FS-951
Ecosystem Services Edition • http://www.naturalinquirer.org

Produced by:

The Forest Service and the U.S. Geological Survey

Editors:

Babs McDonald, Forest Service

Jessica Nickelsen, Cradle of Forestry Interpretive Association

Rachel Small, Cradle of Forestry Interpretive Association

Michelle Andrews, University of Georgia

Graphic Designer:

Carly Morganwalp, U.S. Geological Survey

Forest Service scientists highlighted in the journal:

Dr. Ariel Lugo, International Institute of Tropical Forestry

Dr. Alice Chung-MacCoubrey, Rocky Mountain Research 

Station (formerly)

Dr. Diane DeSteven, Southern Research Station

U.S. Geological Survey scientists highlighted in the journal:

Dr. Robert Gleason, Northern Prairie Wildlife Research Center

Dr. Ned Euliss, Northern Prairie Wildlife Research Center

Mr. Brian Tangen, Northern Prairie Wildlife Research Center

Dr. Glenn Guntenspergen, Natural Resources Research Institute

Other scientists highlighted in the journal:

Dr. Tom Crist, Miami University

Dr. Bob Parmenter, Valles Caldera Trust, New Mexico

Dr. Heather Bateman, University of New Mexico

Dr. Chrissa Stroh, National Oceanic and Atmospheric 

Administration

Mr. Murray Laubhan, Kansas Department of Wildlife & Parks

Dr. Mary Harner, University of New Mexico

Forest Service

Tom Tidwell, Chief

Ann Bartuska, Deputy Chief, Research and Development

Jim Hubbard, Deputy Chief, State and Private Forestry

John Sebelius, Staff Director, Science Quality Services

Safiya Samman, Staff Director, Conservation Education

Rob Doudrick, Staff Director, Resource Use Science

Greg Arthaud, Research Social Scientist, Resource Use Science

U.S. Geological Survey

Marcia McNutt, Director 

Suzette Kimball, Deputy Director 

D. Bryant Cramer, Associate Director for Geography 

Ione L. Taylor, Chief Scientist for Geography 

Susan D. Haseltine, Associate Director for Biology 

K. Bruce Jones, Chief Scientist for Biology 

Carl Shapiro, Chief, Office of Science, Decisions, and 

Resource Management

With thanks to:

Cradle of Forestry Interpretive Association

Alex Comfort, Executive Director

Bill Alexander, Chairman

Rita Brown, Forest Service Conservation Education Coordinator

Dianna Hogan, U.S. Geological Survey 

Project Learning Tree

http://www.plt.org

Natural Inquirer Ecosystem Services Edition • Volume 12, Number 1, Spring 2010
The Natural Inquirer • Volume 12 Number 1

“The pictures help explain things, 

so it is not just words.”

“I like this glossary. It makes the 

words more clear.”

Editorial Review Board

Student Editorial Review Board Comments

“I think you should put more pictures in to 

make the article more interesting.”

“This is pretty cool because it’s about 

someone going out and having fun with 

earth and water stuff.”

Janet Johns’ 7th grade classes, Cass Middle School, Cartersville, Georgia

3
4

Ecosystem Services Edition • http://www.naturalinquirer.org 

3 Editorial Review Board

5 About the Natural Inquirer

5 Who Are Scientists?

6 Welcome to the Ecosystem Services Edition of the Natural Inquirer!

Contents

10	 Toad-ally Awesome! Investigating the Relationship Between Flooding and Toad

Reproduction Along the Rio Grande

20	 What Goes Around Comes Around: How Long-Term Weather Patterns Affect

Plants in Carolina Bay Wetlands

32	 Think Outside the Box: Predicting the Spread of Invasive Species

40	 Fill Those Potholes! Identifying Ecosystem Services of Small Wetlands on the

American Prairie

52 Crossword Puzzle and Word Search

54 Note to Educators

55 Lesson Plan

64 National Science Education Standards for the 

Ecosystem Services Edition of the Natural Inquirer

Inside 

back cover What is the Forest Service?

Inside 

back cover What is the U.S. Geological Survey?

Back cover Editorial Review Board

Back cover Web Sites

Features
5

The Natural Inquirer • Volume 12 Number 1

About the Natural Inquirer

Scientists report their research in journals, 

which are special booklets that enable 

scientists to share information with one another. 

This journal, the Natural Inquirer, was created 

so that scientists can share their research with 

you and with other middle school students. 

Each article tells you about scientific research 

conducted by scientists in the U.S. Department 

of Agriculture (USDA) Forest Service. If you 

want to know more about the Forest Service, 

you can read about it on the back cover of 

this journal, or you can visit the Natural Inquirer

Web site at http://www.naturalinquirer.org.

All of the research in the Natural Inquirer is 

concerned with nature, such as trees, forests, 

animals, insects, outdoor activities, and 

Scientists are people who collect and evaluate information about a wide range of topics. 

Some scientists study the natural environment. To be a successful environmental scientist, you must:

Be curious – You must be interested in learning.

Be enthusiastic – You must be interested in an environmental topic.

Be careful – You must be accurate in everything that you do. 

Be open minded – You must be willing to listen to new ideas.

Question everything – You must think about what you read 

and observe.

Who Are Scientists?

water. First, you will “meet the scientist” who 

conducted the research. Then you will read 

something special about science and about the 

natural environment. You will also read about 

a specific research project. This is written 

in the format that scientists use when they 

publish their research in journals. Then,YOU 

will become the scientist when you conduct the 

FACTivity associated with each article. Don’t 

forget to look at the glossary and the special 

sections highlighted in each article. These 

sections give you extra information. 

At the end of each section of the article, you 

will find a few questions to help you think about 

what you have read. They should help you to 

think more about the research. Your teacher 

may use these questions in a class discussion.
6

Ecosystem Services Edition • http://www.naturalinquirer.org 

Welcome to the Ecosystem Services 

Edition of the Natural Inquirer!

Have you ever heard 

the term “ecosystem 

services?” Can you 

imagine what ecosystem 

services might be? 

Ecosystem services are provided by healthy 

natural areas just because they are healthy 

natural areas. Ecosystem services are valued 

by people, even if people do not always 

think about where these services come from. 

Examples include clean air, clean water, 

beautiful landscapes, healthy soil, places for 

wildlife to live, minerals, and even places to do 

outdoor activities. Even pollination is considered 

an ecosystem service because pollination is 

important to the production of food. 

Ecosystem services are important because 

they provide goods and services that are 

vital to human health and quality of life. 

Ecosystem services are life-support systems for 

plants, animals, and humans worldwide. Some 

ecosystem services are called “public goods” 

because they are available to everyone 

(such as clean air). The process of waste 

decomposition and carbon storage are more 

examples of ecosystem services. 

Scientists have studied ecosystems for a 

long time. The concept of ecosystem services, 

however, is relatively new. The identification 

of ecosystem services allows scientists to let 

people know that ecosystems are important 

to everyone. Some people value ecosystem 

services for the wildlife they support, while 

others may have greater appreciation for 

services such as food or energy production. 

Everyone benefits from ecosystem services, and 

the prosperity of humans, past, present, and 

future, is dependent upon healthy ecosystems.

Although it is difficult to put a price on clean 

air, for example, scientists have begun to look 

at the monetary value of ecosystem services. 

When the monetary value of ecosystem 

services is not known, the ecosystem may be 

destroyed in favor of something on which 

we can place a price. For example, when a 

forest is destroyed so a building can be built, 

the forest no longer provides the ecosystem 

service of holding carbon, providing homes for 

songbirds, or cleaning the air. By identifying 

and placing a value on ecosystem services, 

people are able to make better decisions. 

In this edition of the Natural Inquirer, you will 

learn new and different things about ecosystem 

services. Then you can look around you and 

identify the services being provided to you and 

your community by the natural world!
7

The Natural Inquirer • Volume 12 Number 1

What are Ecosystem Services?

Resurrection Bay, Alaska: Bare rock 

provides a place for animals to 

bask in the sun. Marsh west of Jekyll Island, Georgia: 

Wetlands provide habitat for many animals 

and filter pollutants from the water.

Bentonville, Arkansas: Some animals, 

including some insects, birds, and bats, 

are pollinators. Pollination is essential for 

the reproduction of fruits, vegetables, 

and flowers.

Near Salzburg, Austria: Forests 

provide many ecosystem 

services. They provide homes 

for animals and plants, 

resources for people, help to 

reduce the impact of global 

climate change, clean the air, 

and provide clean water.

Holgate Glacier, Aialik Bay, Alaska: Glaciers 

provide a continual source of fresh water. Scientists 

study glaciers for clues about Earth’s natural history.

Berkeley Springs, West Virginia: Trees act 

as umbrellas by catching rain drops. This 

decreases the amount or slows the rate of 

water reaching the ground, and helps to 

reduce soil erosion and flooding.

Ben Eighe National Nature Reserve, Scotland: 

Natural resources provide areas for people to 

enjoy the outdoors.

Hard Labor Creek State Park, Georgia: 

Decaying leaf litter helps to build the 

soil and provides a home for animals. 

Animals, such as snakes, are part of a 

healthy ecosystem.
8

Ecosystem Services Edition • http://www.naturalinquirer.org 

What is Geography?

Geography is the study of Earth, its land, 

and its inhabitants. A geographer studies 

places where life is found and the way living 

beings interact with their Earth home. In this 

Natural Inquirer, you will learn about how 

geographers study ecosystems as special places 

and how people, other animals, and plants 

interact with and gain value from ecosystems.

Scientists with the United States Geological 

Survey, or USGS, often use satellites to study 

geographic questions on Earth. Satellites 

continually orbit Earth, collecting information 

about our planet (figure 1). For example, 

USGS scientists use information from satellites 

to track the dates that leaves unfold in spring 

and fall off of trees in autumn. This helps them 

to identify how changes in an area’s climate 

affect the growth of trees. Information from 

satellites has also been used to create a map 

that shows the types of ecosystems found in 

the United States. This map will help scientists 

better understand the types and values of the 

ecosystem services provided. 

USGS geographers 

also do research within 

ecosystems themselves. 

One place these 

geographers are studying 

is the Everglades. This is 

a large wetland area 

running through the middle 

of south Florida. Wetlands 

are areas of land that 

are sometimes covered 

by water, and often they 

are beside areas of 

water. Wetlands provide 

many ecosystem services 

to people including clean 

water, clean air, and 

natural places for many 

animals and plants to live. 

Glossary

inhabitant (in hab uh tent): 

One who occupies a particular area. 

Figure 1. Landsat satellite orbiting Earth. Photo courtesy of NASA
9

The Natural Inquirer • Volume 12 Number 1

Because the Everglades 

provides a variety of ecosystem 

services, it is important to make 

good decisions about how it is 

managed. USGS geographers 

have created a computer 

program that uses maps to help 

get the most out of the ecosystem 

services provided by the 

Everglades (figures 2, 3, and 4).

Figure 2. Dr. Bill Labiosa helps people think 

about the different effects that decisions have 

on alligators in the Everglades. Unless you are 

a scientist studying alligators, remember not 

to get close to an alligator!

Figure 3. Dr. Dianna Hogan studies the way people use land in the 

Everglades, and how that affects the ecosystem services they receive. 

She especially likes to study plants and animals. This Double-crested 

Cormorant (next to Dr. Hogan) catches fish in the Everglades using its 

hooked bill.

Figure 4. Mr. David Strong provides the computer 

and GIS (Geographic Information System) computer 

program that allows the scientists to answer their 

questions. Here, Mr. Strong works on his computer 

from the trunk of his car.

As you read this Natural Inquirer, think about 

geography and how it helps people to better 

understand and protect our planet. As you read each 

article, identify which of the following geography 

questions the article is describing:

• How do maps and images help us better understand the environment?

• How do life forms behave in their own environment?

• How do life forms behave differently in different environments?

• How do life forms move from one place to another?

• How do life forms change the environment?

• How do people change the environment and how does that 

affect other life forms?

• How are places different?

• How are different places similar?
10

Ecosystem Services Edition • http://www.naturalinquirer.org 

Toad-ally 

Awesome!

Investigating the Relationship Between 

Flooding, Summer Rains, and 

Toad Reproduction Along the Rio Grande
11

The Natural Inquirer • Volume 12 Number 1

Meet the Scientists

Dr. Heather Bateman: My favorite science 

experience has always been working with 

wildlife. I enjoyed placing leg bands on longeared owls in the United States Great Basin. I also 

enjoyed tagging lava lizards on the Galapagos 

(ga lop uh gos) Islands. One day, I spent over 

12 hours measuring and weighing hundreds of 

toadlets, or small toads. They had been laid as 

eggs in pools of water in a riparian (ri pair e an) 

forest after a spring flood. A riparian forest is a 

forest located next to a body of water. Later, the 

frogs underwent metamorphosis, developing from tadpoles to toadlets. They fell into traps that 

we used to count and release them. The toadlets were about the size of my thumbnail. 

Dr. Mary Harner: My favorite 

science experiences are conducting 

field research along rivers and in 

the tropics. Recently, I have had the 

fortune to study the ecology of bats 

on the island of Trinidad, located off 

the coast of Venezuela, as well as 

the ecology of plants along rivers in 

North America and in Europe. I enjoy 

being outdoors, studying organisms 

in their natural environments, and 

working with groups of scientists who 

have a broad knowledge of nature.
12

Ecosystem Services Edition • http://www.naturalinquirer.org 

Dr. Alice Chung-MacCourbrey: My 

favorite science experience was a research 

project that allowed me to combine two of 

my biggest interests, dogs and bats. Dogs 

have a superb sense of smell that can be 

used in wildlife research. My dog used 

to accompany me in the field while I was 

radiotracking bats to find their tree roosts, 

and it was clear that she could smell the bats. 

