Recently, Jonesville County inhabitants have been embroiled in a controversy regarding the use of pesticides
on crops grown in the county. The Jonesville Express interviewed county residents for opinions on pesticide use.
Below is a sampling of their responses.
Charles Ehler, farmer: “I’m not going to use those pesticides because I don’t want to end up with leukemia.”
Maurice Gordon, farmer: “The people who oppose the use of pesticides should have to decide which third of
the world would starve.”
Wendell Mullison, chemical salesman: “The health risks are minimal because these chemicals have been
intensively tested by the chemical companies.”
Robert Rodriguez, Environmental Protection Agency employee: “I worry about pesticides that find their way
into groundwater. My agency has trouble keeping up with the new developments in farm chemistry. We don’t
even test the water for most of the pesticides that are in use today.”
Bessie Smith, 80-year-old resident: “I’m against pesticides. When those planes spray on the farm next to me,
most of those chemicals end up in my yard.”
Alice Evans, farmer: “I couldn’t earn a living without pesticides. My farm would not make a profit.”
Judy Johnson, college professor: “We’re in a vicious cycle. We develop pesticides, apply them, and the pests
evolve resistance. Then we have to do it all over again.”
Ben Jackson, librarian: “Pesticides are much safer than they used to be. The newer pesticides only affect
specific pests and break down more quickly in the environment.”
(a) Select four of the people interviewed. Provide a concise argument, based on scientific principles, that supports
or refutes each individual’s viewpoint.
(b) Identify one specific pest and explain its adverse effects on either agriculture or human health. Describe a
viable method, other than the use of pesticides, of controlling this pest.
END OF EXAMINATION
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2000 Advanced Placement Program®
Free-Response Questions
The materials included in these files are intended for use by AP® teachers for course
and exam preparation in the classroom; permission for any other use must be
sought from the Advanced Placement Program. Teachers may reproduce them, in
whole or in part, in limited quantities, for face-to-face teaching purposes but may
not mass distribute the materials, electronically or otherwise. These materials and
any copies made of them may not be resold, and the copyright notices must be
retained as they appear here. This permission does not apply to any third-party
copyrights contained herein.
These materials were produced by Educational Testing Service (ETS), which develops and administers the examinations of the Advanced Placement
Program for the College Board. The College Board and Educational Testing Service (ETS) are dedicated to the principle of equal opportunity, and their
programs, services, and employment policies are guided by that principle.
The College Board is a national nonprofit membership association dedicated to preparing, inspiring, and connecting students to college and opportunity.
Founded in 1900, the association is composed of more than 3,800 schools, colleges, universities, and other educational organizations. Each year, the
College Board serves over three million students and their parents, 22,000 high schools, and 5,000 colleges, through major programs and services in college
admission, guidance, assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®,
the Advanced Placement Program® (AP®), and Pacesetter®. The College Board is committed to the principles of equity and excellence, and that
commitment is embodied in all of its programs, services, activities, and concerns.
Copyright © 2000 by College Entrance Examination Board and Educational Testing Service. All rights reserved. College Board, Advanced Placement
Program, AP, and the acorn logo are registered trademarks of the College Entrance Examination Board.
2000 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this booklet, NOT on the
green insert. Where calculations are required, clearly show how you arrived at your answer. Where explanation or
discussion is required, support your answers with relevant information and/or specific examples.
1. A large, coal-fired electric power plant produces 12 million kilowatt-hours of electricity each day. Assume that
an input of 10,000 BTU’s of heat is required to produce an output of 1 kilowatt-hour of electricity.
(a) Showing all steps in your calculations, determine the number of
(i) BTU’s of heat needed to generate the electricity produced by the power plant each day,
(ii) pounds of coal consumed by the power plant each day, assuming that one pound of coal yields 5,000
BTU’s of heat,
(iii) pounds of sulfur released by the power plant each day, assuming that the coal contains one percent
sulfur by weight.
(b) The Environmental Protection Agency (EPA) standard for power plants such as this one is that no more than
1.2 pounds of sulfur be emitted per million BTU’s of heat generated. Using the results in part (a), determine
whether the power plant meets the EPA standard.
(c) Describe two ways by which a fuel-burning electric power plant can reduce its sulfur emissions.
(d) Discuss why sulfur emissions from coal-fired power plants are considered an environmental problem and
describe one negative effect on an ecosystem that has been associated with sulfur emissions.
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-2-
2000 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. After reading the following editorial from The Fremont Daily, answer the questions that follow.
IS RECYCLING SMART ECONOMICS?
Debates about recycling often become highly charged and passionate. Over the past decade some headlines
have heralded that “trash is treasure” while others have proclaimed that “recycling is garbage.”
The antagonists in these debates are disagreeing over public policy and its role in shaping decisions about
resource use. Both sides in these debates frequently have broad policy agendas that go far beyond choosing
the most efficient way to manage solid waste. Both sides also promote their political agendas with
unsupported assertions and incomplete information. Determining what amount of recycling will result in
efficient resource use requires systematic analysis.
Proponents of recycling argue that recycling saves resources. For example, most manufacturers of aluminum
cans currently depend on recycled aluminum for more than 50% of their needs. This recycled input reduces
the economic and environmental costs associated with mining and landfills.
A common argument for the antirecycling side is that recycling wastes resources. It takes resources to
recycle. For example, it takes human effort to sort aluminum cans from other trash and energy to move
aluminum cans from the consumer back to the manufacturer.
It may not make economic sense to recycle all materials or all of any single material, but numerous studies
have shown that there are net benefits to society at low or modest levels of recycling most materials. The
question is, Which has the higher environmental cost: using recovered materials or using virgin materials?
Do recovered or virgin materials cost more in resources? The answer is complex and changing.
Your next environmental decision is fast approaching. Should you put this copy of The Fremont Daily in the
recycling bin or should you put it in the trash?
(a) Consider the arguments regarding aluminum presented in the editorial, then make
(i) a similar argument in favor of recycling the newspaper, and
(ii) a similar argument against recycling the newspaper.
(b) For each of the following, describe two pieces of scientific information that would be needed to evaluate
(i) the environmental benefits of recycling the newspaper, and
(ii) the environmental costs of recycling the newspaper.
(c) If a community can afford to begin a recycling program for either aluminum or newspaper, but not both,
which one would you recommend to be recycled? Provide two reasons why your recommendation is better
than the alternative.
(d) Discuss two difficulties that the community might face in implementing the recycling program in part (c).
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-3-
2000 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Species such as the dusky seaside sparrow, the passenger pigeon, and the woolly mammoth are extinct.
Populations of other species have declined to the point where they are designated as threatened or endangered.
(a) Identify one threatened or endangered species and explain why its population has declined.
(b) Describe three characteristics of organisms that would make them particularly vulnerable to extinction.
(c) Present three arguments in favor of the maintenance of biodiversity.
(d) Name and describe one United States federal law or one international treaty that is intended to prevent the
extinction of species.
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-4-
2000 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. The figures above show the age structures of human populations in three countries, X, Y and Z.
(a) Which of the three countries has the largest rate of population growth? Which has the smallest rate? Explain.
(b) Compare the infant mortality rates that are likely in Countries X and Y. Explain your reasoning.
(c) Describe the changes in both the birth rate and the death rate for a country making the transition from a
preindustrial society to an industrial society.
(d) Describe one incentive that the government of a country could offer its citizens that would favor a reduction
in the growth rate of its population. Explain how this incentive would work, and describe one possible
drawback.
END OF EXAMINATION
Copyright © 2000 College Entrance Examination Board and Educational Testing Service. All rights reserved.
AP is a registered trademark of the College Entrance Examination Board.
-5-
AP Environmental Science
2001 Free-Response Questions
The materials included in these files are intended for use by AP teachers for course
and exam preparation in the classroom; permission for any other use must be
sought from the Advanced Placement Program. Teachers may reproduce them, in
whole or in part, in limited quantities, for face-to-face teaching purposes but may
not mass distribute the materials, electronically or otherwise. These materials and
any copies made of them may not be resold, and the copyright notices must be
retained as they appear here. This permission does not apply to any third-party
copyrights contained herein.
These materials were produced by Educational Testing Service (ETS), which develops and administers the examinations of the Advanced Placement
Program for the College Board. The College Board and Educational Testing Service (ETS) are dedicated to the principle of equal opportunity, and their
programs, services, and employment policies are guided by that principle.
The College Board is a national nonprofit membership association dedicated to preparing, inspiring, and connecting students to college and opportunity.
Founded in 1900, the association is composed of more than 3,900 schools, colleges, universities, and other educational organizations. Each year, the
College Board serves over three million students and their parents, 22,000 high schools, and 3,500 colleges, through major programs and services in
college admission, guidance, assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the
PSAT/NMSQT™, the Advanced Placement Program® (AP®), and Pacesetter®. The College Board is committed to the principles of equity and
excellence, and that commitment is embodied in all of its programs, services, activities, and concerns.
Copyright © 2001 by College Entrance Examination Board. All rights reserved. College Board, Advanced Placement Program, AP, and the acorn logo
are registered trademarks of the College Entrance Examination Board.
2001 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
NO CALCULATORS MAY BE USED ON THIS EXAMINATION
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Answer the questions below regarding the heating of a house in the Midwestern United States. Assume the
following.
• The house has 2,000 square feet of living space.
• 80,000 BTUs of heat per square foot are required to heat the house for the winter.
• Natural gas is available at a cost of $5.00 per thousand cubic feet.
• One cubic foot of natural gas supplies 1,000 BTUs of heat energy.
• The furnace in the house is 80 percent efficient.
(a) Calculate the following, showing all the steps of your calculations, including units.
(i) The number of cubic feet of natural gas required to heat the house for one winter
(ii) The cost of heating the house for one winter
(b) Identify and describe three actions the residents of the house could take to conserve heat energy
and lower the cost of heating the house.
(c) The residents decide to supplement the heating of the house by using a wood-burning stove.
Discuss two environmental impacts, one positive and one negative, of using the wood-burning stove.
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2
2001 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. After reading the following excerpt from an article about the interrelationships among organisms in an oak
forest, answer parts (a), (b), and (c), which follow.
Chain Reactions Linking Acorns to Gypsy Moth Outbreaks and Lyme Disease Risk
Oak trees (Quercus spp.) produce large autumnal acorn crops every two to five years, and
produce few or no acorns during intervening years. Acorns are a critical food for white-footed
mice (Peromyscus leucopus). Mice are important predators of the pupal stage of the gypsy moth
(Lymantria dispar). This introduced insect periodically undergoes outbreaks that defoliate
millions of hectares of oak forests, decreasing tree growth, survival, and acorn crop production.
An abundance of acorns provides food for white-tailed deer (Odocoileus virginianus). Mice and
deer are the primary hosts of the black-legged tick (Ixodes scapularis), which carries Lyme
disease.
(a) In the space provided below, diagram a food web based on the interrelationships of the organisms identified
in the excerpt.
