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Agroecology: The Ecology of Food Systems
C. Francis a , G. Lieblein b , S. Gliessman c , T. A. Breland b , N. Creamer d , R. Harwood d ,
L. Salomonsson e , J. Helenius f , D. Rickerl g , R. Salvador h , M. Wiedenhoeft j , S. Simmons
k , P. Allen e , M. Altieri l , C. Flora m & R. Poincelot n
a Department of Agronomy & Horticulture, University of Nebraska, Lincoln, NE
b Department of Horticulture & Crop Science, Agricultural University of Norway, Ås, Norway
c Department of Environmental Studies, University of California, Santa Cruz, CA
d CASFS, University of California, Santa Cruz, CA
e Department of Horticultural Science, University, Raleigh, NC
f Department of Crop & Soil Sciences, Michigan State University, East Lansing, MI
g Swedish University of Agricultural Sciences, Uppsala, Sweden
h Department of Plant Production, University of Helsinki, Helsinki, Finland
i Department of Plant Sciences, South Dakota State University, Brookings, SD
j Department of Agronomy, Iowa State University, Ames, IA
k Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN
l Division of Biological Control, University of California, Berkeley, CA.
m Department of Sociology, Iowa State University, Ames, IA
n Biology Department, Fairfield University, Fairfield, CT
Published online: 17 Oct 2008.
To cite this article: C. Francis , G. Lieblein , S. Gliessman , T. A. Breland , N. Creamer , R. Harwood , L. Salomonsson ,
J. Helenius , D. Rickerl , R. Salvador , M. Wiedenhoeft , S. Simmons , P. Allen , M. Altieri , C. Flora & R. Poincelot (2003)
Agroecology: The Ecology of Food Systems, Journal of Sustainable Agriculture, 22:3, 99-118, DOI: 10.1300/J064v22n03_10
To link to this article: http://dx.doi.org/10.1300/J064v22n03_10
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Agroecology:
The Ecology of Food Systems
C. Francis D. Rickerl
G. Lieblein R. Salvador
S. Gliessman M. Wiedenhoeft
T. A. Breland S. Simmons
N. Creamer P. Allen
R. Harwood M. Altieri
L. Salomonsson C. Flora
J. Helenius R. Poincelot
C. Francis is affiliated with the Department of Agronomy & Horticulture, Univer-
sity of Nebraska, Lincoln, NE.
G. Lieblein and T. A. Breland are affiliated with the Department of Horticulture &
Crop Science, Agricultural University of Norway, Ås, Norway.
S. Gliessman is affiliated with the Department of Environmental Studies, and P. Al-
len is affiliated with CASFS, University of California, Santa Cruz, CA.
N. Creamer is affiliated with the Department of Horticultural Science, North
Carolina State University, Raleigh, NC.
R. Harwood is affiliated with the Department of Crop & Soil Sciences, Michigan
State University, East Lansing, MI.
L. Salomonsson is affiliated with the Centre for Sustainable Agriculture, Swedish
University of Agricultural Sciences, Uppsala, Sweden.
J. Helenius is affiliated with the Department of Plant Production, University of Hel-
sinki, Helsinki, Finland.
D. Rickerl is affiliated with the Department of Plant Sciences, South Dakota State
University, Brookings, SD.
R. Salvador and M. Wiedenhoeft are affiliated with the Department of Agronomy,
and C. Flora is affiliated with the Department of Sociology, Iowa State University,
Ames, IA.
S. Simmons is affiliated with the Department of Agronomy and Plant Genetics,
University of Minnesota, St. Paul, MN.
M. Altieri is affiliated with the Division of Biological Control, University of Cali-
fornia, Berkeley, CA.
R. Poincelot is affiliated with the Biology Department, Fairfield University, Fairfield, CT.
Address correspondence to: C. Francis, Department of Agronomy & Horticulture,
University of Nebraska, Lincoln, NE 68583-0915 (E-mail: cfrancis2@unl.edu).
University of Nebraska Agricultural Research Division J. Serial No. 13535.
Journal of Sustainable Agriculture, Vol. 22(3) 2003
http://www.haworthpress.com/store/product.asp?sku=J064
2003 by The Haworth Press, Inc. All rights reserved.
10.1300/J064v22n03_10 99
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ABSTRACT. We present a compelling rationale for defining agroecol-
ogy as the ecology of food systems. Our purpose is to provide a frame-
work that will guide research, education, and action in the multiple and
interacting facets of an increasingly complex global agriculture and food
system. To accomplish such goals, it is essential to build bridges and
connections among and beyond our disciplines in production agricul-
ture, as well as beyond the farm gate into the rural landscape and com-
munity. Fields of sociology, anthropology, environmental sciences, ethics,
and economics are crucial to the mix. They provide additional vantage
points from which we can view the food system anew, as well as insights
on how to establish valuation criteria beyond neoclassical economics.