In summer 2006, I tested my hypothesis that 

dogs could be used to locate bat roosts and 

conducted field tests using professionally 

trained scent detection dogs to locate bat 

tree roosts (by finding guano piles which are 

piles of bat poop). The dogs sniff out the 

guano. When they find the guano they sit 

by the tree and are rewarded with a short 

game of fetch.

metamorphosis (met uh môr fuh sis): 

The process of changing in form, for some 

animals, from an immature stage to 

an adult stage.

migratory (mi gruh tôr e): 

Having a characteristic of moving from one 

place to another on a periodic basis.

regulation (reg u la shun): 

Bringing under control of law or 

some authority.

flood plain (fluhd plan): 

Flat land area next to a stream or river.

headwaters (hed wa türs ): 

The upper streams that contribute water to 

another source of water such as a river.

semi-arid (sem i air id ): 

An area that receives very little rainfall.

a as in ape

ä as in car

e as in me

i as in ice

o as in go

ô as in for

u as in use

ü as in fur

oo as in tool

ng as in sing

Accented syllables 

are in bold.

Glossary Pronunciation 

Guide
13

The Natural Inquirer • Volume 12 Number 1

Floods – Friend or Foe?

When you hear about flooding in the 

news, it seems as if flooding is not a good 

thing. Floods, however, can be beneficial 

to many types of animals and plants. 

Rivers carry sediment and nutrients in 

their waters. When flooding occurs, the 

sediment and nutrients are deposited on 

the land next to the river. The flooding 

helps to enrich the soil. The nutrient-rich 

soil is a good thing for the plants that live 

there. If plants benefit from flooding, the 

animals that live there will benefit also. 

In some places, flooding is a signal for 

migratory fish to migrate. Flooding 

provides a way for separate bodies 

of water to connect for a while, 

which provides an opportunity for 

native animals and plants to move 

to new environments.

Flooding is also a natural way of 

helping some plant and animal species 

reproduce and survive. For example, 

frogs and toads are tadpoles before 

they develop into adult frogs and toads. 

To develop into adults, tadpoles require 

water. In fact, frogs and toads must 

also have water to lay their eggs. In this 

study, the scientists were interested in 

how flooding might provide a place for 

toads to reproduce in a dry region of 

the Southwestern United States. 

As you can see, flooding can be 

beneficial to plants and animals 

that live along a river’s banks.

Taking measurements is a common 

practice in everyday life. Most scientific 

experiments involve units of measurement. 

Units of measurement are things like inches 

or centimeters, miles or kilometers per hour, 

ounces or grams, or frequency. A scientist may 

want to know, for example, how many times a 

Screech owl visits a particular Red Oak tree 

during the summer. In that case, the unit of 

measurement is frequency. Think of three 

things you have measured today. As 

you read the “Introduction” section 

of the article, make a guess as to 

what the scientist will measure in 

the research. Identify what unit of 

measurement was used.

Thinking About 

 the Environment

Think about what it takes for you to survive 

everyday. Aside from food and water, humans 

need clothing and shelter. If adults are raising 

a family, they must provide for their families 

as well. Animals must also have certain 

things to survive. They need a place to live, 

things to eat, and a place to reproduce. The 

environment in which a species lives is called 

its habitat. In the study you are about to 

read, scientists wanted to learn about the best 

habitat for toads to reproduce. While reading 

the article, identify how humans impact the 

habitat of toads. Remember that humans 

have both positive and negative effects on an 

animal’s habitat.

Thinking About 

 Science
14

Ecosystem Services Edition • http://www.naturalinquirer.org 

Most rivers in the United States are 

now regulated. A regulated river is one 

whose flow is controlled by dams. For 

people, the regulation of rivers provides 

protection from flooding, as well as reliable 

sources of water for drinking and cooking, farming, 

and industry. The regulation of rivers, however, 

alters the relationship between rivers 

and their floodplains. When a 

floodplain floods, the water provides a 

needed habitat for some animal and 

plant species. Floodplains may also 

flood after rains occur downstream 

from the dam. When dams are built in 

river systems, however, wet floodplain 

habitats are less available.

The scientists in this study were 

interested in studying how toads 

reproduce in the floodplains along 

the Rio Grande. The Rio Grande is a 

river that flows from its headwaters

in southern Colorado for 1,865 

miles to the Gulf of Mexico near 

Brownsville, Texas (figures 1 and 2). 

The Rio Grande is regulated by four dams that 

control the river’s flow (figure 3). The scientists 

studied a section of the Rio Grande in a semiarid area in New Mexico that could occasionally 

flood. The question the scientists wanted to 

answer was this: How does flooding affect 

the reproduction of toads in the forests, or the 

bosque, along the Rio Grande?

Introduction

Figure 1. The Rio 

Grande from southern 

Colorado to the Gulf of 

Mexico. The Rio Grande 

is the border between 

the State of Texas and 

country of Mexico.

Figure 2. The Rio Grande. The United States is on the right and the 

country of Mexico is on the left. In some areas, the Rio Grande still 

occasionally floods. Notice the strip of green vegetation along the river 

banks. This is the Rio Grande’s forested floodplain. Along the Rio Grande, 

the forested floodplain is called the bosque (bosk or bos-key).

Figure 3. One of the dams on the Rio 

Grande. The lake created by the dam is on 

the right. The Rio Grande is on the left.
15

The Natural Inquirer • Volume 12 Number 1

Method

The scientists collected data from June 

through September 2000 to 2006. They 

monitored 12 sites in the bosque along 140 km 

of the Rio Grande in New Mexico (see figure

1). The scientists used pitfall traps (figure 4) 

and drift fences (figure 5) to capture toads at 

each site. They counted and weighed the toads 

and then released them. 

The scientists also measured other things at 

each of the 12 sites. They recorded the amount 

of rainfall over the 7 years. They measured the 

amount of water flow in the Rio Grande. They 

also measured the level of the groundwater in 

the bosque. 

Figure 4. Pitfall trap

Figure 5. Drift Fence

Reflection Section • What was the question the scientists 

wanted to answer?

• How do you think flooding affects the 

reproduction of toads?

Reflection Section • Why did the scientists also measure the 

amount of rainfall and the amount of 

water flow at each of the sites?

• Why do you think the scientists 

conducted their experiment from June 

through September of each year?

Number Crunches

How many miles is 140 km? (km is an 

abbreviation for kilometers) To find out Multiply 140 km by .621.
16

Ecosystem Services Edition • http://www.naturalinquirer.org 

The scientists found that rainfall varied 

over the 7 years. In some years there was 

little rainfall, while in others there was a lot 

of rainfall. For most of the years, the scientists 

did not capture many toads. In 2005, however, 

two of the sites flooded. At those sites, the 

scientists captured many more toads (figure

6). Most of the toads captured in 2005 were 

small (compare figures 7 and 8). This told the 

scientists that there were many young toads at 

the two flooded sites.

Number of Toad Captures

Toad Size

2000-2004

2005

2006

■

■

■

600

500

400

300

200

100

0 Small Medium Large

Findings

Reflection Section • Look at figure 6. Do you think flooding 

affected the reproduction of toads? 

Why or why not?

• What other living things do you think 

might be affected by flooding? Why? Figure 7. Small Woodhouse’s toad

Figure 8. Adult Woodhouse’s toad

Figure 6. The average number of toads captured each 

month at all sites over 7 years.
17

The Natural Inquirer • Volume 12 Number 1

The scientists concluded that the capture 

of many small toads in the flooded areas 

meant that adult frogs had used the flooded 

areas for breeding. Since the Rio Grande is a 

regulated river, floods are no longer common. 

The scientists believe that purposely flooding 

the bosque at certain times would provide 

areas for toads to breed. These small floods 

could be safely managed to protect both 

people and the population of toads that live in 

the bosque.

1. Flat land area next to a stream or river.

2. The upper streams that contribute water to 

another source of water such as a river.

3. The process of changing in form, for some 

animals, from an immature stage to an 

adult stage.

4. Having a characteristic of moving from one 

place to another on a periodic basis.

5. Bringing under control of law or 

some authority.

6. An area that receives very 

little rainfall.

This article was adapted from Bateman, H.L.; Harner, M. J.; and 

Chung-MacCoubrey, A. (2008). Abundance and reproduction of 

toads (Bufo) along a regulated river in the southwestern United 

States: Importance of flooding in riparian ecosystems. Journal of 

Arid Environments. 72: 1,613-1,619. http://hbateman.faculty.asu.

edu/Publications.

Discussion Toad-ally Awesome 

Word Search

Reflection Section • Do you think it would be a good 

idea to purposely flood the bosque 

periodically? Why or why not?

• Would people benefit from flooding 

that would enable the toads to 

reproduce? Why or why not?

U R D L

O Y H G M Q Q J

H G H E A D W A T E R S Q P

K F L O X W C F C Q T J D R C

Z U J P L N R E G U L A T I O N

H Y R Y R O T A R G I M F R I I

O X Q C T P H G I K R O E A L

M O G S J U Z V W K A R L - N

G U I D Y L N F A P M I

Z J A B E T Y F D H G M V

G R D G P D G V O J O L E D C

E D B E C W M O O G S D S O Z

U I J B T D L M O I F A Q D

H Q P Z F T S O R P

P R J F A Y
18

Ecosystem Services Edition • http://www.naturalinquirer.org 

FACTivity The method you will use to answer these 

questions is:

Following the reading of the article: Make 

sure that everyone in your class has read and 

understands the “Toad-ally Awesome” article. 

In a rapid-fire exercise with the entire class, 

make a list of as many ecosystem services (or 

benefits) provided by the bosque as you can. 

Try to use your imagination to come up with 

benefits that may not have been discussed in 

the article. Put this list on the wall where it can 

be used during the next class period.

Next class period: Following the same 

procedure used to read “Toad-ally

Awesome,” read “Swimming Upstream Without 

a Ladder.” Organize into groups of 3 to 4 

students. Each group of students will compare 

and contrast the two articles.

Use the list of benefits identified earlier. 

Record similarities and differences using the 

chart on the next page.

Each group should share their findings 

with the class. Hold a discussion about the 

ecosystem services or benefits provided 

by waterways. Brainstorm other ecosystem 

services provided by waterways. Students 

should put their names on their charts and turn 

them in to the teacher. The teacher can use 

these charts as an assessment tool. 

Extension: Research waterways in your area 

and identify how those waterways benefit the 

plants and animals that live near them.

Teachers may use the lesson plan at the back 

of this journal to guide student reading of 

the article.

Time Needed: Two class periods.

Materials Needed:

• “Toad-ally Awesome” article

• “Swimming Upstream Without a Ladder” 

article (You may download and print this 

article or order it from the Natural Inquirer

Web site http://www.naturalinquirer.

org/Dams-and-Pipes-and-River-ShrimpMovementsa-11.html)

• Paper

• Pencils

You learned in this article that flooding can 

provide a service to the toads living along the 

Rio Grande in New Mexico. When flooding 

occurs in the spring, wet areas are created that 

provide places for toads to reproduce. In this 

FACTivity, you will answer these two questions:

1.	 What are the similarities of and

differences between flooding in the

bosque and the flow of mountain

streams in Puerto Rico?

2.	 How do the ecosystem services provided

by these two waterways compare?
Describe

(One sentence for 

each waterway)

Similarities Differences

The Waterway

The Land

The Animal Being 

Studied

The Climate

The Dams

Benefits Provided by 

the Waterway

19

The Natural Inquirer • Volume 12 Number 1

If you are a Project Learning Tree-trained educator, you may use PLT Activity #94, “By the Rivers of Babylon,” 

PLT Activity #9, “Planet Diversity,” and PLT Activity #29, “Rain Reasons” as additional resources. 

Additional	Web	Resources:

USGS’s Woodhouse’s Toad Page

http://www.npwrc.usgs.gov/resource/herps/amphibid/species/bwood.htm

National Park Service’s Rio Grande Web Page

http://www.nps.gov/rigr/
20

Ecosystem Services Edition • http://www.naturalinquirer.org 

How Long-Term Weather Patterns 

Affect Plants in Carolina Bay Wetlands

What Goes Around Comes Around:
21

The Natural Inquirer • Volume 12 Number 1

Meet the Scientists

Ms. Chrissa Stroh, Coastal Ecologist: I 

have wonderful science experiences every 

day! Watching the sun rise, seeing birds fly 

overhead, or observing the neat shapes of 

flowers and leaves on plants outside. One of 

my favorite science experiences was visiting 

the Volcano Arenal (är ah nul), an active 

volcano in Costa Rica. I was there as the sun 

was going down, and was able to see and 

hear red-hot lava rocks tumbling down the 

sides of the volcano.

Dr. Diane De

Steven, Wetland 

Plant Ecologist: My 

favorite science 

experience is 

working in the field 

and observing 

the plants and 

animals of different 

habitats. I can get a break from city noises, hear the quiet sounds of 

nature, and appreciate the great diversity of life. My research has 

allowed me to visit tropical rainforests, prairies, mountain forests, 

deserts, and (of course) many types of wetlands.