(b) Design a controlled experiment that tests the relationship between acorn production and gypsy moth
population. Include the hypothesis that the experiment tests.
(c) Briefly describe a strategy that uses integrated pest management for the control of the black-legged tick
population.
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3
2001 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. In recent years, results from scientific studies have increased public awareness of the possible damage to human
health from exposure to indoor air pollution.
(a) Identify two specific indoor air pollutants and, for each, discuss the following.
(i) The type of building most affected by the pollutant
(ii) Source(s) of the pollutant
(iii) The pollutant’s effects on human health
(iv) The method(s) of prevention or cleanup of the pollutant
(b) According to the Environmental Protection Agency, at least 17 percent of the four million
commercial buildings in the United States can be considered “sick buildings.”
(i) Explain what is meant by the term “sick building.”
(ii) Describe the criteria used for determining whether a building is “sick.”
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4
2001 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Students in an environmental science class at Fremont High School tested the water quality in a stream near their
school. They were concerned about the possible pollution of the stream, which flows through a farm on which
hogs are raised. Shown below are a diagram that indicates the sites where the students collected water samples
(labeled A through D, upstream to downstream) and a table of the results of the students’ water tests.
Results of Water Tests
A
B
C
D
Dissolved Oxygen
(ppm)
6.4 ± 0.3
2.5 ± 0.1
3.0 ± 0.2
5.8 ± 0.2
Phosphate
(ppm)
0.9 ± 0.05
1.2 ± 0.09
1.1 ± 0.08
1.0 ± 0.09
Nitrate
(ppm)
0.9 ± 0.3
19.3 ± 1.1
12.5 ± 1.0
6.2 ± 0.5
pH
5.5
5.4
5.6
5.4
(a) Assess the likelihood that animal waste is contaminating the water. Discuss the scientific basis of your
assessment.
(b) Describe two additional tests that could be used in monitoring the quality of the water in the stream. For
each test, describe the patterns you would expect from sites A through D.
(c) Describe a sequence of ecological changes that might result from the discharge of animal waste into a body
of water.
(d) The Clean Water Act was first passed in the United States in 1972 and has been amended several times since
then. Describe two specific provisions of this legislation that would be likely to apply to the quality of the
stream water.
END OF EXAMINATION
Copyright © 2001 by College Entrance Examination Board. All rights reserved.
Advanced Placement Program and AP are registered trademarks of the College Entrance Examination Board.
5
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2002 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Electric vehicles often have been proposed as an environmentally sound alternative to the gasoline engine for
transportation. In response to state initiatives, several car manufacturers now include electric vehicles among
their available models. In spite of these state initiatives, the penetration of electric vehicles into the transportation
sector of the United States, as well as other countries, remains modest.
(a) Identify and describe two environmental benefits to using electric vehicles in place of gasoline-powered
engines for transportation.
(b) Estimate the potential reduction in petroleum consumption (in gallons of gasoline per year) that could be
achieved in the United States by introducing electric vehicles under the following assumptions:
1. The mileage rate for the average car is 25 miles per gallon of gasoline.
2. The average car is driven 10,000 miles per year.
3. The United States has 150 million cars.
4. 10 percent of United States cars could be replaced with electric vehicles.
(c) Some people have suggested that electric vehicles only shift the emission of air pollutants from dispersed
sources to point sources. Explain and defend or refute this statement.
(d) Propose two potential new United States government policies that would encourage the widespread use of
electric vehicles. Explain.
2. The Colorado River runs 1,450 miles from the headwaters of the Rocky Mountains to the Gulf of California. The
river has many dams, aqueducts, and canals that divert water in order to supply water for electricity, irrigation,
recreation, and domestic use.
(a) Describe and discuss two environmental problems that are associated with water diversion.
(b) If there is a shortage of water, choices will have to be made as to whether water should be diverted to urban
areas, agricultural areas, or natural ecosystems. Make an argument for diverting water for urban
consumption and an argument for permitting the flow of water to natural areas.
(c) Identify another example (other than the Colorado River) of a large-scale water-diversion project. Discuss
two environmental problems that have resulted, or might result, from this project.
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2
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2002 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. An experiment is performed to test the toxicity of copper sulfate (CuSO4) using brine shrimp as a test organism.
Six different concentrations of CuSO4 solution are prepared in separate petri dishes, and 100 brine shrimp are
placed in each dish. After 48 hours, the number of brine shrimp that have died is counted and recorded. The
results of this experiment are shown in the table below.
CuSO4 Concentration (%)
Number of Dead Brine Shrimp
< 0.0001
0.001
0.01
0.1
1
10
10
10
20
55
90
100
(a) Plot these data on the blank semi-log graph provided below. Draw a smooth curve through the data points to
illustrate the overall trend of the data.
(b) Explain the meaning of the term LD50 (ED50). What is the LD50 concentration of CuSO4 for brine shrimp?
(c) Explain the meaning of the term “threshold level of toxicity”. What is the threshold level of toxicity of
CuSO4 for brine shrimp? Label this point on the graph.
(d) Provide one argument for extending these toxicity results to humans and one argument against doing so.
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2002 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Read the article below and answer the questions that follow.
(a) Describe what an El Niño is and clearly indicate where it occurs.
(b) Describe the connection between the climate change associated with an El Niño and the transmission of
diseases. Explain whether the article is correct in its reporting of the various disease epidemics that occur in
response to an El Niño.
(c) People in what part of the world would be most likely to be affected by this link between El Niño and
disease?
(d) Clearly describe two other important environmental problems associated with ENSOs.
END OF EXAMINATION
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4
AP® Environmental Science
2003 Free-Response Questions
The materials included in these files are intended for use by AP teachers
for course and exam preparation; permission for any other use must be
sought from the Advanced Placement Program®. Teachers may reproduce them, in
whole or in part, in limited quantities for noncommercial, face-to-face teaching
purposes. This permission does not apply to any third-party copyrights contained
herein. This material may not be mass distributed, electronically or otherwise.
These materials and any copies made of them may not be resold, and the
copyright notices must be retained as they appear here.
These materials were produced by Educational Testing Service® (ETS®), which develops and administers the examinations of the Advanced Placement
Program for the College Board. The College Board and Educational Testing Service (ETS) are dedicated to the principle of equal opportunity, and their
programs, services, and employment policies are guided by that principle.
The College Board is a national nonprofit membership association whose mission is to prepare, inspire, and connect students to college and opportunity.
Founded in 1900, the association is composed of more than 4,300 schools, colleges, universities, and other educational organizations. Each year, the
College Board serves over three million students and their parents, 22,000 high schools, and 3,500 colleges through major programs and services in
college admissions, guidance, assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the
PSAT/NMSQT®, and the Advanced Placement Program® (AP®). The College Board is committed to the principles of equity and
excellence, and that commitment is embodied in all of its programs, services, activities, and concerns.
For further information, visit www.collegeboard.com
Copyright © 2003 College Entrance Examination Board. All rights reserved. College Board, Advanced Placement Program, AP, AP Vertical Teams,
APCD, Pacesetter, Pre-AP, SAT, Student Search Service, and the acorn logo are registered trademarks of the College Entrance Examination Board.
AP Central is a trademark owned by the College Entrance Examination Board. PSAT/NMSQT is a registered trademark jointly owned by the
College Entrance Examination Board and the National Merit Scholarship Corporation. Educational Testing Service and ETS are registered trademarks of
Educational Testing Service. Other products and services may be trademarks of their respective owners.
For the College Board’s online home for AP professionals, visit AP Central at apcentral.collegeboard.com.
2003 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the following article from the Fremont Examiner.
(a) Support Dr. Tate’s assertion that “the leaf litter is critical to the survival of local species of forest plants.”
Include in your discussion the roles of leaf litter in a deciduous forest ecosystem.
(b) Describe THREE abiotic changes that would be likely to result if the exotic worms consumed all the leaf
litter in a single year.
(c) For one of the changes you identified in part (b), explain how the change could set the stage for the takeover
of Japanese stilt grass or other exotic species.
(d) Design a controlled experiment to determine whether the worms, in fact, do change the forest ecosystem.
Identify the environmental factor you will measure, and include the specific hypothesis you will test and the
data you will collect.
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2003 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. A certain fictional country called Industria is tracking its population data. In 1855, the first year vital statistics
were reported for the country, the population was 1.6 million, with a crude birth rate of 43 per 1,000. At that
time the population of Industria was growing quite slowly, because of the high death rate of 41 per 1,000. In
1875 the population began to grow very rapidly as the birth rate remained at its 1855 level, while the crude death
rate dropped dramatically to 20 per 1,000. Population growth continued to increase in the small country into the
late 1800’s, even though birth rates began to decline slowly.
In 1895 the crude birth rate had dropped to 37, and the death rate to 12 per 1,000. In that year (1895) a complete
census revealed that the population of Industria had grown to 2.5 million. By 1950 population growth gradually
began to decline as the death rate remained at its 1895 level, while the birth rate continued to decline to 22 per
1,000. In 1977 vital statistics revealed that the death rate was 10 per 1,000, and that population growth had
slowed even more to an annual rate of 0.4%. By 1990 Industria had reduced its birth rate to that of its now
constant, low death rate, and the population transition was complete.
(a) On the axes below, plot the crude birth-rate data from 1855 to 1990. Now plot the crude death-rate data on
the same axes. Clearly label the axes and the curves.
(b) What was the annual growth rate of Industria in 1950 ? What was the birth rate in Industria in 1977 ?
(c) Indicate TWO factors that might have accounted for the rapid decline in the death rate in Industria between
1855 and 1895. Indicate one specific reason why the birth rate might have been so high in 1855 and was so
slow to decrease between 1855 and 1950.
(d) Determine what the population size of Industria would have been in 1951 if the population had continued to
grow at the annual rate of growth recorded for Industria in 1895.
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2003 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Environmental conditions in coastal estuaries vary hourly and seasonally.
(a) Discuss TWO important causes for the variation in the temperature and/or salinity of an estuary. Be sure to
include the connection between each cause and temperature and/or salinity.
(b) Discuss TWO roles that coastal wetlands play that are ecologically important, and TWO roles that wetlands
play that are economically important.
(c) Identify and explain THREE ways in which humans have had a negative impact on or have degraded coastal
wetlands.
(d) Choose one of the negative human impacts you identified in part (c), and explain one environmental policy
and one economic incentive that could have prevented it.
4. The American whooping crane and the California condor are two of North America’s largest birds. Although
both are rare and endangered, they are protected, and large preserves are available for them. The two species,
however, seem to be responding differently to these conservation efforts.
In 1937, the whooping crane population was reduced to 14 individuals. It has since recovered; currently more
than 200 birds live and breed in the wild. In the preservation of endangered species, the whooping crane is a
success story. On the other hand, the California condor population declined rapidly so that no birds remained
in the wild between 1987 and 1992. Condors were reintroduced into the wild after 1992 and approximately
50 condors currently live in the wild in California and Arizona. However, the recovery program cannot yet
be considered a success.
