ERIC Identifier: ED478712
Publication Date: 2002-07-00
Author: Haury, David L.
Source: ERIC Clearinghouse for
Science Mathematics and Environmental Education Columbus OH.
Teaching about Ecosystems. ERIC Digest.
When someone asks us where we are from or what we do, most of us mention the
town or city where we live, our occupation, where we attended school, or our
family heritage. We respond in terms of human communities, cultures, and
geopolitical boundaries. We seldom, if ever, describe ourselves in terms of our
ecological status in the natural world. We humans have so completely ordered,
designed, and defined our physical environs and social milieu that our
ecological connections have slipped from consciousness. Perhaps this is why we
seem so unaware of our impact on nature and our rapid destruction of natural
systems. We simply do not perceive ourselves as being part of the natural order
All of us live within ecological systems, or "ecosystems", and through our
commerce, food distribution, and use of natural resources we each indirectly
participate in the custodianship of many ecosystems worldwide. Ironically, we
are simultaneously the most potent forces within most ecosystems, and yet nearly
oblivious to the ecological effects of our daily lifestyles. There has never
been a time when a deep understanding of ecosystems and our roles within them
has been more critical. Indeed, the world's freshwater ecosystems are so
degraded that their ability to support plant and animal life, including humans,
is viewed by many as being in peril (Revenga, Brunner, Henninger, Kassem, &
Payne, 2000). Learning about ecosystems is more than an expected focus in
biology classes; it has become a study in survival.
Ecosystems are functional units of interacting abiotic, biotic, and cultural
(anthropogenic) components. All natural ecosystems are open systems where energy
and matter are transferred in and out through the complex interactions of
energy, water, carbon, oxygen, nitrogen, phosphorus, sulfur, and other cycles.
Unfortunately, many scientists contend, we humans have disrupted the balance of
transfers across ecosystem boundaries. In addition to learning our place within
ecosystems, we must learn to become better stewards and managers of ecosystems.
A history of the ecosystem concept has been presented by Bocking (1994).
Unfortunately, some concepts related to ecosystems--food web, ecological
adaptation, carrying capacity, niche--are complex and lead to misconceptions
among students (Munson, 1994).
ECOSYSTEMS IN THE CURRICULUM
considerable attention in national curriculum standards and guidelines. Both the "National Science Education Standards" (NSES, National Research Council, 1996)
and the "Excellence in Environmental Education: Guidelines for Learning (K-12)"
(EEE, North American Association for Environmental Education, 2000) use systems
as an organizing concept. Within the "Standards", the "unifying concepts and
processes" for K-12 content standards include "Systems, Order, and
Organization", and within the EEE "Guidelines", one of the four organizing
strands is "Knowledge of Environmental Processes and Systems" that includes
specific guidelines regarding ecosystems and their components. The "Standards"
also include several content standards pertaining to ecosystems in the Life
Science strand and the "Science in Personal and Social Perspectives" strand.
Following is a overview of the standards and guidelines specifically relating to
and Guidelines for Grades 5-8
Content Standards (NSES)
* The complementary nature of structure and function within ecosystems.
* All populations living together and the physical factors with which they
interact compose an ecosystem.
* Populations of organisms can be categorized by the function they serve in
an ecosystem, and food webs identify the relationships among producers,
consumers, and decomposers in an ecosystem.
* Energy entering ecosystems as sunlight is transferred by producers into
chemical energy through photosynthesis. That energy then passes from organism to
organism in food webs.
* The number of organisms an ecosystem can support depends on the resources
available and abiotic factors.
Living Environment Guidelines" (EEE)
* Define ecosystem and give examples of connections among organisms at this
level of organization.
* Summarize how abiotic and biotic components in combination influence the
structure of an ecosystem.
* Describe how energy, which enters ecosystems as sunlight, changes form and
is transferred in the exchanges (production, consumption, and decomposition)
that comprise food webs.
and Guidelines for Grades 9-12
"Content Standards" (NSES)
* Energy flows through ecosystems in one direction, from photosynthetic
organisms to herbivores to carnivores and decomposers.