Dr. Glenn Guntenspergen, Landscape Ecologist: As a 

young boy, I owned and read every Tom Swift, Jr., book 

ever written. Those books inspired me to become a 

scientist, and throughout my adult life I have 

had a steady stream of inspiring science 

experiences—all of which I treasure.
22

Ecosystem Services Edition • http://www.naturalinquirer.org 

classification (cla suh fuh ka shun): A 

method used by scientists to group or 

categorize species of organisms.

vegetation (ve juh ta shun): Plant life.

wetland (wet lend): Areas of land with a 

lot of soil moisture.

aquatic plants (uh kwat ik plants): Plants 

growing or living in or upon water.

marsh plants (märsh plants): Plants growing 

in dry areas outside wetlands.

woody plants (wood e plants): Plants growing 

in dry areas outside wetlands in the ecosystem.

freshwater (fresh wä tür): Water source 

that has low amounts of salt concentration.

ecosystem services (e ko sis tem sür vis es): 

Environmental health benefits provided by a 

community of plant and animal species.

drought (drowt): A period of dry weather 

with little or no rain.

ecosystem (e ko sis tem): Community 

of plant and animal species interacting 

with one another and with the nonliving 

environment.

model (ma del): A simplified example of a 

system in science.

cyclical (sik kli kül): Occurring in a pattern 

that typically happens again and again.

indicator (in di ka tôr): Something that 

symbolizes something else.

sample (sam pul): A small part of a group.

annual (an u ul): Occurring every year.

concentric (kän sen trik): Having a common 

center.

population (päp yoo la shun): The whole 

number of individuals of the same type 

occupying an area.

Glossary Thinking About 

Science

When scientists want 

to solve a problem, 

they collect information 

to understand the 

problem. To understand 

the information, scientists 

sometimes use a technique 

called classification. Classification helps 

scientists group and categorize many things 

into simpler groups. This technique can create 

groups that can be compared to each other. 

For example, if someone gave you a bag of 

a as in ape

ä as in car

e as in me

i as in ice

o as in go

ô as in for

u as in use

ü as in fur

oo as in tool

ng as in sing

Accented syllables 

are in bold.

Pronunciation 

Guide
23

The Natural Inquirer • Volume 12 Number 1

coins, would it be easier to count 

the coins one by one? Or would 

it be easier to put the pennies 

with each other, the quarters 

with each other, and so on? It is 

much easier to count the money 

by classifying it rather than 

counting the coins one by one.

In this study, scientists classified 

vegetation in and around 

wetlands. The scientists classified 

the plants into three groups: 

aquatic plants, marsh plants, 

and woody plants. Aquatic plants 

include plants like water lilies that are found 

growing in water. Marsh plants, like grasses, 

can grow in shallow areas between deeper 

water and dry areas. Woody plants, like trees 

and shrubs, are plants that live in dry areas 

outside wetlands. This type of classification 

helps scientists to simplify and compare the 

data they collected in the study area.

Thinking 

About 

the 

Environment

Why should we 

care about freshwater wetlands? Freshwater 

wetlands play an important role in an 

ecosystem by providing ecosystem services

throughout the world (figure 1). Freshwater 

wetlands help clean the water by removing 

pollution. They act like a storage unit when 

Figure 1. Wetlands of the United States of America. 

Image created by Robert H. Yuhas of the United States 

Geological Survey. 

floods occur. Water is held in the wetland 

rather than flooding people’s homes and cities. 

These wetlands are also homes and breeding 

areas for many different types of wildlife 

– For example, ducks, frogs, salamanders, 

beavers, fish, alligators, and many more. 

Freshwater wetlands depend on rainfall to 

stay wet. When a drought occurs, the water 

levels drop. Sometimes the wetland dries up 

all the way. If there is not enough water in the 

wetland, then this can change how the wetland 

does its job in the ecosystem. The scientists 

in this study were interested in how different 

amounts of rainfall affect wetlands.
24

Ecosystem Services Edition • http://www.naturalinquirer.org 

Shallow land depressions can be found 

within some forests of the United States. These 

depressions are filled by rainfall, particularly 

in the spring when the rains are most frequent. 

In certain areas of the Southeastern United 

States, these wet depressions are called 

Carolina bays (figure 2). Throughout the 

summer months, Carolina bays dry up as rain 

becomes less frequent and the temperature 

increases. The period from when the Carolina 

bays are filled by rain to the time they dry 

Introduction

What does hydro mean? “Hydro” can 

be a part of many different words, but 

it always relates to water (figure 4). 

Knowing what hydro means can help you 

understand what the whole word means. 

For example, hydrology means the study 

of water. Dehydrate means loss of water 

for normal body function. What do you 

think hydropower means? 

up is called a hydroperiod (hi dro per e 

ud). When these bays have water, aquatic 

plants grow in the water, and marsh plants 

or woody plants grow along the wet edge of 

the wetlands (figure 3). A Carolina bay is a 

freshwater wetland.

Figure 2. A Carolina bay. 

Figure 3. A Carolina bay filled with water and aquatic plants. 

Figure 4. The energy created by damming waterways is 

called hydropower.
25

The Natural Inquirer • Volume 12 Number 1

You may recall that freshwater wetlands 

provide a lot of benefits. (See “Thinking 

About the Environment.”) The scientists in this 

study were interested in whether prolonged 

periods of drought may enable trees and 

other woody plants to grow into the wetlands 

during the long dry periods. If that happened, 

the wetlands could change into a forested 

wetland (swamp.) This is called the directional 

model. It is called directional because the 

bays would change in only one direction. Think 

about how people develop and change. Think 

about how people change from being a baby 

to child to teenager to adult. People do not go 

from baby to teenager to baby to teenager 

to adult. Human development represents a 

directional model.

Other scientists proposed 

that Carolina bays could 

survive long periods of 

drought. This is called the 

cyclical model, because in 

this model the bays always 

return to their aquatic 

ecosystem. 

Those scientists, however, 

had only studied Carolina 

bays for short periods of 

time. The scientists in this study 

wanted to study Carolina 

bays over a longer period 

of time. The question they 

wanted to answer in this study was: Over 

a long period of time following periods of 

drought, do Carolina bays become more 

forested or do they always return to their 

aquatic ecosystem?

Figure 5. The study area was located in the 

Savannah River Site in South Carolina along its 

border with Georgia in the Southeastern 

United States.

Reflection Section • What would happen to the Carolina 

bays if the directional model were 

correct? What would happen if the 

cyclical model were correct? 

• What question did the scientsts ask? 

Method

The research was conducted in an area 

in the Savannah River Site in South Carolina 

along its border with Georgia in the 

Southeastern United States (figure 5). The 

scientists identified seven Carolina bays in this 

area. In the spring, each of these bays was 

filled with water. The smallest bay was 4.5 

hectares and the largest was 12 hectares. 
26

Ecosystem Services Edition • http://www.naturalinquirer.org 

Number Crunches

How many acres were the smallest and 

largest bays? Hint: Multiply the number of hectares by 2.47 to find out.

Number Crunches

How many yards apart were the cables 

marked? Hint: Multiply 10 meters by 

1.09 to find out. How many feet apart were the cables marked?

To answer their question, the scientists 

decided to use the type of vegetation and the 

depth of the water as indicators. To measure 

water depth, the scientists used a water gauge 

(figure 6). The water gauge also helped the 

scientists to measure hydroperiod. 

The bays were too large to identify 

all of the plants growing in them. 

To decide where in each bay the 

scientists would identify plants, they 

developed a special system to sample

the vegetation. The scientists placed 

a post in the middle of each Carolina 

bay. They connected eight cables to the 

center post. Each cable was pulled out 

to the edge of the bay and connected 

to a post at the water’s edge. The 

cables were evenly spaced. Each cable 

was marked every 10 meters (figure 7).

Scientists recorded the types of plants 

growing under the eight cables in the places 

that had been marked. (See Ms. Stroh’s photo, 

page 21.) They then classified the vegetation 

into three types, depending on how much 

water the plant needed to survive. The types 

were aquatic plants, marsh plants, and woody 

Figure 6. Water gauge in a forested swamp. plants (figure 8).

Figure 7. Diagram of the sampling method. 

Figure 8. Examples of the three types of vegetation 

identified by the scientists. 

Low Water Level

High Water Level

Woody Plants

Marsh Plants

Aquatic Plants
27

The Natural Inquirer • Volume 12 Number 1

Number Crunches

Although the bays were not a perfect circle, you could draw an imaginary circle 

with the post as the center (see figure 7). You know that a circle has 360 degrees. If 

the eight cables were evenly spaced, how many degrees apart was each cable?

The scientists also collected information 

about annual rainfall (figure 9). This way, they 

could identify times of drought. The scientists 

collected information about water depth and 

vegetation in the summers from 1983 to 2003. 

They also recorded the hydroperiod of each 

bay for every year. 

Figure 9. Average annual rainfall at the Savannah River 

Site from 1983 to 2003. 

Reflection Section • How do you think changes in rainfall 

affected the aquatic plants, marsh 

plants, and woody plants around 

the wetland?

• An ecosystem is a very fragile system. 

When something disrupts the balance, 

the ecosystem may take years to 

recover. Do you think rainfall only 

affects vegetation in the current year 

or can rainfall affect how vegetation 

grows the next year? Explain. 

The scientists then compared the amount 

of rainfall, water depth, and hydroperiod 

with the type of vegetation growing in each 

Carolina bay. They did this over a 15-

year period, paying close attention to what 

happened to the vegetation after a period 

of drought.

Rainfall (mm)

1800

1600

1400

1200

1000

800

600

400

200

0 1

9

8

3

1

9

9

0

1

9

9

7

1

9

8

4

1

9

9

1

1

9

9

8

1

9

8

5

1

9

9

2

1

9

9

9

1

9

8

6

1

9

9

3

2

0

0

0

1

9

8

7

1

9

9

4

2

0

0

1

1

9

8

8

1

9

9

5

2

0

0

2

1

9

8

9

1

9

9

6

2

0

0

3

Average Rainfall from 1983-2003
28

Ecosystem Services Edition • http://www.naturalinquirer.org 

The scientists discovered that when the 

bays were the driest, the fewest amounts of 

aquatic plants were found because of the 

low water levels in each bay. Instead, woody 

and marsh plants could grow and expand 

into the wetland. When the rains returned, the 

vegetation started to change again. During 

this recovery period, the deeper water caused 

woody and marsh plants to decrease. Once 

the bays contained a lot of water, the aquatic 

plants appeared again (figure 11). 

Figure 10. The graph shows the average maximum water 

depth at the water gauge of seven Carolina bays from 

1989 to 2003. Compare this graph with figure 9.

The scientists found that over a long period 

of time, the bays’ vegetation patterns show 

a cyclical model rather than a directional 

model. The scientists also found that vegetation 

patterns were influenced by current-year 

rainfall and last year’s rainfall. It can take up 

to a year for the water in a bay to recover 

from a drought period (figure 10)! 

Findings Rainfall (mm)

Year

1.8

1.6

1.4

1.2

1

0.8

0.6

0.4

0.2

0

1

9

8

9

1

9

9

0

1

9

9

7

1

9

9

1

1

9

9

8

1

9

9

2

1

9

9

9

1

9

9

3

2

0

0

0

1

9

9

4

2

0

0

1

1

9

9

5

2

0

0

2

1

9

9

6

2

0

0

3

Average Water Depth at Water Gauge
29

The Natural Inquirer • Volume 12 Number 1

Reflection Section • How is the pattern of a person’s 

development similar to or different from 

a Carolina bay? 

• How do you think aquatic plants return to 

the bay after a drought period? 

Reflection 

Section • How could climate 

change affect wetlands? 

• What would happen if 

all the Carolina bays 

dried up completely? 

How do you think 

this would affect the 

surrounding ecosystem? 

Think about plants, 

animals, and humans.

The scientists gained a better understanding 

of Carolina bays’ vegetation patterns. 

Carolina bays’ vegetation patterns show a 

cyclical model over a long period of time, 

depending on the amount of rain. These 

findings will help predict how other freshwater 

Discussion

This article was adapted from Stroh, C.L.; De 

Steven, D.; and Guntenspergen, G.R. (2008). 

Effect of climate fluctuations on long-term 

vegetation dynamics in Carolina bay wetlands. 

Wetlands. 28:17-27. http://www.srs.fs.usda.gov/

pubs/ja/ja_stroh001.pdf.

Figure 11. This image shows the bay in different phases. The photo to the left 

shows the bay in the driest period. The top right photo shows the bay in the 

between phase. The bottom right shows the bay in the wettest phase.

wetlands around the world 

might change over long 

periods of time. 

Over the next 30 to 60 

years, it is predicted that 

the world will experience climate 

change, likely changing annual rainfall. 

Climate change may decrease or increase 

rainfall. Although scientists 

do not know what will 

happen in the future, 

climate change could affect 

wetlands around the world. 

This study helps scientists 

understand what might 

happen to Carolina bays 

and wetlands like them as 

climate change occurs.
30

Ecosystem Services Edition • http://www.naturalinquirer.org 

FACTivity Take the large piece of fabric and place it on 

the ground. This area is the water in the wetland. 

Remember wetlands are not perfectly round, so 

students may cut the fabric to make the wetland 

into a unique (but somewhat round) shape. Have 

students chose a center point of the wetland and 

place the toilet plunger at this point.

The three pieces of looped string indicate 

the different vegetation zones. Each looped 

string will be placed on the “wetland,” around 

the center. The first zone from the wetland is the 

aquatic plants (the smallest loop), the second 

is the marshy plants (the next biggest loop), 

and the third is the woody plants (the largest 

loop). The zones should be somewhat concentric 

around the center pole, and the largest loop 

may go outside of the “wetland.” Scatter the 

appropriate color beans in the right zone. 

Divide the class into eight groups. Give 

each group a piece of string. Tell the groups 

to attach all eight pieces of string to the pole. 

Stretch out the string away from the pole like 

eight equal pieces of pie. Tell the students to 

place the paper plate rings at each knot in the 

string, with the center of the ring at the knot. 

(Compare with photo, page 21.) For the area 

closest to the pole, start at the second knot. 

Have the students count and record the number 

and color of the beans in each zone located 

within the ring. Each group will count the beans 

within six rings. One student will record the 

zone and the total number of beans found 

within all of the rings in each zone.

Repeat this exercise at least three times. To 

record observations provide each group with 

a copy of this chart. Remember, not every one 

of these boxes will be filled out. This should 

become clear as you do the FACTivity.