(a) Identify and describe TWO major causes for the original decline of these species. (You may describe one
cause for each species or two causes for one species.)
(b) Describe TWO measures that have been taken to protect these species. (Specify which of the species
benefited from each measure.)
(c) Describe TWO important characteristics of an endangered species that would cause it to be slow to recover.
(d) Make one economic or ecological argument for protecting the condor, the whooping crane, or another
endangered species that you identify and make one economic or ecological argument against protecting it.
END OF EXAMINATION
Copyright © 2003 by College Entrance Examination Board. All rights reserved.
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students and parents at www.collegeboard.com/apstudents.
4
AP® Environmental Science
2004 Free-Response Questions
The materials included in these files are intended for noncommercial use by
AP teachers for course and exam preparation; permission for any other use
®
must be sought from the Advanced Placement Program . Teachers may
reproduce them, in whole or in part, in limited quantities, for face-to-face
teaching purposes but may not mass distribute the materials,
electronically or otherwise. This permission does not apply to any
third-party copyrights contained herein. These materials and any copies
made of them may not be resold, and the copyright notices
must be retained as they appear here.
The College Board is a not-for-profit membership association whose mission is to connect students to college success and opportunity.
Founded in 1900, the association is composed of more than 4,500 schools, colleges, universities, and other educational organizations. Each year, the
College Board serves over three million students and their parents, 23,000 high schools, and 3,500 colleges through major programs and services in
college admissions, guidance, assessment, financial aid, enrollment, and teaching and learning. Among its best-known programs are the SAT®, the
PSAT/NMSQT®, and the Advanced Placement Program® (AP®). The College Board is committed to the principles of
excellence and equity, and that commitment is embodied in all of its programs, services, activities, and concerns.
For further information, visit www.collegeboard.com
Copyright © 2004 College Entrance Examination Board. All rights reserved. College Board, Advanced Placement Program, AP, AP Central,
AP Vertical Teams, APCD, Pacesetter, Pre-AP, SAT, Student Search Service, and the acorn logo are registered trademarks of the
College Entrance Examination Board. PSAT/NMSQT is a registered trademark jointly owned by the
College Entrance Examination Board and the National Merit Scholarship Corporation.
Educational Testing Service and ETS are registered trademarks of Educational Testing Service.
Other products and services may be trademarks of their respective owners.
For the College Board’s online home for AP professionals, visit AP Central at apcentral.collegeboard.com.
2004 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the editorial below and answer the questions that follow.
(a) On the basis of the article above, indicate one human activity that releases mercury into the environment.
Describe how mercury is transported from that source and enters aquatic systems, often hundreds of miles
away.
(b) Describe TWO ways that the amount of mercury released into the environment from the source in part (a)
could be reduced.
(c) Explain why there are greater health risks associated with eating large predatory fish, such as tuna and sea
bass, than from eating small nonpredatory fish.
(d) Identify a toxic metal other than mercury that has a negative impact on human health and describe how it is
introduced into the environment. Describe an acute sublethal effect on humans that results from exposure
to this metal.
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2004 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. West Fremont is a community consisting of 3,000 homes. A small coal-burning power plant currently supplies
electricity for the town. The capacity of the power plant is 12 megawatts (MW) and the average household
consumes 8,000 kilowatt hours (kWh) of electrical energy each year. The price paid to the electric utility by
West Fremont residents for this energy is $0.10 per kWh. The town leaders are considering a plan, the West
Fremont Wind Project (WFWP), to generate their own electricity using 10 wind turbines that would be located
on the wooded ridges surrounding the town. Each wind turbine would have a capacity of 1.2 MW and each
would cost the town $3 million to purchase, finance, and operate for 25 years.
(a) Assuming that the existing power plant can operate at full capacity for 8,000 hrs/yr, how many kWh of
electricity can be produced by the plant in a year?
(b) At the current rate of electrical energy use per household, how many kWh of electrical energy does the
community consume in one year?
(c) Compare your answers in (a) and (b) and explain why you would or would not expect the numbers to be
the same.
(d) Assuming that the electrical energy needs of the community do not change during the 25-year lifetime of the
wind turbines, what would be the cost to the community of the electricity supplied by the WFWP over 25
years? Express your answer in dollars/kWh.
(e) Identify and explain TWO environmental benefits to West Fremont of switching from coal to wind power
and TWO environmental costs to West Fremont of switching from coal to wind power.
3. Radioactive isotopes are widely used in the field of medicine, in the generation of electricity, and in the military.
The use of radioactive isotopes has increased significantly over the past fifty years, leading to a corresponding
increase in the amount of radioactive waste produced. The question of how to deal with radioactive waste is
a topic of ongoing environmental concern.
(a) Explain how the properties of low-level radioactive waste differ from those of high-level radioactive waste
and how these properties lead to different storage requirements. For one of the two types of radioactive
waste, give an example of a specific isotope that may be present in the waste, and explain how human
activity generates the waste.
(b) The United States Department of Energy recently chose Yucca Mountain in Nevada as the site for the deep
underground burial of high-level radioactive waste. Describe THREE characteristics of an ideal deep
underground storage site for high-level radioactive waste.
(c) Identify TWO other options that have been suggested for the long-term management of radioactive waste.
Discuss the feasibility of each method.
(d) Exposure to high levels of ionizing radiation has adverse effects on human health and can result in
immediate death. Identify one sublethal adverse effect on human health that can result from exposure
to ionizing radiation, and explain how this effect is caused by the radiation.
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2004 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Suppose that you have just started a summer internship working for a cooperative extension service, where you
will collect soil samples, conduct laboratory and field tests, and make recommendations on soil conservation and
agricultural practices.
(a) Identify and describe one chemical soil test and one physical soil test that could be performed and explain
how the results of these tests will allow the cooperative extension service to make specific recommendations
for sustainable agriculture.
(b) Explain one advantage and one disadvantage to using inorganic commercial fertilizers.
(c) Describe TWO soil conservation practices that are designed to decrease soil erosion.
(d) Identify one biome that is characterized by soil that is rich in humus. Describe how humus originated in the
soils of this biome and TWO ways that humus improves soil conditions for plant growth.
END OF EXAMINATION
4
AP® Environmental Science
2005 Free-Response Questions
The College Board: Connecting Students to College Success
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the association is composed of more than 4,700 schools, colleges, universities, and other
educational organizations. Each year, the College Board serves over three and a half million students and their parents, 23,000
high schools, and 3,500 colleges through major programs and services in college admissions, guidance, assessment, financial aid,
enrollment, and teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®, and the Advanced
Placement Program® (AP®). The College Board is committed to the principles of excellence and equity, and that commitment is
embodied in all of its programs, services, activities, and concerns.
Copyright © 2005 by College Board. All rights reserved. College Board, AP Central, APCD, Advanced Placement Program, AP,
AP Vertical Teams, Pre-AP, SAT, and the acorn logo are registered trademarks of the College Entrance Examination Board.
Admitted Class Evaluation Service, CollegeEd, Connect to college success, MyRoad, SAT Professional Development, SAT
Readiness Program, and Setting the Cornerstones are trademarks owned by the College Entrance Examination Board.
PSAT/NMSQT is a registered trademark of the College Entrance Examination Board and National Merit Scholarship
Corporation. Other products and services may be trademarks of their respective owners. Permission to use copyrighted College
Board materials may be requested online at: http://www.collegeboard.com/inquiry/cbpermit.html.
Visit the College Board on the Web: www.collegeboard.com.
AP Central is the official online home for the AP Program and Pre-AP: apcentral.collegeboard.com.
2005 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the following article from the Fremont Examiner.
(a) For one new disease and one old disease named in the article above, explain how the disease is transmitted
through the human population and describe an effective method for controlling the spread of the disease.
(b) For one of the two diseases you chose in part (a), identify one environmental factor that contributed to the
emergence or reemergence of the disease and explain how that factor influenced the increased incidence of
the disease.
(c) Provide a rationale to support Dr. Amodie’s statement as quoted in the article.
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2005 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(d) The graphs above show the mortality from infectious diseases in the United States since 1900. Identify an
infectious disease that made an important contribution to the trend of increasing mortality rates that began
in about 1980 and explain one major cause of the increased rate of mortality from that disease.
2. Between 1950 and 2000, global meat production increased from 52 billion kilograms to 240 billion kilograms.
During this period, the global human population increased from 2.6 billion to 6.0 billion.
(a) Calculate the per capita meat production in 1950 and in 2000.
(b) Use the values from part (a) to calculate the change in global per capita meat production during
this 50-year period as a percentage of the 1950 value.
(c) Discuss why it is more efficient to produce grain for human consumption than to produce meat
for human consumption. In your answer, consider both land use and energy use.
(d) Describe TWO environmental consequences of the increase in the production of meat for
human consumption.
(e) Identify and explain one potential advantage and one potential disadvantage for human health
of a diet that contains very little meat.
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2005 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Most of the coal mined in the United States today comes from surface (strip) mines. In surface mining, the
vegetation, soil, and rock covering the coal (referred to as overburden) are removed and set aside. After the coal
has been hauled away, good conservation practices require that the overburden be replaced and the surface be
restored to its original condition. Land restoration may be difficult in some regions, due to factors such as the
local climate, the thickness of the coal seam, the extent of the overburden, and the sulfur content of the coal.
(a) Describe the steps that should be taken to restore the land after the overburden has been replaced.
(b) Explain why the restoration of the land would likely be more difficult in an arid climate
(less than ten inches of precipitation per year).
(c) Describe one environmental impact that the sulfur content of the remaining coal and the tailings
would have on the reclamation process and suggest a possible remedy.
(d) Other than mining and reclamation, describe TWO environmental impacts of using coal for energy.
(e) Explain why per capita coal consumption in the United States is likely to increase.
4. The Alaskan National Wildlife Refuge (ANWR) on Alaska’s North Slope is frequently in the news because
petroleum geologists estimate that there are billions of barrels of economically recoverable oil beneath the
surface of its frozen tundra. According to a 1998 United States Geological Survey (USGS) estimate, ANWR
could contain up to 10 billion barrels of technically recoverable oil. Oil company officials advocate opening
the refuge to oil exploration and the subsequent development of its petroleum resources. Environmentalists
argue that oil exploration and development will damage this fragile ecosystem and urge Congress to protect
ANWR by designating it as a wilderness area.
(a) The United States consumes approximately 20 million barrels of oil per day. According to the USGS
estimate, for how many days would the technically recoverable oil resource in ANWR supply the total
United States demand for oil?
(b) Describe TWO characteristics of arctic tundra that make it fragile and explain how these two characteristics
make the tundra particularly susceptible to damage from human impacts.
(c) Identify TWO activities that would be associated with the development of ANWR petroleum resources and
describe a substantial environmental impact of each in ANWR.
(d) Identify and describe TWO major end uses of the 20 million barrels of oil that the United States consumes
each day and for each use describe a conservation measure that would substantially reduce United States
consumption.