Examples from Mexico, California, and the Nordic Region are used to il-
lustrate the successful implementation of this educational strategy in
universities. Design of individual farms using principles of ecology is
expanded to the levels of landscape, community, and bioregion, with
emphasis on uniqueness of place and the people and other species that in-
habit that place. We conclude that defining agroecology as the ecology of
food systems will foster the development of broader interdisciplinary re-
search teams and attractive systems-based courses for tomorrow’s best
students. In contrast to the narrow focus on crop-soil interactions, this
definition will help us raise higher-level research questions whose solu-
tions will advance the development of a sustainable agriculture and food
system. [Article copies available for a fee from The Haworth Document Deliv-
ery Service: 1-800-HAWORTH. E-mail address: <docdelivery@haworthpress.
com> Website: <http://www.HaworthPress.com> 2003 by The Haworth Press,
Inc. All rights reserved.]
KEYWORDS. Agricultural systems, holistic research, action learning,
interdisciplinary studies
INTRODUCTION
We define agroecology as the integrative study of the ecology of the
entire food system, encompassing ecological, economic and social di-
mensions. This definition will lead to a practical approach that encour-
ages researcher, educator, and student to embrace the wholeness and
connectivity of systems, and will stimulate a focus on uniqueness of
each place, and solutions appropriate to its resources and constraints.
The definition expands our thinking beyond production practices and
immediate environmental impacts at the field and farm level.
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Agroecology has been variously defined as the ecology of agricul-
ture, the study of ecological functions in farming, and the marriage of
agriculture and ecology. More specifically, “Agroecology is defined as
the application of ecological concepts and principles to the design and
management of sustainable agroecosystems” (Gliessman, 1998). This
concept has captured the imaginations of farmers and academics who
are searching for innovative ways to increase productivity and sus-
tainability of agriculture while maintaining an environment that must
endure as well as provide quality of life. Short of dealing with the com-
plexity of improving today’s food systems, most research projects and
university courses–even in agroecology–focus on the narrow compo-
nents of agricultural production and their immediate environmental im-
pacts. Such focus does not reflect our expanding vision of how ecology
can inform the design and management of the total food system, nor
does it build on the ecological foundation that has been used in several
educational programs to support the development of sustainable agro-
ecosystems. Study of the ecology of food systems can provide insight
on how to deal with questions at the systems level and contribute to de-
velopment of sustainable societies.
Natural ecological systems have evolved over centuries to take effi-
cient advantage of natural resources. Interacting plant and animal spe-
cies survive well together in each given environment, including its
climate and soils. They provide a model of survival and relative stability
on which we can model modern agroecosystems. Natural systems are
essentially local, and they are most often biologically diverse. Clues
gleaned from natural systems can be blended with attentive human in-
novations to design future food systems.
Many instructive production practices are found in traditional agro-
ecosystems that represent a co-evolution of culture and nature. The
intricacies and potential value of indigenous systems were studied ex-
tensively by the Mexican ethnobotanist Efraim Hernandez X., who de-
fined agroecosystems as the interaction among ecological, technological,
and socio-economic factors. He explained why modern agricultural
systems have lost their ecological foundation, as socio-economic fac-
tors became the dominant driving forces in the food system (described
in Hernandez X., 1977). The maize/bean/squash system of Mexico and
Central America is an example of biological efficiency as well as con-
tribution to family diet.
In what ways can we recapture the knowledge developed over centu-
ries of traditional agricultural production experience, and link these
with the efficiencies of natural systems and with new technologies?
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Gliessman (1998) suggested that, “The greater the structural and func-
tional similarity of an agroecosystem to the natural ecosystems in its
biogeographic region, the greater the likelihood that the agroecosystem
will be sustainable.” One of our challenges in research is to discover
how the principles, the design, and the functions of natural systems can
be used as benchmarks or guides to development of productive, future
systems (Gliessman, 1990, 2001). The Land Institute in Kansas provides
one example of a research scenario based on the prairie as a model eco-
system (Jackson, 1980; Soule and Piper, 1992). Their national network
of 125 scientists is exploring how an understanding of natural systems
can be used to inform our search for productive future perennial-based
agroecosystems that operate in harmony with the environment and nat-
ural resources.
When we focus only on the production sector in agriculture, the anal-
ysis of current systems and design of future alternatives is severely con-
strained. Such focus ignores the large investment in energy and materials
that are integral to the processing, transportation, and marketing steps in
the food chain. In the industrial food system, it is a practical impossibil-
ity to reincorporate many of the waste products in this chain back into
the production cycle due to distance, cost, and logistical complications.
A global system may bring us bananas every day of the year, if we can
afford them, but it obscures the principal of seasonality in food produc-
tion in each place and the cycles that are both inherent and efficient in
natural systems. Building on principles of ecology and uniqueness of
place, agroecology and analysis of agroecosystems can provide meth-
ods for broadening the focus to analyzing all components of the food
system and how they interact.