Time Needed: One class period; indoor 

or outdoor.

This FACTivity will represent the methods the 

scientists used to collect vegetation data in the 

study. The question students will answer in this 

FACTivity is: How well does sampling work to 

represent the entire population of something 

being studied?

Materials Needed:

• 200 dried beans (3 different colors: 80 

beans represent aquatic plants, 70 beans 

represent marshy plants, and 50 beans 

represent woody plants (NOTE: You are 

starting with 40-percent “aquatic” beans, 

35-percent “marshy” beans, and 25-percent 

“woody” beans. This will be important to 

remember later on!).

• 8 pieces of string or yarn, each 6’ long with 

knots or tape every foot.

• Three pieces of thin rope or thick string (one 

piece 20-25’, one piece 35-40’, and one 

piece 55-60’), with the ends tied to make 

three large loops.

• A toilet plunger. 

• A large piece of fabric, about 7-8’ square 

(an old sheet works well).

• 48 paper plates with the center cut out 

(leaving only about 1” so that the plate 

becomes a ring.

• Paper and pencil for recording data.

• Chart to record data (see below).

Think about the different types of plants in a 

Carolina bay wetland. Then think about how the 

scientists sampled areas in the Carolina bays. 

You will do something similar in this FACTivity. 
31

The Natural Inquirer • Volume 12 Number 1

Student Names:

Ring 

1

Ring 

2

Ring 

3

Ring 

4

Ring 

5

Ring 

6

Total 

Number

Aquatic

Zone

Marshy

Zone

Woody

Zone

Then, add the number of beans in each category from 

all eight groups and put the numbers in the chart below.

Aquatic Zone Marshy Zone Woody Zone

First Sampling

Second Sampling

Third Sampling

Total Number

Add the total number of beans that fell under all of the rings for each sampling. (Add the last 

row of the chart above and record the number below.) Then add across to get the total number.

Aquatic Zone Marshy Zone Woody Zone Total Number

Now calculate the percentage of each color of beans you found in your samples compared to 

the total number of beans in all of the samples. Write this in the table below. You will do this by 

dividing the total number found in the rings (from each zone, columns 1 to 3 from the chart above) 

in each zone by the total number of beans in all of the rings (column 4 from the chart above).

Aquatic Zone Marshy Zone Woody Zone

Now, compare the 3 percentages above with the original percentages. (You can find the 

percentages in the first line under “Materials” at the beginning of this FACTivity). How do the 

numbers compare? Did your sample percentages resemble the percentages of the population 

of beans? Why do you think this is so? Answer the question posed at the beginning of this 

FACTivity. Why do scientists often choose to take a sample of what they study and not identify or 

study every individual? If you continued to sample three more times, do you think your sample 

percentages would come closer to the population percentages? Why or why not?

String or Yarn

Fabric String or Rope:

Aquatic Zone

String or Rope:

Marshy Zone

String or Rope:

Woody Zone Paperplate rings

placed along string or

yarn (placed on all 8)

If you are a Project Learning Tree-trained educator, you may use activity #29, “Rain Reasons” 

and # 71, “Watch on Wetlands” as an additional resource. 

EPA’s Wetlands, Oceans, and Watersheds Kids’ Page

http://www.epa.gov/owow/kids.html

Additional	Web	Resources:

USGS’s National Wetlands Research Center

http://www.nwrc.usgs.gov/
32

Ecosystem Services Edition • http://www.naturalinquirer.org 

Predicting the

of Invasive Species

s p r e a d

Think Outside the Box
33

The Natural Inquirer • Volume 12 Number 1

Meet the Scientists

Dr. Tom	Crist, Terrestrial Ecologist: 

My favorite science experience 

was conducting field studies on the 

biodiversity of forest canopy insects 

in Ohio. 

Dr.	Bob	Parmenter, Wildlife Ecologist: My 

favorite science experience has been working 

on the Mount St. Helens volcano since its 

explosive eruption in 1980. In the early years 

after the eruption, the roads were destroyed. 

My crews and I helicoptered into our study 

sites, where we examined the diversity and 

population sizes of the surviving plant and 

animal species. Over the last three decades, 

we’ve returned many times to witness and 

record the remarkable recovery of the plants 

and animals. This recovery provides evidence 

of Nature’s resilience. I’m looking forward to 

going back in 2010 for the 30-year reunion 

of scientists that have worked there since the 

eruption—along with new generations of 

science students!

Dr.	Ariel	Lugo, Tropical Ecologist: My 

favorite science experience is trying 

to understand the functioning of 

natural ecosystems in collaboration

with bright people, including high 

school students.
34

Ecosystem Services Edition • http://www.naturalinquirer.org 

Glossary

biodiversity (bi o duh vür suh te): A measure 

of the differences between the types and 

numbers of living things in a natural area.

population (päp yoo la shun): The whole 

number of individuals of the same type 

occupying an area.

species (spe sez): Groups of organisms 

that resemble one another in appearance, 

behavior, chemical processes, and 

genetic structure. 

resilience (re zil yentz): The ability to 

recover from or adjust easily to change. 

collaboration (ku la bür a shun): Working 

together with others. 

data (da tuh): Facts or figures studied in 

order to make a conclusion.

invasive species (in va siv spe sez): Native 

or nonnative species that, by expanding 

their populations very rapidly, modify the 

environment and affect the economy or 

human health.

nonnative (nän na tiv): Not naturally 

occurring in an area.

economy (e kôn o me): A system of 

interactions and exchanges sometimes 

involving money.

ecosystem (e ko sis tem): Community 

of plant and animal species interacting 

with one another and with the nonliving 

environment. 

scale (skal): Distinct series of levels or 

measured areas.

invertebrate (in vür tuh bret): Lacking a 

backbone.

globalization (glob ul i za shun): Becoming 

more worldwide in scope.

Thinking About 

Science

Sometimes scientists 

examine existing data in 

a new way to figure out a 

problem or understand 

what should be done next. 

They might also look at the 

way other scientists have done 

research in the past to see if trying a new way 

might provide more useful information. One 

way scientists do these things is to read, discuss, 

and observe what has already been done. 

In this study, scientists wanted to better 

understand and predict the spread of invasive

species. Invasive 

species are usually 

nonnative species 

that change the 

environment, the 

economy, or human 

health. To make 

better predictions 

about where invasive 

species will spread, 

the scientists looked 

at how scientists 

currently predict the 

spread of invasive 

species. After the 

scientists studied 

how predictions are 

currently made, they 

made suggestions 

for improving the 

method. Making 

Pronunciation 

Guide

a as in ape

ä as in car

e as in me

i as in ice

o as in go

ô as in for

u as in use

ü as in fur

oo as in tool

ng as in sing

Accented syllables 

are in bold.
35

The Natural Inquirer • Volume 12 Number 1

more accurate predictions about the future 

will help scientists better understand the 

environment, manage ecosystems and the 

economy, and protect human health. No matter 

what they are studying, 

scientists always look 

for better ways to 

do their research.

Thinking 

About 

 the 

Environment

The scientists in this study were concerned 

with the spread of invasive species and 

their impact on the natural environment. To 

understand the spread of invasive species, the 

scientists needed to study the problem at many 

different levels in the natural environment. In 

science, we call the different levels scales. 

 Studying invasive species in a local 

community would be an example of a small 

scale study. In a small scale study, scientists 

study the habitat immediately surrounding 

the plant or animal. Studying invasive species 

by State, region, or the whole world would 

be a much larger scale study. As the scale of 

a study gets larger, less detail is examined. 

Environmental scientists sometimes focus on 

the larger scale to examine how large areas 

containing plants and animals interact with 

the land. Think of something you have studied 

in school that could be examined at several 

different scales.

What are Ecosystem Services?

 Ecosystem services result in benefits 

that people receive from ecosystems. 

Ecosystem services are often put into four 

categories. These categories are (1) those 

that provide, (2) those that regulate, (3) 

those that support, and (4) those that 

help people culturally. Ecosystem services 

that provide, for example, include the 

products of trees. This is because trees 

provide food, wood products, and fuel. 

Ecosystem services that regulate include, 

for example, processes that help slow the 

spread of invasive species. Supporting 

ecosystem services refer to things like the 

continual cycling of carbon and nitrogen 

from Earth to the atmosphere and back. 

This is because these elements support life. 

Cultural services are provided by places 

for educational or recreational activities, 

such as streams for canoeing. For more 

information on these four categories, read 

the “Welcome” at the beginning of this 

journal on page 6 or visit http://www.

fs.fed.us/ecosystemservices/About_ES/

index.shtml. 

In this research, the scientists wanted 

to do a better job of predicting the 

spread of invasive species. When invasive 

species spread to new areas, the plants 

and animals that naturally live there 

are affected and even die. The normal 

ecosystem services that these 

native plants and animals provide 

are then no longer available unless 

other organisms 

replace them. 
36

Ecosystem Services Edition • http://www.naturalinquirer.org 

People can now travel to most places 

because transportation has greatly improved. 

Countries can easily trade with many different 

countries across the planet. This process is 

called globalization. Globalization causes 

many things to happen. For the scientists 

in this study, globalization has increased 

the spread of invasive species. With more 

people, animals, and plants moving back 

and forth between places, it is easier for 

invasive species to move from place to 

place. If scientists can predict the spread of 

invasive species, the spread may be slowed 

or stopped. The question the scientists in this 

study wanted to answer is: How can scientists 

better predict the spread of invasive species?

Method

The method scientists used to study this 

problem was interesting and fun. About 

100 scientists met in New Mexico at a 

conference. The scientists met in small groups 

based on topics of interest. For example, 

some of the topics included hurricanes, sea 

level rise, and coastal wetlands. Each group 

of scientists decided to write papers about 

their own topic. Because the scientists lived 

all over the United States, they had to use 

technology to communicate with each other. 

The scientists communicated on the phone, in 

person, and through emails.

To answer their question, the scientists 

examined the research that had already 

been done on invasive species. The scientists 

examined the methods other scientists used to 

make predictions about the spread of these 

invasive species. When a particular example is 

studied, this is called a case study. An example 

of a case studied was the zebra mussel. 

The zebra mussel invaded the Great 

Lakes and has moved into rivers surrounding 

the Great Lakes (figure 1). The zebra 

mussel affects the lakes’ ecosystem in many 

ways (figure 2). Zebra mussels change the 

environment by disrupting food webs and 

causing native mussels to die. To predict the 

movement of a plant or animal such as zebra 

mussels, scientists sometimes create models of 

what might happen. These models are built 

on computers, and they represent what might 

happen in real life. Models are used to make 

predictions about many different things. When 

you see a prediction of the path that rain, snow, 

or a hurricane might take in the future, you are 

looking at the results of a computer model.

The scientists looked at many predictions and 

the computer models upon which they were 

based. Then, they worked together to evaluate 

which predictions were the most successful.

Introduction

Reflection Section • Think of one advantage of globalization 

for you or your community. Think of one 

disadvantage of globalization for you or 

your community. 

• In your own words, state the problem that 

the scientists wanted to study.
37

The Natural Inquirer • Volume 12 Number 1

Reflection Section • After reading the Method 

Section, how do you think 

technology helps scientists to 

work together? 

• Why do you think scientists 

examined a lot of different 

case studies before they 

made a decision about the 

best way to track the spread 

of invasive species?

Figure 2. The adult zebra mussel can attach itself to a 

boat. Sometimes the zebra mussel moves into a new area 

because it has attached itself to a boat. Photo courtesy of 

USGS, http://nas.er.usgs.gov/taxgroup/mollusks/images/

zebramussel9.jpg

Figure 1. The Great Lakes and the States that surround the 

Great Lakes. Do you live near the Great Lakes?

Findings

Five scientists worked together 

to develop a paper on invasive 

species. The scientists had different 

views on the spread of invasive species. The 

scientists had to have many discussions to come 

to an agreement about their different points 

of view. Each scientist had to think carefully 

and consider the ideas of the other scientists.

The paper the scientists wrote about 

predicting the spread of invasive species 

combines different ideas about invasive 

species into one story. Once the invasive 

species paper had been written, the 

paper was passed back and forth 

between all the scientists for 

editing and comments. 
38

Ecosystem Services Edition • http://www.naturalinquirer.org 

After the scientists agreed 

with what was written, the 

paper was sent out for peer 

review. Peer review is a 

process involving others who are 

considered an equal in knowledge or skill. In 

this case, other scientists read the paper and 

provided comments and suggestions. These 

other scientists had not been involved with 

the project before then, but they knew about 

invasive species. After this review, the paper 

was published in a journal.

In their paper, the scientists discussed 

their findings about predicting the spread 

of invasive species. The scientists found 

that some models of the spread of invasive 

species were more successful at prediction 

than others. They were more successful if 

they examined larger geographic scales. 

The scientists recommended that in the future, 

scientists should examine the spread of 

invasive species at all geographic scales. 

Discussion

The scientists who wrote this article on 

invasive species benefited from examining 

the issue of invasive species from different 

perspectives. Science benefits from lively 

discussion with different points of view on the 

same topic. Progress is made in science when 

different points of view can be combined into 

one story. The scientists had different ideas 

but were able to come to an agreement on 

how the spread of invasive species should 

be predicted. The efforts of these scientists 

allowed the study of ecosystem services and 

invasive species to advance. 

The importance of studying invasive 

species at different geographical scales 

was highlighted in the scientists’ paper. 

Understanding the impact of invasive species 

on the local level as well as the impact at 

a larger geographical scale is important. 

Examining the possible impact at the larger 

geographical scale will help scientists make 

better predictions. The scientists suggested 

that this larger geographical study needs 

to be a coordinated effort among scientists 

across the globe. 

Reflection Section • Think of a time when you benefited from 

a discussion with someone else. How did 

it help you? 