END OF EXAM
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AP® Environmental Science
2006 Free-Response Questions
The College Board: Connecting Students to College Success
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the association is composed of more than 5,000 schools, colleges, universities, and other
educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and
3,500 colleges through major programs and services in college admissions, guidance, assessment, financial aid, enrollment, and
teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®, and the Advanced Placement
Program® (AP®). The College Board is committed to the principles of excellence and equity, and that commitment is embodied
in all of its programs, services, activities, and concerns.
© 2006 The College Board. All rights reserved. College Board, AP Central, APCD, Advanced Placement Program, AP, AP
Vertical Teams, Pre-AP, SAT, and the acorn logo are registered trademarks of the College Board. Admitted Class Evaluation
Service, CollegeEd, connect to college success, MyRoad, SAT Professional Development, SAT Readiness Program, and Setting the
Cornerstones are trademarks owned by the College Board. PSAT/NMSQT is a registered trademark of the College Board and
National Merit Scholarship Corporation. All other products and services may be trademarks of their respective owners.
Permission to use copyrighted College Board materials may be requested online at:
www.collegeboard.com/inquiry/cbpermit.html.
Visit the College Board on the Web: www.collegeboard.com.
AP Central is the official online home for the AP Program: apcentral.collegeboard.com.
2006 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Upon receiving notice from their electric utility that customers with solar power systems are permitted to sell
excess power back to the utility, an Arizona family is considering the purchase of a photovoltaic solar energy
system for their 2,700-square-foot suburban home. The initial costs of the systems they are considering range
from $7,000 to $30,000. While gathering information prior to making a decision, the homeowners find the
following information at the Web site of the United States Department of Energy.
Stand-Alone vs. Grid-Connected Systems
Stand-alone systems produce power independently of the utility grid. In some off-the-grid locations as
near as one-quarter mile from the power lines, stand-alone photovoltaic systems can be more costeffective than extending power lines. Direct-coupled systems need no electrical storage because they
operate only during daylight hours, but most systems rely on battery storage so that energy produced
during the day can be used at night. Some systems, called hybrid systems, combine solar power with
additional power sources such as wind or diesel.
Grid-connected photovoltaic systems supply surplus power back through the grid to the utility and take
from the utility grid when the home system’s power supply is low. These systems remove the need for
battery storage, although arranging for the grid interconnection can be difficult. In some cases, utilities
allow net metering, which allows the owner to sell excess power back to the utility.
(a) Describe one environmental benefit and one environmental cost of photovoltaic systems.
(b) From the two types of solar systems described on the government Web site, select the system (either standalone or grid-connected) that you think best meets the needs of the homeowners. Write an argument to
persuade them to purchase the system you selected. Include the pros and cons of each system in your
argument.
(c) Describe TWO ways that government or industry could promote the use of photovoltaic power systems for
homeowners in the future.
(d) Describe TWO ways that homeowners could use passive solar designs and/or systems and, for each way,
explain how it would reduce the homeowners’ energy costs.
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2006 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. According to atmospheric temperature and CO2 concentration records derived from Antarctic ice cores, Earth’s
climate has undergone significant changes over the past 200,000 years. Two graphs are shown below. The upper
graph shows the variation in atmospheric CO2 concentration, and the lower graph shows the variation in air
temperature. Both graphs cover the same time period from approximately 200,000 years ago up until the year
1950, which is represented as year 0 on the graphs.
(a) Answer the following questions that relate to the graphs above. Remember that for any calculations you
must clearly indicate how you arrived at your answer. Answers must also include appropriate units.
(i) Determine the net change in atmospheric CO2 concentration between 140,000 years ago and 125,000
years ago.
(ii) Calculate the ratio of the change in mean global temperature to the change in atmospheric CO2
concentration between 140,000 years ago and 125,000 years ago.
(iii) Scientists predict that between 1950 and 2050, the atmospheric CO2 concentration will increase by
200 ppm. Predict the change in mean global temperature between 1950 and 2050 using the ratio that
you calculated in part (ii).
(iv) Describe one major assumption that was necessary to make the prediction in part (iii) above. Discuss
the validity of the assumption.
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2006 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(b) Identify and describe TWO major causes for the predicted 200 ppm increase in atmospheric CO2
concentration between 1950 and 2050.
(c) Identify TWO gases other than CO2 that contribute to the anthropogenic increase in mean global
temperature. For each gas, describe a major human activity that leads to its release.
3. The city of Fremont has a large brownfield located along the Fremont River. The brownfield is a former
industrial site where contamination by hazardous chemicals impedes redevelopment. The city council is
considering two options for reclaiming the brownfield. The first option is to excavate and remove the
contaminated soil, and the second option is to decontaminate the soil on the site using vegetation.
(a) Assume that the city council chooses the first option. Describe TWO problems that result from removing the
contaminated soil from the brownfield.
(b) Assume that the city council chooses the second option. Explain how vegetation could be used to
decontaminate the soil. Discuss one advantage and one disadvantage of using this reclamation method.
(c) Describe and explain one environmental benefit and one societal benefit of brownfield reclamation.
(d) Identify and describe
(i) one method currently used to reduce the production of hazardous waste and
(ii) one method of legally disposing of hazardous waste.
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2006 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. The graph above shows the decline in the catch of groundfish (such as cod, haddock, and flounder) from
Georges Bank from 1965 to 1995. This decline in the fish harvest resulted in the closure of large portions of the
fishery.
(a) Identify the five-year period during which the greatest rate of decline in the fish harvest took place. For that
five-year period, calculate the rate of decline in the fish harvest, in metric tons per year. Show clearly how
you determined your answer.
(b) Choose any TWO commercial fishing practices from the list below. For each of your choices, describe the
practice and explain the role it plays in the depletion of marine organisms.
• Bottom trawling
• Long-line fishing
• Using drift nets/gill nets/purse seines
• Using sonar
(c) Identify one international regulation or United States federal law that applies to the harvesting of marine
food resources and explain how that regulation or law helps to manage marine species.
(d) The oceans of the world are often referred to as a commons. Give an example of one other such commons,
explain how human activities affect that commons, and suggest one practical method for managing that
commons.
STOP
END OF EXAM
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5
AP® Environmental Science
2007 Free-Response Questions
The College Board: Connecting Students to College Success
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the association is composed of more than 5,000 schools, colleges, universities, and other
educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and
3,500 colleges through major programs and services in college admissions, guidance, assessment, financial aid, enrollment, and
teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®, and the Advanced Placement
Program® (AP®). The College Board is committed to the principles of excellence and equity, and that commitment is embodied
in all of its programs, services, activities, and concerns.
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acorn logo are registered trademarks of the College Board. PSAT/NMSQT is a registered trademark of the College Board and
National Merit Scholarship Corporation.
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2007 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time—90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the Fremont Examiner article below and answer the questions that follow.
(a) Identify ONE component of the sewage that is targeted for removal by primary treatment and ONE
component of the sewage that is targeted for removal by secondary treatment.
(b) For EACH of the pollutants that you identified in part (a), describe how the pollutant is removed in the
treatment process.
(c) Explain how sewage treatment plants create the solid waste problem that Dr. Goodwin mentioned in the
article.
(d) Two common methods of disposing of solid waste from sewage treatment plants are transporting it to a
landfill or spreading it onto agricultural lands. Describe an environmental problem associated with EACH of
these methods.
(e) The final step in sewage treatment is disinfection. Identify ONE pollutant that is targeted during disinfection
and identify ONE commonly used method of disinfection.
(f) Identify ONE United States federal law that requires monitoring the quality of the treated sewage that is
discharged into the Fremont River.
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2007 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. The Cobb family of Fremont is looking at ways to decrease their home water and energy usage. Their current
electric hot-water heater raises the water temperature to 140°F, which requires 0.20 kWh/gallon at a cost of
$0.10/kWh. Each person in the family of four showers once a day for an average of 10 minutes per shower.
The shower has a flow rate of 5.0 gallons per minute.
(a) Calculate the following. Be sure to show all your work and include units with your answers.
(i) The total amount of water that the family uses per year for taking showers
(ii) The annual cost of the electricity for the family showers, assuming that 2.5 gallons per minute of the
water used is from the hot-water heater
(b) The family is considering replacing their current hot-water heater with a new energy-efficient hot-water
heater that costs $1,000 and uses half the energy that their current hot-water heater uses. How many days
would it take for the new hot-water heater to recover the $1,000 initial cost?
(c) Describe TWO practical measures that the family could take that would reduce their overall water use at
home.
(d) Describe TWO conservation measures (other than reducing hot water use) that the family could take to
reduce the total amount of energy that they use at home.
3. In the mid 1970s, Sherwood Rowland and Mario Molina predicted a thinning of the stratospheric ozone layer
over Antarctica. The thinning was confirmed in the late twentieth century and has continued into the twenty-first
century.
(a) Identify the class of chemical compounds that is primarily responsible for the thinning of the stratospheric
ozone layer and describe TWO major uses for which these chemicals were manufactured.
(b) Describe how the chemical compounds that you identified in part (a) destroy stratospheric ozone molecules.
You may include chemical equations as part of your answer.
(c) Identify the major environmental consequence of the depletion of stratospheric ozone and describe TWO
effects on ecosystems and/or human health that can result.
(d) Ozone formed at ground level is a harmful pollutant. Describe TWO effects that ground-level ozone can
have on ecosystems and/or human health.
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2007 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Some scientists estimate that by 2025 over 60 percent of the global human population will live in urban areas.
Urban residents experience a variety of problems related to the physical environment.
(a) Describe how the temperature of urban areas like Atlanta, Philadelphia, and Chicago differs from that of
surrounding rural areas.
(b) Identify and describe TWO differences between urban and surrounding rural areas that contribute to the
temperature difference between them.
(c) Urban areas typically have levels of air pollution that are significantly higher than those found in
surrounding rural areas. Identify a characteristic of the urban microclimate that leads to higher levels of air
pollution and describe how that characteristic contributes to the increase.
(d) Identify and describe TWO actions that local governments in urban areas could take to reduce outdoor air
pollution.
(e) Identify and describe TWO ways in which the local hydrologic cycle of urban areas differs from that of
nearby rural areas.
STOP
END OF EXAM
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AP® Environmental Science
2008 Free-Response Questions
The College Board: Connecting Students to College Success
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the association is composed of more than 5,000 schools, colleges, universities, and other
educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and
3,500 colleges through major programs and services in college admissions, guidance, assessment, financial aid, enrollment, and
teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT®, and the Advanced Placement
Program® (AP®). The College Board is committed to the principles of excellence and equity, and that commitment is embodied
in all of its programs, services, activities, and concerns.
© 2008 The College Board. All rights reserved. College Board, Advanced Placement Program, AP, AP Central, SAT, and the
acorn logo are registered trademarks of the College Board. PSAT/NMSQT is a registered trademark of the College Board and
National Merit Scholarship Corporation.