* Organisms both cooperate and compete in ecosystems. The interrelationships
and interdependencies of these organisms may generate ecosystems that are stable
for hundreds or thousands of years.
* Human beings live within the world's ecosystems. Increasingly, humans
modify ecosystems as a result of population growth, technology, and consumption.
Human destruction of habitats through direct harvesting, pollution, atmospheric
changes, and other factors is threatening current global stability, and if not
addressed, ecosystems will be irreversibly affected.
* The distribution and abundance of organisms and populations in ecosystems
are limited by the availability of matter and energy and the ability of the
ecosystem to recycle materials
* Natural ecosystems provide an array of basic processes that affect humans.
Those processes include maintenance of the quality of the atmosphere, generation
of soils, control of the hydrologic cycle, disposal of wastes, and recycling of
nutrients. Humans are changing many of these basic processes, and the changes
may be detrimental to humans.
"The Living Environment Guidelines" (EEE)
* Apply the concepts of ecosystem and ecoregion to organize the multitude of
relationships among organisms and environments.
* Explain ecosystem change with respect to variables such as climate change,
the introduction of new species, and human impacts; and explain processes such
as desertification and soil formation as mechanisms for such change.
* Describe succession in ecosystems and their constituent plant and animal
* Describe how adding a species to, or removing one from, an ecosystem may
affect other organisms and the entire system.
There are many additional standards and guidelines that directly or
indirectly relate to ecosystems, but this overview provides the basic conceptual
framework to be developed through the school curriculum. It should be noted that
the framework includes attention both to basic concepts pertaining to ecological
systems as well as the impacts of human activity on ecosystem change and
BEYOND THE TEXTBOOK AND STANDARDS
As Noss, LaRoe, and Scott
(1995) have so convincingly documented, there have been severe declines in the
area and natural quality of terrestrial and aquatic ecosystems in all regions of
the United States. Habitat loss, ecosystem degradation, and ecosystem
fragmentation have led to great losses in biodiversity. Indeed, entire
ecosystems are endangered along with individual species. Though management
efforts have led to the gradual recovery of some ecosystems, there is a need for
citizens to gain a greater sense of their ecological connections and the
long-term impacts of human activities.
Schools and individual teachers are responding by developing programs and
learning experiences that focus on ecosystems, field study, and examinations of
human impact through actions and decisions. Tracy and Glaser (1999) described an
immersion program in which K-5 students meet all curriculum guidelines through
investigating, monitoring, and restoring schoolground habitats and local
ecosystems. Lewis (1999) focuses on an analysis of human impacts through
ecosystem surveys that engage students in formulating and testing hypotheses
about human impacts.
Freeman (2002) describes a unique approach to studying the human impact on
ecosystems through ongoing study of an artificial aquatic ecosystem by students
in grades 7 through 12. She describes activities that are woven into the
curriculum of integrated science, biology, chemistry, and physics over a six
Another curriculum approach that combines study of ecosystems with
consideration of human impacts and decision making is offered by the Forest
Service Employees for Environmental Ethics (2000). Their Secret Forest
Experience Curriculum is designed for middle school students and engages
students in five science-based projects related to ecosystems of western U. S.
forests. The materials are available in both English and Spanish.
Finally, Brodie (1995) offers background and activities related to a unique
ecosystem, the Great Basin of the western United States, that draws attention to
web of life within deserts. This unit of study is appropriate for upper
elementary and middle school students, and includes both a historical
perspective and visions of future options in terms of human impact on this arid
REACHING BEYOND THE SCIENCE CLASSROOM
To supplement the
traditional content on ecosystems in science classes, some groups have developed
instructional materials and activities that integrate ecosystem concepts with a
range of topics and subjects. Following are selected examples of materials that
are available to teachers.