• Why do you think scientists want to 

more accurately predict the spread of 

invasive species?

Reflection Section • How do you think sharing different 

opinions on a topic would help scientists 

better understand invasive species? Use 

an example from your own life to help 

you explain. 

• Why do you think it is important for 

scientists to coordinate their efforts?

This article was adapted from Crowl, T.A.; Crist, T.O.; Parmenter, 

R.R.; Belovsky, G.; and Lugo, A.E. (2008). The spread of invasive 

species and infectious disease as drivers of ecosystem change. 

Frontiers in Ecology and Environment. 6(5): 238-246. Available 

online at http://www.fs.fed.us/global/iitf/pubs/ja_iitf_2008_

crowl001.pdf.
39

The Natural Inquirer • Volume 12 Number 1

FACTivity

In this activity, students will explore their 

schoolyard at different scales. The question 

students will answer is: 

What are the similarities and differences of 

the schoolyard ecosystem at different scales?

Materials	Needed:

Yarn/string, scissors, clipboard, paper

Examining Scale in the Schoolyard

Procedure:

Split students into 10 groups of three students 

each. These groups will study the schoolyard 

at different scales. Each group will measure 

an amount of string and cut it. Two groups 

will cut a 4 foot length of string or yarn. Two 

groups will cut an 8 foot length of string or 

yarn. Two groups will cut a 15 foot length of 

string or yarn. Two groups will cut a 30 foot 

length of string or yarn. Tie the ends of each 

length together, so that each group has a 

circular piece of string or yarn. You may need 

to adjust the sizes depending on the amount of 

outdoor area you have at your school. 

 Assign each group a notetaker and give 

them each a clipboard and paper.

Before heading 

outside, tell the 

students that they 

are to examine an 

area of land in the 

school yard that 

fits within the circle 

their yarn makes. Ask 

them to brainstorm categories of things they 

might find in the schoolyard. Examples include 

insects, plants, animals, nonliving natural 

things, and nonliving man-made items. 

 Each group will have 20 minutes to explore 

their area and make notes.

 Once students have had time to gather their 

information, they will present to the class what 

they found.

 As a class, create a four-column chart to 

write down what students found at different 

scales. Discuss the chart once all the columns 

have been filled in. Some discussion questions 

might include the following:

1.	 What	do	you	notice	about	the	items	that	

were	found	in	the	different	scales?		

2.	 What	are	some	similarities	and	

differences	between	what	people	found?

3.	 How do	you	think this activity

represents what scientists did in the

article we just read?

If you are a Project Learning Tree-trained educator, you may use PLT Activity #88, “Life on the Edge” as an 

additional resource. 

Additional	Web	Resources:

Zebra Mussel Distribution Map: http://www.nationalatlas.

gov/articles/biology/a_zm.html

Forest Service Ecosystem Services Page:

http://www.fs.fed.us/ecosystemservices/usgs.gov/

USGS Zebra Mussel Information Page:

http://www.glsc.usgs.gov/main.php?content=research_invasive_zebramussel&title=Invasive%20

Invertebrates0&menu=research_invasive_invertebrates
40

Ecosystem Services Edition • http://www.naturalinquirer.org 

Identifying Ecosystem Services of 

Small Wetlands on the American Prairie

Fill Those Potholes
41

The Natural Inquirer • Volume 12 Number 1

Meet the Scientists

> Dr. Robert Gleason, Research Wildlife 

Biologist: As a wildlife biologist I have had 

many memorable experiences conducting 

field work in wetlands, including studying 

soils, plants, aquatic insects and other 

animals, and especially waterfowl. The most 

rewarding aspect of my job, however, is when 

research results provide the scientific basis 

for sound management and conservation of 

wetland ecosystems. 

< Dr. Chip Euliss, Research Wildlife Biologist: I am a 

pretty lucky fellow because I’ve had many favorite science 

experiences over my career. Writing this to you is 

one of my favorites. This is because what I enjoy most 

about my job is helping teach people about science 

and how it can improve our lives. The information in this 

article will teach you about the important 

services that ecosystems 

provide to our society.

< Mr. Murray Laubhan, Ecologist: My 

favorite science experience is learning 

something new that helps land managers 

successfully restore wetlands.

^ Mr. Brian Tangen, Biologist: My favorite 

science experience involved canoeing and 

back-country camping in the boundary waters 

wilderness area in northern Minnesota. I did 

this to conduct research on bald eagle habitat.
42

Ecosystem Services Edition • http://www.naturalinquirer.org 

Glossary

wetlands (wet lendz): Areas of land with a 

lot of soil moisture.

aquatic (uh kwat ik): Growing or living in 

or upon water.

waterfowl (wä tür fowl): Birds that spend 

part or most of their life around or 

on water.

management (man ij ment): The conducting 

or supervising of something.

conservation (kän sür va shun): The care 

and protection of natural resources, such as 

forests and water.

ecosystem (e ko sis tem): Community 

of plant and animal species interacting 

with one another and with the nonliving 

environment.

habitat (hab uh tat): Environment where a 

plant or animal naturally grows and lives.

agency (a jen se): A separate unit of a 

government.

sustain (suh stan): To keep up or maintain.

natural resources (na cha rôl re sôrs es): 

A supply of something in nature that takes 

care of a human need, such as oil, forests, 

or water.

economic (e ko nom ik): Having to do 

with the management of money in a home, 

business, or government.

migratory (mi gruh tôr e): Having a 

characteristic of moving from one place 

to another.

breeding habitat (bre ding hab uh tat): 

Environment where an animal nests and 

reproduces as opposed to where it lives 

during the rest of the year.

Pronunciation 

Guide

a as in ape

ä as in car

e as in me

i as in ice

o as in go

ô as in for

u as in use

ü as in fur

oo as in tool

ng as in sing

Accented syllables 

are in bold.

diversity (di vür suh te): A measure of the 

differences between the types and numbers 

of living things in a natural area.

restore (re stôr): To put or to bring back 

into a past or original state.

policy (päl uh se): Overall plan with rules 

that must be followed, generally made by 

a government.

variable (ver e uh bul): A thing that can 

vary in number or amount.

nutrient (noo tre ent): Any of the substances 

found in food that are needed for the life 

and growth of plants and animals.

erosion (e ro zhen) The process or state of 

wearing or washing away.
43

The Natural Inquirer • Volume 12 Number 1

Thinking 

About 

Science

Most scientists, like most 

people, work as members 

of an organization. All organizations have a 

mission. A mission is similar to a goal. Everyone 

in the organization does their own job to fulfill 

the mission. Sometimes people in different 

organizations work with each other. They do 

this when what they are doing together helps 

each organization to fulfill its mission. 

Agency Mission

U.S. Department of the 

Interior, U.S. Geological 

Survey (USGS)

Serves the Nation by providing scientific information to:

1. Describe and understand Earth

2. Minimize loss of life and property from natural disasters

3. Manage water, biological, energy, and mineral resources

4. Enhance and protect the quality of life

U.S. Department of 

Agriculture, Farm Services 

Agency (FSA)

Handles farm, conservation, disaster, and loan programs to 

help farmers manage their land for economic health now and 

in the future.

U.S. Department of the 

Interior, U.S. Fish and 

Wildlife Service (FWS)

Works with others to conserve, protect, and enhance fish, 

wildlife, and plants and their habitats for the continuing benefit 

of the American people.

U.S. Department of 

Agriculture, Natural 

Resources Conservation 

Service (NRCS)

Helps people help the land through conservation programs.

In this study, the scientists worked for 

different United States agencies (figure 1). 

These agencies all work to use and sustain

the Nation’s natural resources. Even though 

the agencies all work with natural resources, 

their missions are different. When scientists 

work with scientists from other organizations, 

they can still help their own agencies fulfill 

their mission. They also save time and money 

by sharing the work. Whether or not you 

are a scientist, it makes sense to work with 

others when you can all achieve your goals 

by working together. As you read figure 1, 

compare each agency’s mission. How are the 

missions alike? How are they different?

Think of a time when you worked with others. Were you able to share the work? What 

qualities does a person need to work successfully with others? Do you think the scientists 

in this study had these qualities? Why or why not?

Figure 1. The U. S. agencies involved in this research.
44

Ecosystem Services Edition • http://www.naturalinquirer.org 

The Prairie Pothole Region of North America 

is an area of the northern Great Plains (figure

2). This area was once mostly made up of 

mixed grass and tallgrass prairies (figures 3

and 4). When the glaciers receded 10,000 

years ago in this area, they left millions of 

shallow depressions. These depressions filled 

with water and are now known as prairie 

potholes. These potholes 

are wetlands which provide 

a temporary home to 

over 50 percent of North 

America’s migratory

waterfowl. Most of the 

water found in prairie 

potholes comes from 

melting winter snow.

In this area of the United States, the soil is 

good for growing agricultural crops. In the past, 

farmers drained the potholes to increase 

the amount of land available to grow 

crops. Over half of the prairie potholes 

have been drained. This was not good for 

the waterfowl who depend on the potholes 

for breeding habitat, food, and shelter. 

Government programs now help farmers 

and landowners restore the prairie potholes 

to their wetland condition. As wetlands, the 

potholes do more than provide habitat for 

waterfowl. In this research, you will learn 

about other services provided to humans by 

prairie potholes. These services are known 

as ecosystem services. 

Thinking About the 

Environment

Figure 2. The Prairie Pothole Region of North America. 

Notice how this region goes into Canada. 

Figure 4. A tallgrass prairie. 

Figure 3. A mixed grass prairie.
45

The Natural Inquirer • Volume 12 Number 1

Ecosystem services are environmental 

benefits provided by natural areas. Ecosystem 

services are important to humans. Ecosystem 

services include things such as providing clean 

water, clean air, habitat for animals, a variety 

of plants, and healthy soil. It is believed that 

prairie potholes provide many important 

ecosystem services. 

Prairie potholes are small wetlands formed 

when melting snow runs into small depressions 

in the land (figures	5 and 6). In the past, many 

of these potholes were drained by farmers. 

The potholes were drained to increase the 

amount of land available to grow crops. The 

benefits of having more crops were thought to 

be more important than the benefits of having 

prairie potholes.

In 1985, the United States Department of 

Agriculture (USDA) started two nationwide 

programs to restore some types of land to 

their natural state. These programs help 

landowners and farmers in the Prairie Pothole 

Region restore the prairie potholes that were 

drained. The goal of these programs is to 

restore the ecosystem services that were lost 

when the potholes were drained.

Introduction

Figure 5. Prairie pothole. 

Figure 6. Prairie pothole. 

The Two Government 

 Programs

The Conservation Reserve Program 

(CRP) and the Wetlands Reserve Program 

(WRP) were established in the 1985 Farm 

Bill. The Farm Bill is the primary way that 

agricultural policies are determined by the 

Federal Government. The CRP encourages 

landowners to take cropland that is in 

environmentally sensitive acres and plant 

grasses or trees instead of crops. The 

WRP encourages landowners to restore 

wetlands in areas that had been drained 

and planted in crops. Landowners receive 

an annual rental payment for 10 to 15 

years. This payment makes up for the 

money they would have made from selling 

crops grown on that land. These programs 

are run by the Natural Resources 

Conservation Service, or NRCS. 

(See figure 1 to learn about 

NRCS’s mission.)

Number Crunches

How many years have the two government programs been in operation?
46

Ecosystem Services Edition • http://www.naturalinquirer.org 

Now that the programs have been in 

operation for many years, it was time to find 

out whether the programs are achieving their 

goal. The scientists in this study wanted to 

know whether some of the ecosystem services 

provided by prairie potholes are restored 

when the potholes are restored. They wanted 

to know how much benefit the restored prairie 

potholes provide to people, compared to the 

natural prairie potholes that had never been 

drained for crops. They also compared the 

restored potholes with nearby crop land.

Reflection Section • The United States Congress created 

two programs to help restore land to its 

natural state. By creating these programs, 

Congress recognized that some ecosystem 

services are at least as important as the 

services provided by agricultural crops 

or other uses of land. Review the list of 

ecosystem services in the first paragraph 

of the “Introduction.” You may also review 

“Thinking About the Environment” to learn 

about an important ecosystem service 

provided by prairie potholes. Do you 

agree that some of these services are as 

important as agricultural crops? Why or 

why not? 

• What are the questions the scientists 

wanted to answer? 

The scientists wanted to know about prairie 

potholes that had been restored. To restore 

prairie potholes, farmers and landowners 

removed unnatural drains and planted grasses 

and other plants in and around the potholes. 

The scientists studied 204 potholes in 1997 

and 270 pothole areas in 2004 (figure 7). The 

pothole areas included more than the pothole 

or wetland itself. The areas included the land 

around the pothole, which drained water into the 

pothole (figures 8 and 9). The restored potholes 

were surrounded by crop land (figure 10).

Method

Shoulder-slope

Shoulder-slope

Mid-slope

Mid-slope

Upland subzones Wetland subzones

Toe-slope

Toe-slope

Wet-meadow

Wet-meadow

Shallow-marsh

Shallow-marsh

Wetland catchment

zone

Wetland catchment zone

Overflow/spill

elevation Overflow/spill

elevation

Catchment

Upland catchment

zone

Upland catchment

zone

Deep-marsh

Deep-marsh

} }

}}

Figure 7. Areas studied in 1997 and 2004. The dots show 

the pothole areas that were studied.

Figure 8. Profile of a prairie pothole area. 
47

The Natural Inquirer • Volume 12 Number 1

When a restored pothole or a restored pothole 

area was identified, the scientists located the 

closest natural pothole to it. For each restored 

and nearby natural pothole area, scientists 

collected information about its soil, plants, and 

three-dimensional shape (figure 11). They also 

collected the most of the same information from 

nearby crop land.