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the article below and answer the questions that follow.
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(a) Calculate the number of acres required to produce 1,000 gallons of oil in one year from
(i) microalgae
(ii) soybeans
(b) Describe TWO environmental advantages that biodiesel production from microalgae offers over biodiesel
production from the other crops listed in the table.
(c) Explain why burning biodiesel fuel has a different impact on atmospheric CO2 concentrations than does
burning fossil fuels.
(d) Discuss TWO benefits, other than those related to atmospheric impacts, of increased reliance on biodiesel
fuels over the next 50 years.
(e) Describe TWO economic or societal problems associated with producing fuel from corn.
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. The city of Fremont operates a municipal solid-waste landfill. As represented in the diagram above, the annual
precipitation in Fremont is 200 mm/year: 50 percent of this water infiltrates through the landfill cover soil into
the waste, and 50 percent drains off the landfill. A drainage system withdraws 90 percent of the leachate
generated within the landfill for treatment. The rest of the leachate travels through the bottom liner of the landfill
into the surrounding soil. Most of the cadmium disposed of in the landfill remains in the landfill; the leachate
withdrawn from the landfill by the drainage system has an average cadmium concentration of 2.0 g/m3. Pumped
to a treatment station, the leachate is treated at a cost of $10/m3.
(a) Calculate the volume, in m3, of each of the following:
(i) The water infiltrated through the landfill per year
(ii) The leachate that is treated per year
(b) Given that the cadmium concentration in the water draining from the landfill is 2.0 g/m3, calculate the mass,
in kg, of cadmium that is released into the surrounding soil per year.
(c) What is the annual cost of treating the leachate from the drainage system?
(d) Discuss TWO viable methods for reducing the amount of cadmium entering the municipal waste input.
(e) Explain a shortcoming of ONE of the methods that you identified in part (d).
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. For decades, forest fires in the United States have been suppressed. In 2003 legislation was passed under the
Healthy Forests Initiative (HFI) in response to the record-breaking wildfires that had occurred in the early 2000s.
Some environmental and conservation groups fear that negative impacts could result if timber companies are
encouraged to harvest medium- and large-size trees in federally owned forests while clearing away the smaller
trees and underbrush.
(a) Identify TWO characteristics of forests that develop when fires are suppressed, and explain why the practice
of fire suppression does not reduce, but actually increases, the risk of intense and extensive forest fires.
(b) The effects of the HFI are expected to extend beyond fire reduction. Excluding fire reduction, describe ONE
positive and ONE negative effect likely to result from the implementation of the provisions of the HFI.
(c) Describe TWO ecosystem services provided for humans by forests. Explain how clear-cutting would affect
each ecosystem service you describe.
(d) Identify a specific type of plant community or biome (other than a forest) that is naturally maintained by fire.
Explain how the fire maintains the community or biome.
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Answer the following regarding world human population.
(a) Create a graph of the data from table 1 below on the axes provided.
Table 1:
Worldwide
Total Fertility
Rate (TFR)
Year
TFR
1950
5.0
1960
4.9
1970
4.7
1980
3.7
1990
3.4
2000
3.0
(b) Identify and discuss TWO of the causes for the trend in the worldwide TFR that you graphed in part (a).
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2008 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
Table 2: Population Data for Selected Nations (2005)
Country
TFR
Crude
Birth
Rate*
Crude
Death
Rate*
Infant
Mortality
Rate*
(U.S. dollars)
Per Capita
Income
China
1.6
12
7
27
6,500
Japan
1.3
9
8
2.8
31,400
Kenya
5.9
43
19
100
1,000
United
States
2.0
14
8
6.7
42,000
* rates are per thousand per year
(c) Consider the data in table 2 above. Identify and discuss TWO economic or societal factors that account for
the difference between the TFR of Kenya and that of the United States.
(d) Describe TWO human activities related to the rapidly growing world population that are having an impact
on Earth’s biodiversity.
STOP
END OF EXAM
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-7-
AP® Environmental Science
2009 Free-Response Questions
The College Board
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the association is composed of more than 5,600 schools, colleges, universities and other
educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools and
3,800 colleges through major programs and services in college readiness, college admissions, guidance, assessment, financial aid,
enrollment, and teaching and learning. Among its best-known programs are the SAT®, the PSAT/NMSQT® and the Advanced
Placement Program® (AP®). The College Board is committed to the principles of excellence and equity, and that commitment is
embodied in all of its programs, services, activities and concerns.
© 2009 The College Board. All rights reserved. College Board, Advanced Placement Program, AP, AP Central, SAT, and the
acorn logo are registered trademarks of the College Board. PSAT/NMSQT is a registered trademark of the College Board and
National Merit Scholarship Corporation.
Permission to use copyrighted College Board materials may be requested online at:
www.collegeboard.com/inquiry/cbpermit.html.
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AP Central is the official online home for the AP Program: apcentral.collegeboard.com.
2009 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the article below from the Fremont Free Press and answer the questions that follow.
(a) Support Councilwoman Smith’s statement that nitrogen-based fertilizers cause other environmental
problems by describing one such problem.
(b) Identify a nitrogen-containing primary pollutant that contributes to the formation of photochemical smog.
Describe how that primary pollutant forms and explain why Councilman Budd was wrong.
(c) Identify one secondary pollutant that is a component of photochemical smog and describe the following.
(i) How the secondary pollutant forms
(ii) ONE human health effect of the pollutant
(iii) ONE environmental effect of the pollutant
(d) Earth’s natural nitrogen cycle occurs in several steps. Describe one chemical transformation that occurs in
the natural nitrogen cycle and discuss the importance of that transformation to an ecosystem.
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2009 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. Anaerobic methane digesters have been used for many years to reduce energy costs on farms throughout Europe
and on some large farms in the United States. The digesters operate by using anaerobic bacteria to break down
animal waste. During the process, which typically uses a tank heated to about 100°F (38ÁC) to speed the
reactions, raw manure is broken down and methane is produced. The methane can then be used to generate
electricity or produce heat.
For a certain dairy farm with 500 cows, the cost of installing a digester is approximately $400,000. Assume that
the farm uses 800,000 kilowatt-hours (kWh) of electricity each year at a cost of $0.10 per kWh. The waste from
a single cow can produce 3.0 kWh of electricity each day.
(a) Describe the steps by which methane produced in the digester can be used to generate electricity.
(b) Discuss TWO environmental benefits that may result from the installation of an anaerobic methane digester.
(c) Assuming that the cost of electricity remains constant and the farmer starts using the manure from the cows
in an anaerobic digester to produce electricity on the farm, calculate:
(i) The number of kWh of electricity that can be produced in one year
(ii) The amount of money the farmer can save in one year, NOT counting the installation cost of the
digester. (You may round your answer to the nearest $1,000.)
(iii) The amount of time, in years, that it will take to recover the cost of installing an anaerobic digester on
the farm. (You may round your answer to the nearest whole number of years.)
(d) Calculate the minimum number of cows the farm would need to produce 800,000 kWh of electricity
per year.
3. The Colorado River flows from the Colorado Rockies to the Gulf of California. The primary source of Colorado
River water is melting Rocky Mountain snowpack. Once the river descends from the Rockies, it flows through a
landscape that is dominated by desert. Colorado River water carries a high load of sediment.
(a) Multiple dams have been erected along the Colorado River. Identify TWO benefits other than agriculture
and recreation that people derive from that system of dams.
(b) Discuss TWO potential environmental consequences of damming a major river.
(c) Competition for access to Colorado River water has increased dramatically due to increased population size
and intensive agricultural use. Describe TWO conservation strategies for reducing agricultural water
consumption.
(d) Identify TWO possible environmental consequences of climate change on the hydrology of the Colorado
River system.
(e) In addition to impacts on the Colorado River system, climate change is impacting the hydrology of coastal
ecosystems. Identify and describe TWO possible consequences of climate change on coastal ecosystems.
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2009 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. The major issues in modern agriculture include the use of genetically modified (GM) crops and the
implementation of sustainable agricultural practices. The following graph shows the increase in the
use of GM crops in both developing and industrialized countries from 1995 to 2004.
(a) Reply to the following questions based on the data in the graph above.
(i) Calculate the increase in the area of land used for growing GM crops in developing countries from
1999 to 2003. Express your answer as a percentage of the 1999 value.
(ii) Calculate the annual rate of increase in land area used for growing GM crops in industrialized countries
from 1997 to 1999.
(iii) Using the rate you calculated in part (ii), project the area of land that would have been expected to be
used for GM crops in industrialized countries in 2004.
(iv) Identify one likely cause for the difference between the projected land area for GM crops in
industrialized countries in 2004 and the actual land area for GM crops in industrialized countries in
2004.
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2009 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(b) Describe one environmental advantage and one environmental disadvantage of using GM crops.
(c) Describe one economic advantage and one economic disadvantage of using GM crops.
(d) A healthy soil ecosystem is of primary importance in sustainable agriculture. Describe TWO viable
agricultural practices that farmers can use to maintain or improve soil quality.
(e) Identify and describe one environmental advantage and one economic advantage of consuming locally
grown produce.
STOP
END OF EXAM
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AP® Environmental Science
2010 Free-Response Questions
The College Board
The College Board is a not-for-profit membership association whose mission is to connect students to college success and
opportunity. Founded in 1900, the College Board is composed of more than 5,700 schools, colleges, universities and other
educational organizations. Each year, the College Board serves seven million students and their parents, 23,000 high schools, and
3,800 colleges through major programs and services in college readiness, college admission, guidance, assessment, financial aid
and enrollment. Among its widely recognized programs are the SAT®, the PSAT/NMSQT®, the Advanced Placement Program®
(AP®), SpringBoard® and ACCUPLACER®. The College Board is committed to the principles of excellence and equity, and that
commitment is embodied in all of its programs, services, activities and concerns.
© 2010 The College Board. College Board, ACCUPLACER, Advanced Placement Program, AP, AP Central, SAT, SpringBoard
and the acorn logo are registered trademarks of the College Board. Admitted Class Evaluation Service is a trademark owned by
the College Board. PSAT/NMSQT is a registered trademark of the College Board and National Merit Scholarship Corporation.
All other products and services may be trademarks of their respective owners. Permission to use copyrighted College Board
materials may be requested online at: www.collegeboard.com/inquiry/cbpermit.html.
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2010 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the following article from the Fremont Gazette and answer the questions that follow.
(a) Choose any ONE of the three pollutants mentioned above and respond to each of the following.
(i) Describe one specific source, other than the local chemical plants, for the toxic pollutant you chose.
(ii) Describe how the pollutant you chose enters the human body and one specific effect it can have on
human health.
(iii) Describe TWO specific steps, other than an outright ban, that a city or nation can take to reduce the
threat posed by this pollutant.
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2010 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(b) Give one reason why Dr. Egguen is correct in asserting that children are particularly susceptible to toxic
pollutants.