Adams, M., Brickell, R., & Hanophy, W. (Senior Eds.). (1995). "Ecosystem
matters: Activity and resource guide for environmental educators". Washington,
DC: U. S. Department of Agriculture. [ED 403 116]
This compendium of activities is intended for classroom teachers, nature camp
instructors, scout leaders, forest rangers, naturalists, and others who are
helping learners make conscious decision that lead to the long-term stewardship
of natural resources. This guide was designed to supplement existing courses and
programs concerning ecological matters, and the activities focus on ecosystem
management. The interdisciplinary activities relate to topics in social studies,
drama, language arts, geography, history, math, physical education, and science,
and the activities are categorized by grades K-3 (13 activities), grades 4-5 (20
activities), grades 6-8 (25 activities), and grades 9-12 (13 activities.
Lewis, J. (1999). "People, growth, and endangered ecosystems: Exercises in
biodiversity, grades 6-12". Tallahassee: Florida State Department of
Environmental Protection. [ED 434 013]
This document features interdisciplinary activities that combine the study of
biology with music, art, language arts and social studies. The activities are
aimed at students in middle school through the first two years of high school.
All activities can be conducted in the classroom or outdoors near the school.
SELECTED WORLD WIDE WEB RESOURCES
"Living Things: Habitats
and Ecosystems" A resource of the Franklin Institute
"Earth on Edge: Ecosystems" A Web resource associated with Bill Moyers
Reports on PBS that examines the status of the world's ecosystems
"Exploring Ecosystems Online" An electronic field trip for grades 7-12
provided by the Smithsonian Institution's National Museum of Natural History
"Ecosystems of Our World" An interactive Think Quest resource featuring ten
different ecosystems http://library.thinkquest.org/11353/ecosystems.htm
"Freshwater Ecosystems" An extensive directory of Web resources and lesson
plans on aquatic ecosystems in Canada and the United States
"Ecosystems" A Learning Web resource provided by the U.S. Geological Survey
"Backyard Science: How Ecosystems Work" Online teaching guide for an activity
suitable for students in grades 5-12.
"Ecosystems" A lesson plan from Discovery.com suitable for students in grades
FINDING INFORMATION IN THE ERIC DATABASE
There are many
records in the ERIC Database pertaining to ecosystems, but it takes a little
searching to find them. The term ecosystem is not used to index records in ERIC,
so it is best to search using "ecology" as a Descriptor, combined with ecosystem
or ecosystems as keywords. You can narrow your search by combining these terms
with one or more of the following Descriptors: "teaching methods",
"instructional materials", "experiential learning", "hands on science",
"environmental education", or similar terms. You can further narrow your search
by using education level Descriptors, such as "elementary education", "middle
schools", "intermediate grades", or "junior high schools", or individual grade
levels. You can search the database on the Web at
Bocking, S. (1994, July-August). Visions of
nature and society: A history of the ecosystem concept. "Alternatives", 20 (3),
12-18. [EJ 491 835]
Brodie, J. M. (1995, May). The big empty. "Science & Children". Also
available online at: http://www.blm.gov/education/great_basin/great_basin.html
Forest Service Employees for Environmental Ethics. (2000). "The secret forest
experience". Eugene, OR: Author. Available online at:
Freeman, C. C. (2002). "Building an ecosystem. Access Excellence, Activities
Exchange", The National Health Museum,
Lewis, J. K. (1999). "Surveying an ecosystem: An exercise for high school
biology students". Tallahassee, FL: Florida State Department of Environmental
Munson, B.H. (1994, Summer). Ecological misconceptions. "Journal of
Environmental Education", 25 (4), 30-34.
National Research Council. (1996). "National science education standards".
Washington, DC: National Academy Press. (Available online at:
North American Association for Environmental Education. (2000). "Excellence
in environmental education: Guidelines for learning (K-12)". Washington, DC:
Noss, R. F., LaRoe, E. T., & Scott, J. M. (1995). "Endangered ecosystems
of the United States: A preliminary assessment of loss and degradation".
Biological Report 28. Washington, DC: USDI National Biological Service.
(Available online at: http://biology.usgs.gov/pubs/ecosys.htm)
Revenga, C., Brunner, J., Henninger, N., Kassem, K., & Payne, R. (2000).
"Pilot analysis of global ecosystems: Freshwater systems". Washington, DC: World
Recources Institute. (Available online at:
Tracy, J., & Glaser, K. (1999, Fall). Ecology project learning. "Green
Teacher", no. 59, 5-9.