The scientists then compared the 

information they collected at restored and 

natural potholes and pothole areas. They also 

compared this information with information 

collected at nearby crop land.

Figure 9. The profile of a prairie pothole using a 

photograph. Compare this to figure 8.

Figure 10. This restored prairie pothole is surrounded by crop 

land. Compare this prairie pothole with those in figures 5 & 6.

Figure 11. Some of the variables measured at each 

restored and natural prairie pothole or prairie pothole 

area. The scientists also measured some of these variables 

on nearby crop land.

Number Crunches

How many yards high is 2 meters? Multiply 

1.09 by 2 to find out. How many feet high 

is 2 meters? (Note: This measure told the 

scientists how much protection from plants was available for wildlife around the 

prairie pothole.)

Variable Measurement

Soils Nutrients (Carbon, Nitrogen, Phosphorus)

pH (A measure of how acidic or basic the soil is)

Type of soils in the area

Soil texture

Plants 

(vegetation)

Types and number of plants in 

the area

How much of the ground is covered by plants

The depth of the dead plant material on the 

ground

How much living and once-living plant material is 

found in the area

How thick the plants are from the ground to 2 

meters high

How wide each of the zones are (see figure 8)

Threedimensional 

shape

The size of the area in hectares

The physical shape and unevenness of the area

The volume of water in the pothole wetland

Reflection Section • Look at figures 7, 8, and 9. In 1997, 

the scientists collected information about 

potholes only. In 2004, they collected 

information about potholes and the land 

surrounding the pothole. Why do you think 

they expanded the study area around 

each pothole? 

• Why did the scientists compare restored 

prairie potholes to natural prairie potholes?
48

Ecosystem Services Edition • http://www.naturalinquirer.org 

The scientists reported on four ecosystem 

services. These services were (1) Providing 

a variety of plant species; (2) Helping to 

address climate change by holding carbon in 

the soil; (3) Holding rain and storm water in 

the potholes, thereby reducing the threat of 

flooding; and (4) Reducing soil erosion.

The scientists discovered that the variety of 

plants in restored potholes and pothole areas 

was not as great as the variety of plants in 

natural potholes and pothole areas. They 

found, however, that the variety of plants in 

restored potholes was greater than in nearby 

areas with crops.

The scientists were interested in how much 

carbon was being 

held in the soil of 

prairie potholes 

and pothole areas. 

When the soil holds 

carbon in the form of 

dead and decaying 

plant and animal 

matter, it prevents 

more carbon from 

going into the 

atmosphere. Carbon 

in the atmosphere 

contributes to global 

climate change. 

When soil holds 

carbon, therefore, 

it is considered an 

ecosystem service. 

Findings The scientists found that natural prairie 

potholes and pothole areas hold more carbon 

than either restored potholes or areas with 

crops. The scientists expected the soil of 

restored potholes to contain more carbon than 

areas with crops, but they did not find this to 

be the case.

The scientists were also interested in how 

well the potholes could prevent flooding in 

nearby areas. They estimated that all of the 

restored and natural prairie potholes in the 

United States could hold an amount of water 

equal to 56,500 hectares 1 meter deep. This 

equals 458,000 acres of water 1 foot deep 

(figure 12). The scientists concluded that prairie 

potholes provide a service to people because 

they can help protect people from floods.

Figure 12. An area of water covering 458,000 acres and 

1 foot deep. This is a little less than the area of the District 

of Columbia. 
49

The Natural Inquirer • Volume 12 Number 1

The scientists believe that much more 

research has to happen before they can 

identify and measure all of the ecosystem 

services provided by prairie potholes. They 

also believe that the CRP and the WRP 

have helped to provide ecosystem services 

to people. The programs have done this by 

encouraging farmers and landowners to 

restore some of their cropland back to prairie 

potholes and pothole areas.

Discussion

Figure 13. A comparison of the ecosystem services 

provided by natural prairie potholes, intensive crop land, 

and crop land with restored prairie potholes. Adapted 

from rs.resalliance.org/wp-content/tradeOff.jpg.

The scientists also discovered that soil 

erosion was reduced in the restored prairie 

potholes as compared to land with crops. One 

of the greatest benefits of reduced soil erosion 

is that the pothole wetlands do not fill with soil. 

They can, therefore, remain pothole wetlands 

and continue to provide all of the services 

listed above (figure 13). 

Reflection Section • Based on the findings reported by the 

scientists, do you think prairie potholes 

provide valuable ecosystem services to 

people? Why or why not? 

• The scientists reported on four ecosystem 

services. Based on your reading of this 

article, what is one other ecosystem 

service provided by prairie potholes and 

pothole areas? 

Reflection Section • Based on the findings of this research, 

what is another research question the 

scientists could ask about prairie potholes 

and prairie pothole areas? (Hint: Reread 

the findings having to do with carbon and 

climate change.) 

• Do you agree that the CRP and the 

WRP have helped to provide ecosystem 

services? Why or why not?

Adapted from: Gleason, R.A.; Laubhan, M.K.; and Euliss. N.H. Jr.; 

eds., 2008. Ecosystem services derived from wetland conservation 

practices in the United States Prairie Pothole Region with an 

emphasis on the U.S. Department of Agriculture Conservation 

Research and Wetlands Reserve Programs: U.S. Geological 

Professional Paper 1745, 58 p. http://pubs.usgs.gov/

pp/1745/pdf/pp1745web.pdf.
50

Ecosystem Services Edition • http://www.naturalinquirer.org 

FACTivity 5 minutes:

As a class, discuss the term “ecosystem 

services” and what it means. If you have 

not done so before, read “Welcome to the 

Ecosystem Services Edition of the Natural 

Inquirer” on page 6. Before continuing, 

students should understand what ecosystem 

services are in a broad sense. In other words, 

students should understand that all natural 

areas provide at least one ecosystem service, 

or environmental benefit, to humans. Some of 

them provide many ecosystem services.

15 minutes:

Each pair (or group) of students will have 

an article and a blank piece of lined paper 

and a pencil. The pair (or group) should write 

their names and the article title on the top 

of the paper. Each pair will read only the 

following article sections: Thinking About the 

Environment, Introduction, Method, Findings, 

Discussion. Students should read the article 

aloud, rotating paragraph by paragraph.

10 minutes:

Each group will identify as many ecosystem 

services as possible found in their article. 

Note that these services may not be identified 

as such in the article. Students should use 

their imagination to identify more than one 

ecosystem service. One student will write 

these ecosystem services in a list, using this 

example format:

Time Needed: One class period

Materials Needed:

Visit http://www.naturalinquirer.org and print 

one each of the following articles:

Urban Forest Edition: (1) What you see is not 

what you get, (2) I’ve got you covered, (3) 

Good to the last drip, (4) Yard sale!, (5) Social 

groupies, (6) Balancing act.

Wilderness Benefits Edition: (1) Wilderness 

makes sense, (2) Elemental, my dear! (3) Can 

you hear me now? (4) Speakological, (5) As 

the frog hops.

Students will divide into pairs.

(These 11 articles should be enough for each 

pair of students to have their own article. If 

all of these articles cannot be printed, select 

enough so that the class is in groups of three 

to four and each group has its own article. 

More than one pair of students can read the 

same article.)

Each pair (or group) should have a blank 

piece of lined paper and a pencil. 

The question you will answer in this FACTivity 

is: What are other ecosystem services 

provided by the Nation’s natural resources? 

The method you will use to answer the 

question is:
51

The Natural Inquirer • Volume 12 Number 1

If you are a Project Learning Tree-trained 

educator, you may use #71, “Watch on Wetlands” 

as an additional resource. 

Additional	Web	Resources:

Scientific American podcast on ecosystem services, 60-second Earth:

http://www.sciam.com/podcast/episode.cfm?id=why-ecosystem-services-matter-09-02-05

Ecological Society of America: Ecosystem Services: A Primer:

http://www.esa.org/ecoservices/comm/body.com.fact.ecos.html

Forest Service Ecosystem Services:

http://www.fs.fed.us/ecosystemservices/

1. When fruit bats eat fruit, they later 

defecate the seeds at a place far away from 

where they ate the fruit. A new fruit tree 

may then grow. This is an ecosystem service 

because fruit bats help to spread the seeds 

of fruit trees and, therefore, enable new fruit 

trees to grow in new places.

10	minutes:

Students will share their list of ecosystem 

services with the class. Hold a class discussion 

about the types of services provided by 

the natural environment. Do the services 

identified provide important benefits? Why 

or why not?

Students should turn in their sheets to the 

teacher. The sheets can be used for assessment.

For homework, 

students will 

observe the 

natural land (and 

water) around 

them and identify 

as many ecosystem services as possible. 

Students can start with the schoolyard, 

looking out of the bus or car window, observe 

while they are walking, or explore the area 

around their home. The ecosystem services 

should be identified in written form, using 

the format given above. In class, using a 

rapid-fire format, students will share their 

observations. Students should consider all 

they have learned about the environment to 

identify ecosystem services. Students may be 

assessed on the number of ecosystem services 

identified, and the clarity and correctness of 

written expression.

FACTivity 

Extension
52

Ecosystem Services Edition • http://www.naturalinquirer.org 

Ecosystem Services Crossword Puzzle

Across

5. Community of plant and animal species interacting 

with one another and the nonliving environment

6. Plant life

9. To keep up or maintain

10. Plants growing or living upon water

12. A bird that spends part or all of its life around or 

on water

13. Working together with others

15. The ability to recover from or adjust easily 

to change

16. The process or state of wearing or washing away

18. Flat land area next to a stream or river

19. Thing that can vary in amount or size

20. Groups of organisms that resemble one another 

in appearance, behavior, chemical processes and 

genetic structure

Down

1. A method used by scientists to group or 

categorize species of organisms

2. The whole number of individuals of the same type 

occupying an area

3. The conducting or supervising of something

4. The process of change in some animals from an 

immature stage to an adult stage

7. An area of land whose soil is wet either all the 

time or seasonally

8. The quality of being different or varied

11. The care and protection of natural resources such 

as water and forests

14. Moving from one place to the next periodically

17. Facts or figures studied in order to make 

a conclusion

1

2

3 4 5

6 7

8 9

10

11 12

13

14

15

16

17

18 19

20
53

The Natural Inquirer • Volume 12 Number 1

1. A separate unit of government

2. Occurring every year

3. A measure of differences between the types and 

numbers of living things in a natural area

4. The care and protection of natural resources such 

as water and forests

5. Occurring in a pattern that typically happens 

again and again

6. A period of dry weather with little or no rain

7. Having to do with management of money in a 

home, business, or government

8. Water source that has a low amount of salt 

concentration

9. Environment where a plant or animal naturally 

grows or lives

10. The upper streams that contribute water to another 

source of water such as a river 

A H Z P B P H

O J M X O A S Z C U Z D

W Q X W I A L E B C R E U N D H P L

X C Q T O L Z I A O E F O R B B O U

G O V F E Z T W C F J E P N O S B W E K

O M E G N E O H N Y A N N U A L Q U E I

B T E E X I R N C U C B Z A G E N C Y W U J

G J U F B Q O Q J O L Z T H L D J T M H M L

U T N E I R T U N O I T A T E G E V X Z

H N L O Y S S V O C A T T M P

Z D V E A S T A P

U J S L I R R I R K L M D

Y R G J I Q V B B U Z Y V Q Y

H S R E T A W D A E H Q S B T N K W J

G K P R G K E T H T F R E S H W A T E R P

B K Y M U T I A R I N R S C X G H X F X W

V Z B A E L U U E O T N I O S H C X S M B

G D U F A A N V M N L A G T N K A D C D M

T U M N D T N O B W M I Y K Y O Q H L Z P

A I D O J I S I I R X R O I M O D E L

K K X R U O X D Y L Q U J I J Q S

T K T M N U Y M X Y P C F

J C Y V O I L R U

A N Z

Ecosystem Services Word Search

11.Lacking a backbone

12. A simplified example of a system in science

13. Not naturally occurring in an area

14. Any of the substances found in food that are 

needed for the life and growth of plants 

and animals

15. Overall plan with rules that must be followed 

generally made by a government

16. The act of controlling according to a system

17. To put or bring back into a past 

original state

18. Distinct series of levels or 

measured areas

19. Plant life

20. An area of land whose soil is 

wet either all of the time 

or seasonally
54

Ecosystem Services Edition • http://www.naturalinquirer.org 

The mission of the Forest Service is to sustain the 

health, diversity, and productivity of the Nation’s 

forests and grasslands to meet the needs of present 

and future generations. For more than 100 years, our 

motto has been caring for the land and serving people. 

The Forest Service, U.S. Department of Agriculture 

(USDA), recognizes its responsibility to be engaged in 

efforts to connect youth to nature and to promote the 

development of science-based conservation education 

programs and materials nationwide. 

This Ecosystem Services edition of the Natural 

Inquirer combines research done by the Forest Service 

and the USGS (U.S. Geological Survey). The mission 

of the USGS is that of serving the Nation by providing 

reliable scientific information to describe and 

understand Earth; minimize loss of life and property 

from natural disasters; manage water, biological, 

energy, and mineral resources; and enhance and 

protect our quality of life.

The Natural Inquirer is a science education resource 

journal to be used with learners from grade 5 and 

up. The Natural Inquirer contains articles describing 

environmental and natural resource research 

conducted by Forest Service and USGS scientists 

and their cooperators. These are scientific journal 

articles that have been reformatted to meet the needs 

of middle school students. The articles are easy to 

understand, are aesthetically pleasing to the eye, 

contain glossaries, and include hands-on activities. 

The goal of the Natural Inquirer is to stimulate critical 

reading and thinking about scientific inquiry and 

investigation while learning about ecology, the natural 

environment, and natural resources. In this edition 

of the Natural Inquirer, you will find four articles on 

ecosystems written in the scientific method format. 