(c) An important contributor to global climate change is the release of CO2 from the rapidly increasing number
of coal-burning power plants in China. Assume that the coal burned at these plants to provide the power to
manufacture a single MP3 player releases 40 kg of CO2 and that it costs $0.75 to capture 1 kg of CO2 and
keep it from entering the atmosphere. Determine the cost, in dollars, to capture the total amount of CO2
released from manufacturing one MP3 player.
(d) Coal-burning power plants also release other pollutants, including nitrogen oxides (NOx ), sulfur oxides
(SOx ), and particulates. Select one of these pollutants and identify one technology that can be used to
remove it from the waste stream of coal-burning power plants.
(e) Discuss TWO reasons why a multinational company would choose to build a manufacturing facility in India
and/or China rather than in the United States or Europe.
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2010 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. Termites are social insects that are essential decomposers in tropical rain forest ecosystems. Termites may
account for up to 95 percent of insect biomass in tropical rain forests. Termites consume vast amounts of dead
and decomposing plant material, thanks to the work of mutualistic cellulose-digesting microorganisms that
inhabit their guts. In addition to their roles as important decomposers, termites digest plant materials and directly
contribute to carbon dioxide and methane emissions into the atmosphere. It is likely that, like many insect
species, termites and their symbionts may be sensitive to changes in their microclimate caused by global climate
change, especially with regard to temperature and humidity.
Temperature
Relative Humidity
50%
70%
90%
20°C
0.04
0.05
0.05
25°C
0.05
0.07
0.10
30°C
0.12
0.13
0.27
35°C
0.09
0.13
0.15
40°C
0.00
0.00
0.00
(a) Respond to the following using the data in the table above, which gives the rate of wood consumption by
termites, in mg per day per termite, under various temperature and relative humidity conditions. Under
optimal conditions, the emission rate of methane by termites is approximately 70 kilograms of CH4 per year
per 1,000 termites.
(i) According to the data, what are the optimal temperature and relative humidity for termite activity?
(ii) Given a density of 4.5 × 107 termites per hectare and optimal conditions, calculate the annual amount
of methane emitted, in kilograms, by the termites inhabiting a 2,000-hectare tropical rain forest.
(iii) Suppose the temperature increases to 35°C and the relative humidity decreases to 50 percent. Using the
data provided, determine the amount of methane, in kilograms, that would be emitted by the termites in
the 2,000-hectare tropical rain forest.
(iv) Explain why the population size of termites is also affected by temperature and humidity.
(b) It has been observed that soon after a tropical rain forest is cleared, termite density increases to an estimated
6.8 × 107 termites per hectare. Thereafter, the termite population size decreases dramatically.
(i) What is the most likely reason that the density of the termites increases when a tropical rain forest is
cleared?
(ii) Why do the termite populations eventually decrease dramatically?
(c) Describe one way, other than changes in termite activity, that tropical rain forest destruction contributes to
anthropogenic climate change.
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2010 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. The zebra mussel, a mollusk native to Eurasia, was first discovered in the Great Lakes of North America in
1988. Zebra mussels attach to solid substrates and are filter feeders. Adult zebra mussels can survive for several
days or even weeks out of water if the temperature and humidity are favorable. An adult female zebra mussel
can produce as many as one million eggs per year. The recent range of occurrence of zebra mussels in the
United States is indicated by shading in the map above.
(a) Why are zebra mussels located primarily in areas in the eastern United States rather than in the western
United States?
(b) How are zebra mussels introduced into isolated lakes? Describe one viable method for preventing the spread
of zebra mussels into isolated lakes.
(c) Identify and explain one impact that zebra mussels can have on aquatic ecosystems.
(d) Identify another invasive species, either terrestrial or aquatic, and describe one negative impact it has had.
(e) One strategy for controlling an invasive species has been to introduce another nonnative species to control it;
this strategy can often have unintended results. Give a specific example of the use of this strategy and
discuss a negative impact of introducing a nonnative species to control an invasive species.
(f) Discuss TWO specific characteristics of invasive species that enable them to thrive in new environments.
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-5-
2010 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Scientific evidence shows a direct relationship between sea level and the global mean atmospheric temperature
at Earth’s surface. Increases in the global mean atmospheric temperature during the past century have been
accompanied by a gradual increase in sea level; currently the average rate of increase in sea level is 3.0 mm/yr.
Additional increases in sea level are expected during the next century as global mean atmospheric temperatures
continue to rise. These increases in sea level will affect coastal ecosystems as well as human activity along
coastal margins.
(a) Based on the rate cited above, calculate the expected increase in sea level, in meters, during the next
50 years.
(b) Identify TWO phenomena that result from an increase in global mean atmospheric temperature and that
contribute to increases in sea level. For each phenomenon that you identify, explain how it causes sea level
to increase.
(c) Describe TWO environmental impacts that increasing sea level will have on an estuarine ecosystem such
as those in the Mississippi Delta, Chesapeake Bay, and San Francisco Bay.
(d) Although sea level has been rising for over a century, human populations in coastal areas have increased
dramatically during this period.
(i) Describe one negative economic impact that an increase in sea level will have on people who live
along a coastline.
(ii) Describe TWO viable strategies that governments could use to discourage people from moving to
coastal areas.
STOP
END OF EXAM
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AP® Environmental Science
2011 Free-Response Questions
About the College Board
The College Board is a mission-driven not-for-profit organization that connects students to college success and opportunity.
Founded in 1900, the College Board was created to expand access to higher education. Today, the membership association is
made up of more than 5,900 of the world’s leading educational institutions and is dedicated to promoting excellence and equity in
education. Each year, the College Board helps more than seven million students prepare for a successful transition to college
through programs and services in college readiness and college success — including the SAT® and the Advanced
Placement Program®. The organization also serves the education community through research and advocacy on behalf of
students, educators and schools.
© 2011 The College Board. College Board, Advanced Placement Program, AP, AP Central, SAT and the acorn logo are registered
trademarks of the College Board. Admitted Class Evaluation Service and inspiring minds are trademarks owned by the College
Board. All other products and services may be trademarks of their respective owners. Visit the College Board on the Web:
www.collegeboard.org. Permission to use copyrighted College Board materials may be requested online at:
www.collegeboard.org/inquiry/cbpermit.html.
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AP Central is the official online home for the AP Program: apcentral.collegeboard.com.
2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in the pink booklet. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the following article from the Fremont Inquirer and answer the questions that follow.
(a) As mentioned in the article, there are several possible explanations for the increase in mountain pine beetles.
(i) Provide one reason why fire-suppression policies lead to increased beetle activity.
(ii) Reduced winter mortality of beetle larvae is likely a consequence of global climate change. Describe
TWO ways that the activities of the beetles might enhance climate change.
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2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(b) The widespread death of trees leads to a series of changes in a forest ecosystem. Identify TWO physical
changes that occur in the forest ecosystem as the result of the death of mature trees. For each physical
change you identify, describe an impact of that change on the forest ecosystem.
(c) As the article states, the number of managed honeybee colonies has dropped significantly over the past few
decades. Describe TWO specific economic consequences of the collapse of the managed honeybee colonies.
(d) Pollination by native insects is considered an ecosystem service. Identify a different ecosystem service and
explain how that service benefits human society.
2. Coral reefs are produced when corals acquire calcium ions (Ca2+) and carbonate ions (CO32−) from seawater and
deposit solid CaCO3 to form their exoskeletons. Scientists are concerned that relatively rapid decreases in ocean
water pH will hinder the deposition of CaCO3. The graph above shows the amount of CO2 dissolved in ocean
water and ocean water pH (shown in parentheses) since 1850 and the predicted changes through 2100.
(a) Explain how an increase in the amount of dissolved CO2 in ocean water results in a decrease in the pH of
ocean water.
(b) Explain why the movement of carbon into the ocean has been increasing since 1850.
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2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(c) In order to model the effects of ocean acidification on coral reefs, some simplifying assumptions can be
made. Use the assumptions in the table below to perform the calculations that follow.
Assume that the total global area of corals growing in reefs is 2.5 × 1011 m2.
Assume that corals grow only vertically and that the average vertical growth rate of corals is 3 mm/year.
Assume that the average density of CaCO3 in corals is 2 × 103 kg/m3.
(i) Calculate the current annual global increase in volume, in m3, of CaCO3 in coral reefs. Show all steps
in your calculation.
(ii) Calculate the current annual global increase in mass, in kg, of CaCO3 in coral reefs. Show all steps in
your calculation.
(iii) Because of ocean acidification, it is expected that in 2050 the mass of CaCO3 deposited annually in
coral reefs will be 20 percent less than is deposited currently. Calculate how much less CaCO3 , in kg,
is expected to be deposited in 2050 than would be deposited if ocean water pH were to remain at its
current value.
(d) Identify and describe one likely negative environmental impact of the loss of coral reefs.
(e) Identify one environmental problem (other than one due to ocean acidification or loss of coral reefs) that
affects marine ecosystems on a global scale.
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2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Shown above is a graph of the gross domestic product (GDP) per capita versus the annual electrical energy
consumption per capita for nine countries in 2009.
(a) Iceland’s position on the graph is due in part to its access to geothermal energy sources. Describe how
electricity is generated from a geothermal source.
(b) Despite its low GDP per capita and low annual electrical energy consumption per capita, China has become
the world’s largest emitter of CO2 . Explain this apparent contradiction.
(c) In addition to contributing to increased atmospheric CO2 concentrations, China is facing other air pollution
issues related to the generation of electricity. Identify one such issue and describe the impact it has on
human health.
(d) Two countries shown on the graph have developed domestic energy sources: sugarcane in Brazil and tar
sands in western Canada.
(i) Choose EITHER sugarcane or tar sands, then briefly describe the process of fuel production from that
energy source.
(ii) Describe TWO disadvantages of using the energy source that you chose in part (d)(i).
(iii) Which of the two energy sources is more sustainable? Justify your answer with an explanation.
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2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. As the world’s population increases and availability of new arable land decreases, providing sufficient food for
the world’s human population is becoming increasingly difficult. The table below shows the area of land needed
to feed the world’s population from 1900 projected to the year 2060.
Year
1900
1940
1980
2020
2060
Land Area Needed
(billion hectares)
0.40
0.60
1.25
2.50
4.75
(a) On the graph below, plot the data from the table above and draw a smooth curve.
(b) Assume that the maximum arable land area on Earth is 4.00 billion hectares. Using the smooth curve that
you created above, determine the year in which the human population is likely to run out of arable land for
agriculture.
(c) Soil quality is a critical factor in agriculture. Identify TWO physical and/or chemical properties of soils and
describe the role of each property in determining soil quality.
(d) Describe TWO viable strategies for reducing the amount of land needed for agriculture.
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2011 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
(e) One problem that can result from agriculture is soil salinization.
(i) Describe how salinization occurs.
(ii) Describe one method to prevent or remediate soil salinization.