PEOPLE IN AGROECOSYSTEMS
Our societies are open systems that result from human actions and
are based on demands, wishes, and vision. It is essential that we inte-
grate human behavior as an important driving force in the system. Our
current system separates most people from their sources of food and
from the production environment. In current urban culture, food may be
the only remaining connection to nature. This separation and lack of
awareness of how and where food is produced and processed contribute
to people’s decisions to consume fast food while discounting the impor-
tance of health as well as other human and environmental impacts (Nes-
tle, 2002; Schlosser, 2001). In addition, the global food system does not
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currently provide adequate food to the tables of the majority of people
on the planet. We must consider global equity in terms of nutrition,
health, and food security. A broader, interdisciplinary focus in agro-
ecology as the study of food systems will help us identify the real hu-
man costs and benefits of the current system and help account for what
are often considered externalities, both in the short and long terms.
These issues are already being addressed through the Common Agricul-
tural Policy (CAP) of the European Union, where emphasis is placed on
multifunctional landscapes including cultural values in each location.
With increasing global human population, there is growing aware-
ness of the need to increase food production while protecting bio-
diversity and the natural environment. Humans have the opportunity
and responsibility to evaluate food systems in new ways, to recognize
the need to balance the system with available resources, and to accept a
moral obligation to manage outputs from the system in an equitable
manner. When people are viewed as an integral part of the ecosystem,
subject to all the natural laws and consequences of system success, there
is a compelling reason to make agroecosystems as sustainable as possi-
ble for the long term. Beyond our current disruptive power in the eco-
system, we are capable of designing systems that close nutrient cycles,
depend more on renewable energy, reduce inefficiencies in production,
and promote environmental health. We can meet our goals by using
some system design principles and properties that resemble those of
natural ecosystems.
In this context, agroecology has appeal because it helps us focus on
structure and processes at each relevant systems level. Careful study
can lead to better analyses of the sustainability or potential negative
long-term environmental impacts of current agricultural practices and
systems. There are growing concerns by the public, often expressed
through regulations, that lead to requirements for agricultural practices
that will reduce the loss of soil and nutrients from fields and minimize
the entry of pesticides and their residues into surface and groundwater.
Learning more about the cycling processes and designs of natural sys-
tems can help us improve managed agroecosystems. Up to the present,
the focus in agricultural science has been primarily on components of
the production process, and maximizing net returns of single products
per unit of land or labor. All other resource use and environmental ef-
fects have been considered “externalities,” and have been excluded
from system design. The production focus is also reflected in design of
most current agroecology courses.
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The agricultural system is an open system, interacting with nature
and with society, and the development of a sustainable food system will
require more attention to the efficiency of the entire process of convert-
ing natural resources to what reaches consumers’ tables. This includes
analysis of food production, processing, marketing, and consumption.
When agroecology is defined as the ecology of food systems, we are ob-
ligated to look at more than the efficiencies of resource use in produc-
tion, the short-term environmental impacts of practices, and annual
enterprise economics. Most of the energy (perhaps >75%) in the food
system involves steps after the field production process (Johansson et
al., 2000). We need to consider the energy used and waste generated at
each step in the food chain, the potentials for cycling materials back into
primary production, and the emergent properties of a complex system
that is basic to human survival. We need to employ such tools as materi-
als life cycle analysis (Audsley et al., 1997), emergy analysis (Odum,
1996), environmental footprint calculations (Wackernagel et al., 1999),
and alternative economic and other valuation schemes (for review see
Doherty and Rydberg, 2002). Beyond looking at only the energy and
materials flows, we must consider other driving forces in the system
such as economics at the farm, national, and global levels, the environ-
mental consequences of systems on all plant and animal species, and the
social and health impacts of systems on people. An interdisciplinary, in-
tegrated approach is essential to adequately address the complexities of
interactions in the total food system (Allen et al., 1991).
EVOLUTION OF THE AGROECOLOGY CONCEPT
Gliessman (1998) traced the history of agroecology to the early part
of the past century when people in ecology and agronomy found com-
mon interests. The area of crop ecology included scientists exploring
where crops were grown and climatic conditions where each was best
adapted. Some proposed using the term agroecology. Both early and re-
cent publications using this term and related concepts are shown in Ta-
ble 1 (based on Gliessman, 1998).
These publications date back to the linking of the terms ecology and
agronomy in Klages’ 1928 article “Crop Ecology and Ecological Crop
Geography in the Agronomic Curriculum.” Gliessman describes how
groups of scientists diverged after World War II, with the ecologists
giving more focus to experiments in the natural environment and agron-
omists dedicating their attention to cultivated systems in agriculture.