The Format of a Natural Inquirer Article:

Each Natural Inquirer article follows the same format. 

Natural Inquirer articles are written directly from a 

published science article, and all have been reviewed 

by the scientists for accuracy. Each article contains 

Note to Educators the following sections, which you may 

introduce to your students as they read: 

Meet the Scientists:

Introduces students to the scientists 

who did the research. This section may be used in a 

discussion of careers in science. 

Glossary:

Introduces possibly new scientific or other terms to 

students. The first occurrence of a glossary word is 

bold in the text.

Thinking About Science:

Introduces something new about the scientific process, 

such as a scientific habit of mind or procedures used in 

scientific studies.

Thinking About the Environment:

Introduces the environmental topic being addressed in 

the research.

Introduction:

Introduces the problem or question being addressed 

by the research.

Method:

Describes the method used by the scientists to collect 

and analyze their data.

Findings:

Describes the results of the analysis.

Discussion:

Discusses the findings and places them into the context 

of the original problem or question.

Citation:

Gives the original article citation with a Web link to 

the original article.

Science Education Standards and Evaluations:

In the back of the journal, you will find a matrix that 

enables you to identify articles by the national science 

education standards that they address. Evaluation 
55

The Natural Inquirer • Volume 12 Number 1

forms for both educators and students are available 

on our Web site. We welcome any feedback so 

please visit http://www.naturalinquirer.org and 

complete the online evaluation forms. Additionally, you 

may contact Dr. Barbara McDonald at the address 

below with any comments you have. 

Dr. Barbara (Babs) McDonald

Forest Service

320 Green St.

Athens, GA 30602-2044

706.559.4224

bmcdonald@fs.fed.us

(Please put “Educator Feedback” in the subject line)

Educator Resources:

Visit the updated Natural Inquirer Web site at 

http://www.naturalinquirer.org.

From this site, you can read and download lesson 

plans, word games, and other resources to help you 

use the Natural Inquirer in your classroom. You can 

also view and download a yearlong lesson plan 

aimed at helping your students learn about the 

scientific process.

Visit the Natural Inquirer Web site at 

http://www.naturalinquirer.org.

Lesson Plan for Ecosystem 

Services Edition

Materials and Supplies:

• Natural Inquirer Ecosystem Services Edition

• Copies of graphic organizer

National Science Education Standards Addressed:

Content Standards A, C, F

A. Abilities Necessary To Do Scientific Thinking

A. Understanding About Scientific Inquiry

C. Structure and Function in Living Systems

C. Regulation and Behavior

C. Populations and Ecosystems

G. Science as a Human Endeavor

G. Nature of Science

Time Needed: Two class periods

Class Period 1:

1. Pass out the Ecosystem Services Edition of the 

Natural Inquirer. As a class, read the “Welcome to 

the Ecosystem Services Edition” and preview the 

table of contents. 

2. Divide students into four groups and assign each 

group one article. (If you prefer smaller groups, 

divide students into eight groups and two groups 

will be assigned to one article.) 

3. Tell students that they are responsible for reading 

their article and completing the graphic organizer. 

Each person in the group is responsible for 

completing the graphic organizer. These graphic 

organizers will be used to present the article to the 

class the following class period.

4. Before students begin their assignment also share 

with them the rubric you will use to grade their 

work. Make sure students are clear about your 

expectations before they begin their work.

5. Give students the remainder of the class to read the 

article and fill out the graphic organizer.

Class Period 2:

1. Ask students to get out their graphic organizers 

and get into their groups. Allow the students 10 

minutes to review what they did yesterday within 

their groups and prepare to speak to the rest of 

the class.

2. Once students are prepared, have groups share 

what they learned from their article.

3. After students have finished sharing about their 

articles, ask students to go back to their groups and 

reread the “Welcome to the Ecosystem Services 

Edition.” While reading this section, ask students 

to think about how their article fits into the topic of 

ecosystem services. 

4. On a piece of paper, students should briefly 

answer this question: Why was my article chosen 

for the Ecosystem Services Edition?

5. Once all students have had a chance 

to answer this question, come together 

as a class and discuss how the articles fit 

into the topic of ecosystem services.
56

Ecosystem Services Edition • http://www.naturalinquirer.org 

Natural Inquirer Ecosystem Services Graphic Organizer

Introduction

Method

Findings

Discussion

In one or two sentences summarize the main idea of each section listed below.

In one or two sentences summarize the main idea of each section listed below.

Thinking About Science Thinking About the Environment
57

The Natural Inquirer • Volume 12 Number 1

Rubric For Ecosystem Services Edition

Unsatisfactory

1

Needs Improvement

2

Satisfactory

3

Exemplary

4

Score

Graphic Organizer Did not make 

attempt to fill out 

graphic organizer

Filled out half of the 

graphic organizer

Filled out most of the 

graphic organizermissed only 1 section

Completed the 

graphic organizer

Understanding of 

Material

Did not demonstrate 

understanding of 

material

Limited 

understanding 

demonstrated

Demonstrated 

understanding of 

material

Added extra 

evidence to show 

understanding of 

material

Grammar/

Punctuation

More than 8 errors 4-8 errors 1-3 errors No errors

Final Question Did not demonstrate 

understanding of 

material

Limited 

understanding 

demonstrated

Demonstrated 

understanding of 

material

Added extra 

evidence to show 

understanding of 

material

Score

Materials:

1. Natural Inquirer Ecosystem Services Edition 

2. Access to the Internet

Time needed: One class period

The purpose of this activity is to encourage students 

to critically think about how land cover, such as trees, 

water, pavement, and grasses, provides ecosystem 

services. The students will use an interactive map from 

the Internet to identify land cover and its associated 

ecosystem services anywhere in the United States. 

This activity works best if students are already 

familiar with ecosystem services. Review “Welcome 

to the Ecosystem Services Edition” and at least one of 

the following articles in the Ecosystem Services Edition: 

“Fill those potholes!” or “What goes around comes 

around.” Discuss the idea of ecosystem services with 

your students.

1. Have students form groups of three or four students 

each. Each group should have access to the Internet. 

Optional Internet Lesson Plan

Go to http://www.nationalatlas.gov and click MAP 

MAKER. (Note: If you have only one computer 

available, do this exercise with the entire class.) 

2. The screen should show a map of the United States. 

Students will access different features located 

on the right of the screen. First, add CITIES AND 

TOWNS and COUNTIES by clicking in the boxes 

by each. STATES should already be selected. Then 

click “redraw the map.” This tab is located on the 

top of the features box. After any item has been 

selected or deselected you must redraw the map 

to view the changes. Students should decide where 

in the United States they would like to focus. The 

next steps require zooming in on one area of the 

United States. This can be as large as a State, 

county, city, or a smaller area. Ideally 

different groups should select different 

size areas. If that happens, you have 

the additional option of holding a class 

discussion of how viewing a land cover 

map at different scales affects 

what you are able 
58

Ecosystem Services Edition • http://www.naturalinquirer.org 

to understand about land cover 

and ecosystem services. 

3. Once students 

have chosen an area, 

it is best if they 

deselect (or unclick 

the boxes) CITIES 

AND TOWNS and 

COUNTIES. They can 

then redraw the map, and 

city, town, and county names will disappear. Now 

click “Basic maps” to close this option. Click the 

BIOLOGY feature. Below invasive species, find and 

click the box beside LAND COVER RESOLUTION 

200 and redraw the map. The map should now 

show different colors that represent different land 

cover types in the area they have chosen to study. 

Click on BIOLOGY to close this option. 

4. Have students click on WATER. Then click in the box 

beside STREAMS AND WATERBODIES. Close the 

water option. Students should again redraw their 

maps. Their screen will show a map of their area 

with all land cover categories color-coded, with 

streams and other water bodies visible. 

5. Explain to students that land cover is the physical 

material at the surface of Earth. Land covers 

include grass, asphalt, trees, bare ground, water, 

etc. Each type of land cover has associated 

ecosystem services. Tell students that they will next 

think about what kind of ecosystem services are 

provided by the land cover and water within their 

map area. 

6. Students need to be able to view the land cover 

key. To view the land cover key, click “map key” at 

the bottom of the map or in the top right tab. The 

land cover types and colors should be visible on 

the right. 

7. Now the students are ready to explore the 

ecosystem services provided by the land cover 

types on their maps. Students may want to zoom 

in closer by clicking on the location on the map. 

Students can zoom out by clicking the area on the 

top of the map that says “zoom out.” 

8. Have students identify the different land covers 

and waters in their map area by using the map key 

and the ecosystem services key provided on page 

59. Students should explore by discussing what kind 

of land cover (and water) is found on their map. 

Using the Ecosystem Services Key below, students 

should begin to list the possible ecosystem services 

provided by the area on their map. Students may 

have additional ideas about the ecosystem services 

provided by the area. Each person in the group 

should write a paragraph about the ecosystem 

services provided by the land cover on their map. 

Each student should select at least three ecosystem 

services about which to write. You may use the 

rubric located at the end of the lesson plan to 

assess each student’s progress with the activity.

As an option, once students have “drawn” their 

maps on the screen, they may print them 

by clicking “Print map” at the top. They 

should enter a map title and follow 

instructions to print. 
59

The Natural Inquirer • Volume 12 Number 1

11.	 Mixed forest: Provides food, shelter, and habitat 

for animals. Some cover is available to animals 

all year long. Wood can be harvested to make 

homes and other products. Leaves fall to the 

ground and provide nutrients to the soil.

12.	 Shrubland: Food, shelter, and habitat for animals. 

Soil erosion is reduced because plants hold the 

soil together.

13.	 Orchards and vineyards: Insects and birds use 

the edge for shelter and look for food. Shelter is 

available for small mammals.

14.	 Grasslands/herbaceous: Grazing habitat for 

different animals. Habitat for insects and small 

mammals. The plants reduce soil erosion.

15.	 Pasture/hay: Grazing habitat for different 

animals. Habitat for insects and small mammals. 

The plants reduce soil erosion. People can use the 

hay for livestock and can sell the hay for money.

16.	 Row crops: Insect and songbird habitat. A source 

of food for people. Some wild animals will also 

eat the crops.

17.	 Small grains: Songbird, small mammals, and 

people food sources. 

18.	 Fallow: Habitat and food source for insects, 

songbirds, and mammals.

19.	 Urban/recreational grasses: Insect and songbird 

habitat. Some small mammals may use this area 

for habitat. 

20.	 Woody wetlands: Great habitat for many 

different animals—ducks, amphibians, reptiles, 

and mammals. Many animals will use this area to 

raise their babies. Source of water for animals. 

Wetlands filter the water to keep it clean and to 

reduce flooding in the areas.

21.	 Emergent herbaceous wetlands: Great habitat 

for many different animals—ducks, amphibians, 

reptiles, and mammals. Many mammals will eat 

the plants that grow in this area.

1.	 Water: Water provides aquatic species habitat, 

food, and shelter. Water also provides drinking 

water for humans and animals and water for 

plants. People may use the waterways as a way 

to get from one place to another.

2.	 Perennial ice and snow: Provides fresh water for 

plants and animals.

3.	 Low-intensity residential: Provides edge habitat 

for birds, small mammals, and insects. Open areas 

maybe used by predators to find prey.

4.	 High-intensity residential: Some insects and a 

few songbirds or other birds may be found in the 

area. Some small mammals may find shelter in 

houses or in other buildings. 

5.	 Commercial/industrial/transportation:

A few birds may nest in the buildings 

or bridges.

6.	 Bare rock/sand/clay: Different minerals come 

from each material. Some plants and animals 

only live on, under, or around rocks. Bare rock 

provides a place for reptiles to bask in the sun.

7.	 Quarries/strip mines/gravel pits: Large pools 

of water can form in quarries after a rain and 

provide temporary water 

for animals. 

8.	 Transitional: This area provides food 

and shelter for many different types 

of animals.

9.	 Deciduous forest: Provides food, shelter, and 

habitat for a wide variety of animals. Wood can 

be harvested to make homes and other products. 

Leaves fall to the ground and provide nutrients 

to the soil. Soil erosion is reduced in deciduous 

forests. Trees also take in and hold carbon, which 

reduces the amount of carbon dioxide in the 

atmosphere.

10.	 Evergreen forest: Provides food, shelter, and 

habitat for animals. Cover is available to animals 

all year long. Wood can be harvested to make 

homes and other products. Trees also take in and 

hold carbon, which reduces the amount of carbon 

dioxide in the atmosphere. 

Ecosystem Services Key
60

Ecosystem Services Edition • http://www.naturalinquirer.org 

Alternative: Students 

who have access to 

the Internet at home 

may be assigned 

this for homework. 

Go through the 

steps in class 

prior to making 

the assignment 

so students know 

what to do. You 

may want to make 

copies of the numbered instructions and the ecosystem 

services key for their reference. If you take this 

alternative, have students print their maps at home. 

Hold a class discussion the following day and have 

students share their maps and their paragraphs. 

Unsatisfactory

1

Needs Improvement

2

Satisfactory

3

Exemplary

4

Score

Map Maker Did not make 

attempt to follow 

map directions

Filled out half of the 

map directions

Filled out most of 

the map directionsmissed only 1 section

Completed the map 

directions

Understanding of 

Material

Did not demonstrate 

understanding of 

material

Limited 

understanding 

demonstrated

Demonstrated 

understanding of 

material

Added extra 

evidence to show 

understanding of 

material

Grammar/

Punctuation

More than 8 errors 4-8 errors 1-3 errors No errors

Final Question Did not demonstrate 

understanding of 

material

Limited 

understanding 

demonstrated

Demonstrated 

understanding of 

material

Added extra 

evidence to show 

understanding of 

material

Score

Toad-ally Awesome!