STOP
END OF EXAM
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AP® Environmental Science
2012 Free-Response Questions
About the College Board
The College Board is a mission-driven not-for-profit organization that connects students to college success and opportunity.
Founded in 1900, the College Board was created to expand access to higher education. Today, the membership association is
made up of more than 5,900 of the world’s leading educational institutions and is dedicated to promoting excellence and equity in
education. Each year, the College Board helps more than seven million students prepare for a successful transition to college
through programs and services in college readiness and college success — including the SAT® and the Advanced
Placement Program®. The organization also serves the education community through research and advocacy on behalf of
students, educators, and schools.
© 2012 The College Board. College Board, Advanced Placement Program, AP, AP Central, SAT, and the acorn logo are registered
trademarks of the College Board. Admitted Class Evaluation Service and inspiring minds are trademarks owned by the College
Board. All other products and services may be trademarks of their respective owners. Visit the College Board on the Web:
www.collegeboard.org. Permission to use copyrighted College Board materials may be requested online at:
www.collegeboard.org/inquiry/cbpermit.html.
Visit the College Board on the Web: www.collegeboard.org.
AP Central is the official online home for the AP Program: apcentral.collegeboard.org.
2012 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this book. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the following article from the Fremont Gazette and answer the questions that follow.
(a) Identify and describe TWO water-related environmental problems associated with fracking.
(b) Natural gas is considered to be a better fossil fuel for the environment than coal is. Discuss TWO
environmental benefits of using natural gas as a fuel compared to using coal.
(c) Describe TWO environmental drawbacks, not related to water use, of using the fracking process to extract
natural gas from shale.
(d) Describe one economic benefit to society of using fracking to obtain natural gas from shale.
(e) Nuclear power is an alternative to using natural gas or coal as a fuel for generating electricity. However,
there are also problems associated with nuclear power plants. Describe TWO negative environmental
impacts associated with nuclear power.
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2012 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. The Fremont School District uses oil to heat school buildings. Go Green! is a new project the district will
implement. The superintendent has declared that the district will dedicate itself to reducing its carbon footprint.
In addition to taking serious energy-conservation measures, the district is planning to help offset its carbon
dioxide emissions by raising money to help conserve a portion of a large tract of forest land adjacent to the high
school campus.
(a) Describe one alternative energy source that would reduce the carbon footprint of the school district. Discuss
one environmental benefit (other than reduced CO2 emissions) and one environmental drawback of using the
alternative source instead of fuel oil.
(b) Identify TWO ecological benefits provided by intact forest ecosystems (other than reducing CO2 levels in
the atmosphere).
(c) Use the assumptions below to answer the questions that follow. For each calculation, show all work.
The biomass of the forest increases at an annual rate of 2.7 × 105 kg/ha.
The forest biomass is 50 percent carbon by mass.
Each year the district uses 3.0 × 105 gallons of fuel oil for heating and hot water.
10 kg of CO2 is produced when 1 gallon of fuel oil is burned.
1.0 kg of CO2 contains 0.27 kg of carbon.
The cost of putting 1 ha of the forest into conservancy is $12,000.
(i) Calculate the mass of carbon, in kg, that is accumulated and stored in 1.0 ha of forest in one year.
(ii) Calculate the mass of carbon, in kg, that is emitted by the school as a result of its fuel-oil consumption
in one year.
(iii) Calculate the number of hectares of forest the school district needs to conserve in order to offset the
carbon released in one year by the school burning its fuel oil.
(iv) Calculate the amount of money the school district must raise for the conservation project.
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2012 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. The active ingredients in many pesticides are chemical compounds that kill organisms such as insects, molds,
and weeds. Proponents claim that the use of pesticides improves crop yields and thus protects land and soil by
reducing the conversion of forests and wetlands to cropland. Opponents of pesticide use claim that pesticides
degrade water and soil quality and that other modern agricultural techniques and practices are responsible for the
improved crop yields in recent years.
(a) Design a laboratory experiment to determine whether or not a new pesticide (product X) is toxic to
minnows, a type of small fish. For the experiment you design, be sure to do all of the following.
(i) State the hypothesis.
(ii) Describe the method you would use to test your hypothesis.
(iii) Identify the control.
(iv) Identify the dependent variable.
(b) Describe experimental results that would lead you to reject your hypothesis in part (a)(i). (Be specific.)
(c) One strategy for dealing with agricultural pests is integrated pest management (IPM).
(i) Describe IPM. As part of your description, include TWO specific pest-control approaches that are part
of IPM.
(ii) Identify one environmental benefit of using IPM.
(d) Describe TWO agricultural practices, other than those involving pest control, that increase crop yields.
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2012 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Wetlands were once considered to be wastelands. Over 50 percent of the United States original wetlands have
been destroyed.
(a) Describe TWO characteristics that are used by scientists to define an area as a wetland.
(b) Wetlands are highly productive ecosystems with complex food webs.
(i) Complete the diagram of the wetland food web below by drawing arrows that show the direction of
energy flow.
(ii) Explain why it takes many hectares of wetland to support a pair of eagles.
(c) Describe TWO economic benefits (other than those related to water quality) that wetlands provide.
(d) Describe one specific human activity that degrades wetlands.
(e) Wastewater treatment plants perform some of the same water-quality improvement functions that natural
wetlands perform. Explain how wetlands perform the equivalent of
(i) primary treatment, and
(ii) secondary treatment.
STOP
END OF EXAM
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AP® Environmental Science
2013 Free-Response Questions
About the College Board
The College Board is a mission-driven not-for-profit organization that connects students to college success and opportunity.
Founded in 1900, the College Board was created to expand access to higher education. Today, the membership association is
made up of more than 6,000 of the world’s leading educational institutions and is dedicated to promoting excellence and equity
in education. Each year, the College Board helps more than seven million students prepare for a successful transition to college
through programs and services in college readiness and college success — including the SAT® and the Advanced
Placement Program®. The organization also serves the education community through research and advocacy on behalf of
students, educators, and schools.
© 2013 The College Board. College Board, Advanced Placement Program, AP, AP Central, SAT, and the acorn logo are
registered trademarks of the College Board. Admitted Class Evaluation Service and inspiring minds are trademarks owned by
the College Board. All other products and services may be trademarks of their respective owners. Visit the College Board on
the Web: www.collegeboard.org. Permission to use copyrighted College Board materials may be requested online
at: www.collegeboard.org/inquiry/cbpermit.html.
Visit the College Board on the Web: www.collegeboard.org.
AP Central is the official online home for the AP Program: apcentral.collegeboard.org.
2013 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this book. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. (a) Identify TWO human activities that alter the natural flow of sediments into Gulf Coast ecosystems. Explain
how each of the activities alters the flow of sediments.
(b) Dr. James says that it is important to restore sediments. Describe TWO ways that the loss of natural
sediment harms Gulf Coast wetland ecosystems.
(c) Dr. James also indicates that it is necessary to limit fertilizer runoff into the Mississippi River.
i. Describe TWO environmental impacts on the marine ecosystem that are caused by fertilizer
when it flows into the Gulf of Mexico.
ii. What are TWO economic consequences that result from the flow of fertilizer into the
Gulf of Mexico?
iii. Describe ONE strategy, other than reducing the use of fertilizer, that can be employed to
reduce the flow of nutrients into the Mississippi River.
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2013 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. Battery electric vehicles (BEVs) have been introduced to consumers as an alternative way to reduce the
environmental effects caused by use of internal-combustion engine (ICE) vehicles. A comparison of both
vehicle types can help determine whether the use of BEVs would be beneficial in the future. Where calculations
are required, show your work.
(a) Identify THREE strategies that the federal government could implement to encourage the use of BEVs.
(b) Assume that the fuel efficiency of the ICE vehicle is 25 miles per gallon (mpg) and that gasoline costs
$3.75 per gallon (gal). Calculate the cost of gasoline per mile.
(c) The charger supplies energy to the BEV battery at an average rate of 4.0 kilowatts (kW) and fully charges
the BEV battery in 7.0 hours. The car will run for 100 miles on a full charge. The cost of electricity is
$0.11 per kilowatt-hour (kWh).
i. Calculate the cost of the electricity to fully charge the battery. Assume that the battery is not charged
to begin with.
ii. Calculate the cost of electricity per mile to drive the BEV.
When it is driven 100 miles, the ICE vehicle contributes 72.8 pounds (lb) of CO 2 from the burning of the
gasoline. The drilling, refining, and transportation costs of getting the gasoline to the gas station add an
additional 17.7 lb of CO2 per 100 miles. The BEV does not emit any CO 2 itself, but the extraction,
transportation, and combustion of the coal that produced the electricity at the power plant add 63.6 lb of CO 2 for
the same 100 miles.
(d) Calculate the difference in the amount of CO2 that would enter the atmosphere if both cars were driven
100 miles.
(e) Describe TWO economic impacts (excluding costs related to climate change resulting from CO2 emissions
or the cost of gasoline at the pump) that result from an increased number of BEVs on the road.
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2013 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Ozone O3 is an atmospheric trace gas that occurs naturally in the stratosphere. It is also formed as a
consequence of human activity in the troposphere, immediately above Earth’s surface. The location of ozone
in the atmosphere determines whether the gas protects or damages the environment.
(a) Identify the type of solar radiation that is absorbed by stratospheric ozone, and describe one human health
benefit that results from the absorption of this solar energy.
(b) The absorption of solar energy by stratospheric ozone causes ozone molecules to undergo chemical
decomposition and formation. Describe the chemical processes that lead to this natural balance between
decomposition and formation of stratospheric ozone (you may use chemical equations in your answer).
(c) The Montreal Protocol of 1987 provided a global framework to phase out chlorofluorocarbon (CFC)
production and use. Although the Montreal Protocol has led to a dramatic decrease in CFCs released into
the atmosphere, stratospheric ozone destruction has decreased only slightly.
i. Explain the process by which CFCs lead to the destruction of stratospheric ozone. (You may use
chemical equations in your answer.)
ii. Explain why the rapid decrease in CFC emissions has not led to a similarly rapid decrease in the
destruction of stratospheric ozone.
(d) Identify a human activity that leads to the formation of tropospheric ozone as a secondary pollutant and
explain why tropospheric ozone levels peak in the daytime.
(e) Identify one negative ecological impact and one negative human health impact that result from the
formation of tropospheric ozone.
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2013 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Biological diversity, or biodiversity, has become a topic of great concern among conservationists. Biodiversity is
often used by scientists and policy makers to help determine the health of ecosystems.
(a) Describe TWO characteristics shared by ecosystems that have high biodiversity.
(b) Identify TWO specific human activities that result in a loss of biodiversity, and explain how each activity
lowers biodiversity.
(c) For each human activity you discussed in (b), propose a practical strategy (other than simply banning the
activity) to reduce the loss of biodiversity.
(d) Describe ONE naturally occurring factor that could lead to a loss of biodiversity.
(e) Describe TWO ecological benefits that greater biodiversity provides.