Introduction

What was the question the scientists wanted to 

answer? How does flooding affect the reproduction of 

toads in the forests along the Rio Grande?

How do you think flooding affects the reproduction of 

toads? This is an individual question and students should 

back up their opinions with logic, evidence, and reason.

Method

Why did the scientists also measure the amount of 

rainfall and the amount of water flow at each of the 

sites? The scientists needed to measure these things 

because the amount of rainfall and the amount of 

water flow help the scientists determine whether the area 

flooded or not.

Why do you think the scientists conducted their 

experiment from June through September of each 

year? This is an individual question. Possible answers 

Reflection Section Answer 

Guide
61

The Natural Inquirer • Volume 12 Number 1

Method

How do you think changes in rainfall affected the 

aquatic plants, marsh plants, and woody plants around 

the wetland? Students may have different answers, 

which are encouraged as long as they can back up their 

answer with logic and evidence. Depending on which 

vegetation type the student focuses on, the amount of 

rainfall influences which plant can survive. If a lot of 

rain has fallen, then the bay should contain a lot of 

water that would encourage aquatic plants to grow, etc.

An ecosystem is a very fragile system. When something 

disrupts the balance, the ecosystem may take years to 

recover. Do you think rainfall only affects vegetation in 

the current year or can rainfall affect how vegetation 

grows the next year? Explain. Students may have 

different answers which are encouraged as long as they 

can back up their answer with logic and evidence. The 

scientists found that it can take more than a year for the 

bays’ water levels to recover from a drought period. 

This means that vegetation patterns also take a while to 

change. The amount of water available will determine 

which plants grow in an area. 

Findings

How is the pattern of a person’s development similar 

to or different from a Carolina bay? Carolina bays 

are cyclical and people change in a directional pattern. 

Carolina bays can change back and forth from dry 

vegetation patterns, margin vegetation patterns, and 

aquatic vegetation patterns. People follow a directional 

model: baby, child, teenager, adult, etc.

How do you think aquatic plants return to the bay 

after a drought period? Plants put out seeds that are 

very strong and can survive without growing into a plant 

right away. Once environmental conditions are right, 

then the seed can begin to develop into a plant. For 

example, sometimes seeds have mechanisms 

that start germination, like a certain 

temperature and moisture. If it is too dry 

one year, the seeds might not germinate that 

year and wait for the right conditions in the 

next year. 

would be because it is reproduction season, rain season, 

and snow melt. 

Findings

Look at figure 6. Do you think flooding affected the 

reproduction of toads? Why or why not? It appears 

that flooding does affect the toad population because 

the scientists captured many more toads where there 

was flooding. 

What other living things do you think might be 

affected by flooding? Why? This is an individual 

question. Possible answers include other amphibians and 

their reproduction cycles, insects, plants, and predator/

prey relationships. 

Discussion

Do you think it would be a good idea to purposely 

flood the bosque periodically? Why or why not? 

Yes, because small floods could be safely managed to 

protect both the people and the toad populations. 

Would people benefit from flooding that would 

enable the toads to reproduce? Why or why not? This 

is an individual question and students should back up 

their opinions with logic, evidence, and reason.

What Goes Around Comes 

Around

Introduction

What would happen to the Carolina bays if the 

directional model were correct? What would happen 

if the cyclical model were correct? According to the 

directional model, the aquatic ecosystem might change 

into a marsh and then into a swamp (a forested wetland) 

because of prolonged drought that alters the vegetation 

to resemble more of a forested wetland than an aquatic 

wetland. According to the cyclical model, the bays 

always return to their aquatic ecosystem. 

What question did the scientists ask? After a period 

of prolonged drought, do Carolina bays become 

more forested or do they always return to their 

aquatic ecosystem?
62

Ecosystem Services Edition • http://www.naturalinquirer.org 

Discussion

How could climate change affect wetlands? There are 

no right or wrong answers to this question. Scientists are 

still trying to understand this question. If climate change 

makes more rainfall, then more wetlands and aquatic 

systems may occur in an area. If less rain falls, then 

wetlands may become a lot drier and change to swamps 

or even to forests with upland trees. This would change 

the wetlands’ job in the ecosystem.

What would happen if all the Carolina bays dried up 

completely? How do you think this would affect the 

surrounding ecosystem? Think about plants, animals, and 

humans. Refer to the “Thinking about the Environment” 

section. Wetlands provide a home to many unique plants 

and animals and perform many important roles to keep 

the environment healthy. For example, if the bays dried 

up, animals that feed on the aquatic plants would have 

to look somewhere else to get the right food sources.

Think Outside the Box

Introduction

Think of one advantage of globalization for you 

or your community. Think of one disadvantage of 

globalization for you or your community. There will be 

a variety of answers to this question. Encourage students 

to explain why they think their answer represents 

an advantage or disadvantage. Some examples of 

advantages include increased trade and access to a 

variety of products to buy. Some disadvantages include 

jobs being moved out of the community to other places 

and the increase in invasive species. 

In your own words, state the problem that the scientists 

wanted to study. The problem scientists wanted to study 

is how to better predict the spread of invasive species. 

Method

After reading the Method Section, how do you think 

technology helps scientists to work together? Scientists 

use technology to communicate, such as by the telephone 

and email. They also use the computer to examine 

different case studies, including the computer models 

that were used to make predictions.

Why do you think scientists examined a lot of different 

case studies before they made a decision about the 

best way to track the spread of invasive species? If 

the scientists had only used one or two case studies, 

they would not have much to compare. They needed to 

compare successful with unsuccessful predictions. For that 

they needed more than just one or two case studies.

Findings

Think of a time when you benefited from a discussion 

with someone else. How did it help you? This is an 

individual question and students will have many different 

experiences to share. In all cases, students should be 

able to identify how they benefited from having a 

discussion with someone else.

Why do you think scientists want to more accurately 

predict the spread of invasive species? Because when 

invasive species spread, they affect ecosystem services. 

This means they change the benefits provided to people 

by ecosystems.

Discussion

How do you think sharing different opinions on a 

topic would help scientists better understand invasive 

species? Use an example from your own life to help 

you explain. Because the scientists had different areas 

of expertise, their combined thoughts and ideas made 

for a much more complete understanding of how the 

spread of invasive species might be better predicted. 

Why do you think it is important for scientists to 

coordinate their efforts? It is important for scientists to 

coordinate their efforts so that they do not waste time 

duplicating efforts and so that they work most efficiently.

Fill Those Potholes!

Introduction

The United States Congress created two programs to 

help restore land to its natural state. By creating these 

programs, Congress recognized that some ecosystem 

services are at least as important as the services 

provided by agricultural crops or other uses of 

land. Review the list of ecosystem services in the first 
63

The Natural Inquirer • Volume 12 Number 1

paragraph of the “Introduction.” You may also review 

“Thinking About the Environment” to learn about an 

important ecosystem service provided by prairie 

potholes. Do you agree that some of these services 

are as important as agricultural crops? Why or Why 

not? This is an individual question and must be answered 

by each student individually. Students should be able 

to back up their reasoning with logic. You may use this 

question in a class discussion of the tradeoffs between 

agricultural and environmental (or ecosystem) services 

and benefits.

What are the questions the scientists wanted 

to answer? Do restored prairie potholes provide 

ecosystem services? If so, how what kind of services and 

how much benefit do they provide as compared to the 

natural prairie potholes that had never been drained? 

How do they compare in these services to nearby areas 

planted in crops?

Method

Look at figures 7, 8, and 9. In 1997, the scientists 

collected information about potholes only. In 2004, 

they collected information about potholes and the 

land surrounding the pothole. Why do you think they 

expanded the study area around each pothole? This is 

an individual question. Students will have to think of why it 

would be more advantageous to collect information from 

the land draining water into the pothole in addition to the 

pothole wetland itself. Students should be encouraged to 

explore the advantages of studying the larger area.

Why did the scientists compare restored prairie 

potholes to natural prairie potholes? The scientists’ 

questions were: Do restored prairie potholes provide 

ecosystem services? If so, how much benefit do they 

provide as compared to the natural prairie potholes that 

had never been drained? The scientists could not answer 

the second question unless they compared restored 

potholes with natural potholes. 

Findings

Based on the findings reported by the scientists, do 

you think prairie potholes provide valuable ecosystem 

services to people? Why or why not? Students should 

conclude that prairie potholes provide ecosystem 

services. These services include a higher variety of 

plants, help with addressing global climate change, 

protection from floods, and reduced soil erosion. 

Students will have to determine if they think these 

services are valuable. Students should support their 

determination with logic and sound reasons.

The scientists reported on four ecosystem services. 

Based on your reading of this article, what is one other 

ecosystem service provided by prairie potholes and 

pothole areas? Students should remember that potholes 

provide breeding habitat for waterfowl. If they do not 

remember this, urge them to reread “Thinking About 

the Environment.” Students may also be encouraged to 

imagine other ecosystem services that may be provided 

by prairie potholes. An example is habitat for other 

animal species.

Discussion

Based on the findings of this research, what is another 

research question the scientists could ask about prairie 

potholes and prairie pothole areas? (Hint: Reread the 

findings having to do with carbon and climate change.) 

The scientists did not expect to find that the soil of 

restored prairie potholes did not hold as much carbon as 

natural potholes. This finding suggests a number of new 

questions, such as: What is the relationship between the 

age of a restored pothole and the amount of carbon 

its soil holds? What might happen if the study was 

done 10 years from now when the restored potholes are 

older? Does the soil of restored natural land in other 

areas of the country also hold less carbon than similar 

natural areas? Your students may come up with other 

ideas about comparing the amount of carbon being 

held by natural and restored prairie potholes, or other 

types of land. They may come up with other questions 

as well. 

Do you agree that the CRP and the 

WRP have helped to provide ecosystem 

services? Why or why not? This is an 

individual question and students should 

back up their opinions with logic, 

evidence, and reason. 
64

Ecosystem Services Edition • http://www.naturalinquirer.org 

National Science Education Standards for 

Ecosystem Services Edition of the Natural Inquirer

Journal Article Toad-Ally Awesome! What Goes Around

Comes Around

Think Outside

the Box

Fill Those Potholes!

Science as Inquiry

Abilities Necessary To 

Do Scientific Inquiry

Understanding About 

Scientific Inquiry

Life Science

Structure & Function in 

Living Systems

Regulation & Behavior

Populations & Ecosystems

Diversity & Adaptations 

of Organisms

Earth Science

Structure of Earth System

Science in Personal &

Social Perspectives

Natural Hazards

Risks & Benefits

Science & Technology in 

Society

Science & Technology

Understanding About 

Science & Technology

History & Nature of

Science

Science as a Human 

Endeavor

Nature of Science
65

The Natural Inquirer • Volume 12 Number 1

The Forest Service is a part of 

the United States Department of 

Agriculture (USDA). It is made up of 

thousands of people who care for 

the Nation’s forest land. The Forest 

Service manages over 150 national forests and almost 

20 national grasslands. These are large areas of 

trees, streams, and grasslands. National forests are 

similar in some ways to national parks. Both are public 

lands, meaning that they are owned by the public 

and managed for the public’s use and benefit. Both 

national forests and national parks provide clean 

water, homes for the animals that live in the wild, and 

places for people to do fun things in the outdoors. 

National forests also provide resources for people to 

use, such as trees for lumber, minerals, and plants used 

for medicines. Some people in the Forest Service are 

scientists whose work is presented in the journal. Forest 

Service scientists work to solve problems and provide 

new information about natural resources so that we 

can make sure our natural environment is healthy, now 

and into the future. 

What is the

Forest Service?

What is the 

U.S. Geological Survey?

The U.S. Geological 

Survey, or USGS, is the 

Nation’s largest water, 

Earth, and biological 

science mapping agency. The USGS collects, keeps 

track of, evaluates, and provides scientific information 

about natural resource conditions, issues, and 

problems. The USGS has 10,000 scientists, technicians, 

and support staff working in more than 400 locations 

across the United States. People working with the 

USGS study the atmosphere, ecology, climate, Earth’s 

characteristics, ecology, geological processes, natural 

hazards, natural resources, oceans, coastlines, water, 

plants, and animals. They also produce maps and use 

maps to help further our understanding of everything 

on Earth. 

For additional information on ecosystem services,

visit these Web sites:

USDA Forest Service Ecosystem Services Web Site

http://www.fs.fed.us/ecosystemservices/

Climate Change Calculator

http://www.americanforests.org/resources/ccc/

Communicating Ecosystem Services

http://www.esa.org/ecoservices/

Ecosystem Services Fact Sheet

http://www.esa.org/ecoservices/comm/body.comm.

fact.ecos.html

Millennium Ecosystem Report

http://www.millenniumassessment.org/en/Index.aspx

National Biological Information Infrastructure

http://www.nbii.gov/portal/community/Communities/

NBII_Home/

The Globe Program

http://www.globe.gov/

The U.S. Department of Agriculture (USDA) prohibits 

discrimination in all its programs and activities on the basis 

of race, color, national origin, age, disability, and where 

applicable sex, marital status, familial status, parental 

status, religion, sexual orientation, genetic information, 

political beliefs, reprisal, or because all or part of and 

individuals’ income is derived from any public assistance 

program. (Not all prohibited bases apply to all programs.) 

Persons with disabilities who require alternative means for 

communication of program information (Braille, large print, 

audiotape, etc.) should contact USDA’s TARGET Center 

at (202) 720-2600 (voice and TDD). To file a complaint 

of discrimination, write to USDA, Director, Office of Civil 

Rights, 1400 Independence Avenue, S.W. 

Washington, D.C. 20250-9410, or call (800) 

795-3272 (voice) or (202) 720-6382 (TDD). 

USDA is an equal opportunity provider 

and employer.
FS-951