STOP
END OF EXAM
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AP Environmental Science
2014 Free-Response Questions
®
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are registered trademarks of the College Board.
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2014 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this book. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the article below and answer the questions that follow.
(a) State whether you agree or disagree with each of the following remarks made by Dr. Kull. For each remark,
provide one justification for your position.
(i) “Nuclear power plants produce no dangerous solid waste.”
(ii) “Using nuclear power avoids the release of greenhouse gases.”
(b) If the plan for a nuclear power plant in Fremont is approved, it will take several years for the plant to
be built. Describe TWO environmental problems that could result from the construction of the plant
(i.e., prior to operation).
(c) Suppose that the nuclear power plant is constructed on the Fremont River site.
(i) Identify the most likely pollution threat that the plant will pose to the Fremont River as a result of the
plant’s normal daily operation.
(ii) Discuss one potential ecological consequence of the pollution threat that you identified in part (i).
(iii) Identify a system often used in nuclear power plants to reduce the pollution you identified in part (i).
(d) Describe TWO specific steps that Fremont residents and/or businesses could take to reduce the use of
electricity.
(e) Identify a specific nuclear power plant at which a major accident has occurred. Explain one environmental
consequence (other than effects on human health) of a nuclear power plant accident.
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2014 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. Like many communities, Fremont has a combined sewer system that collects both sewage and storm water.
When storm water runs into storm drains that connect to the city’s sanitary sewer system, the storm water and
sewage flow together to the Fremont Wastewater Treatment Plant (FWTP). During a major storm event,
however, the combined volume of storm water and sewage may exceed the plant’s capacity, and the overflow
bypasses the FWTP. The untreated overflow is discharged into Fremont Creek along with the treated waste.
Recently parts of Fremont received 5 cm of rain in 60 minutes. The storm caused widespread flooding in the
northeast section of town. Especially hard hit was the Shoppes at Fremont shopping center.
Use the data from the table below to answer the questions that follow. Show all calculations.
Fremont Water Data
The shopping center’s parking lot is 200 meters long and 100 meters wide.
2
Fremont has an area of 10 km .
Impervious surfaces cover 20 percent of Fremont’s area.
3
The FWTP typically treats 5,000 m of domestic sewage per day.
3
The FWTP has the capacity to treat 10,000 m of combined sewage and storm water
per day.
(a) Identify TWO specific pollutants in storm-water runoff that degrade the quality of surface water.
3
(b) Calculate the volume of water (in m ) that runs off the Shoppes at Fremont parking lot after a 5 cm rainfall
event. Assume that all the water that falls on the parking lot runs off.
3
(c) Calculate the volume of storm-water runoff (in m ) generated in all of Fremont by the 5 cm rainfall event.
Assume that only the impervious surfaces generate runoff.
(d) Assume that all the runoff that you calculated in part (c) is captured by the storm sewers in one day.
3
Calculate the volume of untreated water (in m ) that bypasses the plant as a result of the storm. (Note that
3
the plant still receives 5,000 m of domestic sewage per day.)
(e) Describe TWO ways that the volume of storm-water runoff can be reduced.
(f) Describe one environmental problem (other than pollution from runoff and from untreated sewage) that
results from having extensive paved areas.
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2014 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Plate-tectonic theory states that the Earth’s lithosphere is broken into very slowly moving pieces or plates.
Plate movements over vast stretches of time have led to the current orientation of our continents and oceans.
Individual events along plate boundaries, such as earthquakes and volcanic eruptions, pose periodic threats to
human activity and ecosystems. The “Ring of Fire” is a term that describes the location of increased seismic and
volcanic activity around the margins of the Pacific Ocean basin. On the map above, each dot represents a
volcano or an earthquake.
(a) Japan, Indonesia, and the Philippines are examples of volcanic island chains that have formed along
subduction zones between plates in the western Pacific.
(i) Describe what happens when two tectonic plates collide along a subduction zone.
(ii) Explain how subduction leads to volcanic activity.
(b) Although the landscape following a volcanic eruption may appear unable to support ecological communities,
over time the area can be transformed through succession.
(i) What is primary succession?
(ii) Explain how primary succession can lead to soil formation on a newly formed volcanic landscape.
(c) In addition to volcanic activity, highly destructive tsunamis are generated along Pacific Plate subduction
zones.
(i) Explain how a tsunami is generated along a subduction zone.
(ii) Describe one negative ecological impact that tsunamis have on coastal environments.
(d) Southern California experiences periodic devastating earthquakes along the San Andreas Fault, which is a
transform boundary located along the eastern edge of the Pacific Plate.
(i) Describe what happens to the tectonic plates along a transform boundary at the moment when an
earthquake occurs.
(ii) Describe what happens to the tectonic plates along a transform boundary during the time between
earthquakes.
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2014 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. Biogeochemical cycles describe the movement of certain elements (typically bound with other elements in
compounds) through Earth’s atmosphere, hydrosphere, biosphere, and lithosphere. These elements and their
compounds are necessary components of all life, and because they cycle, they can be used repeatedly by new
generations of organisms. Each biogeochemical cycle has different pathways with various reservoirs (sources
and sinks) where elements may reside for days or millions of years.
(a) The atmosphere is one important carbon reservoir.
(i) Describe
a biological process by which carbon is removed from the atmosphere and converted to
organic molecules.
(ii) Describe a biological process by which carbon is converted from organic molecules to a gas and
returned to the atmosphere.
(b) Oceans and terrestrial systems are also important carbon reservoirs.
(i) Explain
how atmospheric carbon is incorporated into two oceanic sinks.
(ii) Identify one terrestrial sink, other than fossil fuels, that stores carbon for thousands to millions of
years.
(c) The burning of fossil fuels has been shown to increase the concentration of carbon in the atmosphere.
Discuss TWO other human activities that increase the concentration of carbon in the atmosphere.
(d) Identify an environmental problem that results from elevated atmospheric carbon concentrations. Discuss one consequence of the problem you identified. (e) Phosphorus is another element important to all organisms.
(i) Describe
one major way in which the phosphorus cycle differs from the carbon cycle.
(ii) Identify one reason that phosphorus is necessary for organisms.
STOP END OF EXAM © 2014 The College Board. Visit the College Board on the Web: www.collegeboard.org.
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AP Environmental Science
2015 Free-Response Questions
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2015 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
ENVIRONMENTAL SCIENCE
SECTION II
Time— 90 minutes
4 Questions
Directions: Answer all four questions, which are weighted equally; the suggested time is about 22 minutes for
answering each question. Write all your answers on the pages following the questions in this book. Where
calculations are required, clearly show how you arrived at your answer. Where explanation or discussion is
required, support your answers with relevant information and/or specific examples.
1. Read the article below and answer the questions that follow.
(a) Describe how TWO human activities, other than those that result in anthropogenic climate change,
have resulted in a decrease in the amount of freshwater flowing into the Everglades ecosystem.
(b) In addition to water quantity problems, the Everglades is faced with a variety of water quality issues.
For example, phosphorus concentrations in the Everglades have increased since the 1960s.
(i) Describe how one specific human activity contributes to increased phosphorus levels in the
Everglades.
(ii) Explain one way in which an increase in phosphorus levels can adversely affect the Everglades
ecosystem.
(iii) Describe one step that could be taken to reduce phosphorus inputs from the activity you identified
in part (i).
(c) Climate change could have a variety of impacts on water quantity, water quality, and habitat. For EACH
of these three factors, identify and describe one specific example of an impact on the Everglades likely to
result from climate change.
(d) The article states that Governor Moss believes that the “preservation and enhancement of the Everglades,
key goals of the restoration program, are absolutely essential for the continued environmental and economic
health of the state.”
(i) Describe one way that restoring water quantity and water quality in the Everglades is expected to
improve the structure and function of the ecosystem.
(ii) Describe one way that restoring the Everglades is expected to provide economic benefits to Florida.
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2015 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
2. Approximately 30 million mobile devices were sold in 1998 in the United States. The number sold increased to
180 million devices in 2007.
(a) Calculate the percent increase of mobile device sales from 1998 to 2007.
(b) Each mobile device sold in 2007 contained an average of 0.03 gram of gold. Calculate the number of grams
of gold that were used in the production of the mobile devices sold in 2007.
(c) Assume that the average mass of each mobile device was 0.1 kilogram. The United States Environmental
Protection Agency estimates that about 10 percent of the mobile devices sold in 2007 were recycled.
Calculate the mass (in kilograms) of the mobile devices sold in 2007 that were not recycled.
(d) Discarded mobile devices become part of the electronic waste stream (e-waste). Mercury is often present in
e-waste. Identify one negative human health effect, other than death, associated with exposure to mercury.
(e) Improper disposal of e-waste has harmed human health and caused environmental damage in developing
countries.
(i) State TWO reasons why large quantities of e-waste from the United States are shipped to developing
countries rather than being recycled in the United States.
(ii) Retailers or manufacturers could take specific steps to dramatically reduce the amount of e-waste.
Describe a realistic change in current practices that would accomplish this.
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2015 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
3. Oil spills can be devastating in scope and damage. Since 1900, there have been many oil spills around the world
that have had significant ecological and economic impacts.
(a) Using the data in the graph above, determine the maximum volume of oil estimated to have been spilled
during the Deepwater Horizon (BP) incident.
(b) Describe TWO environmental problems that can result from oil spills in coastal areas.
(c) Identify one economic impact that results from oil spills in coastal areas.
(d) Chemical dispersants have been used in cleanup efforts following major oil spills.
(i) Discuss both one advantage and one disadvantage of the use of chemical dispersants for oil spill
cleanup.
(ii) Identify either one biological or one physical method (other than chemical dispersal) used for oil spill
cleanup in coastal waters or on beaches and describe how the method is used.
(e) Catastrophic spills make up less than 20 percent of the oil that pollutes marine waters. Identify one other
source of oil contamination and explain how the oil from this source enters marine waters.
(f) Petroleum has many uses as a raw material for consumer goods. Identify one substitute for petroleum in
a specific consumer product (other than fuel).
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2015 AP® ENVIRONMENTAL SCIENCE FREE-RESPONSE QUESTIONS
4. The term “urban sprawl” describes the expansion of cities into rural areas. This phenomenon has occurred
around the world and has had economic, health, and environmental consequences.
(a) Describe TWO causes of urban sprawl.
(b) Discuss TWO human health effects associated with urban sprawl.
(c) The graph below shows the relationship between population density and petroleum use in selected cities.
Describe the relationship between population density and petroleum use shown in the graph.
(d) Smart growth focuses on ways to encourage sustainable urban development. Describe TWO steps a
municipality could take to encourage smart growth in order to limit urban sprawl.
(e) Highway systems and urban sprawl often threaten wildlife populations. Describe TWO methods to reduce
harmful effects on wildlife populations from highways and urban sprawl.
(f) Urban sprawl often results in the loss of productive agricultural land near cities. Describe one practical way
to increase food production within urban areas.
STOP
END OF EXAM
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