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This separation of interests endured until the 1970s when books and ar-
ticles began to appear using the term agroecology and the concept of the
agroecosystem.
There were many indications from this new generation of authors
that agroecology would evolve to include more than the biogeochem-
ical environment and the crops grown there. Gliessman (1990) de-
scribed the pioneering work of Prof. Efraim Hernandez X. and his
students in Mexico who developed research based on indigenous sys-
tems and knowledge, and how this led to education programs in agro-
ecology (Hernandez X., 1977; Gliessman, 1978). In Agroecología del
Trópico Americano, Montaldo (1982) suggested that biological prob-
lems in designing agricultural practices are inseparable from the socio-
economic context in which agricultural systems are used.
In Sustainable Agriculture and Integrated Farming Systems (Edens
et al., 1985), there were sections devoted to economics of systems, eco-
logical impacts, and ethics and values in agriculture. These supple-
mented the expected papers on crop/animal integration, levels of input
use, and marketing alternatives that dominated the proceedings. Altieri
(1985) discussed pest management in the context of a changing struc-
ture of agriculture, including consolidation of farms, planting of mono-
cultures, and how these impact pest populations. Gliessman (1985)
added that “Socio-economic, technological, and ecological components
constantly interact, creating a complex feedback mechanism that through
time has selected for the types of food production systems that we ob-
serve today.” These agroecologists laid the foundation for what has be-
come in some programs a comprehensive study of the food system.
Parallel to this development was the emerging literature on agricultural
systems (e.g., Spedding, 1979, 1996).
The terms and concepts in Table 1 are limited to use of the term
agroecology, and only touch on the closely related publications and
strong growth in education and research in sustainable agriculture dur-
ing this same time frame. An overview of the modern historical devel-
opment of sustainable agriculture by Harwood (1990) described how an
evolving resource base, social values, and market structure were caus-
ing us to move from the current industrial model to something both
qualitatively and quantitatively different. This included a stable number
of people in production agriculture, a growing number in food services,
a shift from specialization toward enterprise integration, a change to-
ward more biological processes, and a quantum increase in social and
environmental considerations that influence public investment in the
food system.
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106 JOURNAL OF SUSTAINABLE AGRICULTURE
TABLE 1. Landmark publications using the term or the concept of agroecology
(modified from Gliessman, 1998; not all publications are cited in Reference
section).
Year Author(s) Title
1928 Klages Crop ecology and ecological crop geography in the
agronomic curriculum
1939 Hanson Ecology in agriculture
1956 Azzi Agricultural ecology
1965 Tischler Agrarökologie
1973 Janzen Tropical agroecosystems
1974 Harper The need for a focus on agro-ecosystems
1976 Loucks Emergence of research on agroecosystems
1977 Hernanez Xolocotzi Agroecosistemas de Mexico
1978 Gliessman Agroecosistemas y tecnologia agricola tradicional
1979 Hart Agroecosistemas: conceptos básicos
1979 Cox & Atkins Agricultural ecology: an analysis of world food production
systems
1980 Hart Agroecosistemas
1981 Gliessman, Garcia &
Amador
The ecological basis for the application of traditional
agricultural technology in the management of tropical
agroecosystems
1982 Montaldo Agroecologia del trópico americano
1983 Altieri Agroecology
1984 Lowrance, Stinner &
House
Agricultural ecosystems: unifying concepts
1985 Conway Agroecosystems analysis
1987 Altieri Agroecology: the scientific basis of alternative agriculture
1990 Allen, Dusen, Lundy,
& Gliessman
Integrating social, environmental, and economic issues in
sustainable agriculture
1990 Gliessman Agroecology: researching the ecological basis for
sustainable agriculture
1990 Carroll, Vandermeer
& Rosset
Agroecology
1990 Altieri & Hecht Agroecology and small farm development
1991 Caporali Ecologia per l'agricultura
1991 Bawden Systems thinking in agriculture
1993 Coscia Agricultura sostenible
1998 Gliessman Agroecology: ecological processes in sustainable
agriculture
2001 Flora Interactions between agroecosystems and rural
communities
2001 Gliessman Agroecosystem sustainability
2002 Dalgaard, Porter &
Hutchings
Agroecology, scaling, and interdisciplinarity
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Conway (1985) articulated the importance of basing agroecosystem
analysis on interdisciplinary study, using real farm cases in a workshop
setting. The process leads to “a set of agreed key questions for future re-
search or alternatively a set of tentative guidelines for development.”
Bawden (1991) pointed out that appropriate natural science approaches
such as farming systems research and agroecosystems analysis can be
enriched by social science methods that explore the cognitive issues in
farmer decision making.
There are close links to economics, to structure of agriculture, and to
ethical issues in food systems in the subsequent literature on sustainable
agriculture. For example, Coscia (1993) described the ethical or moral
obligation of each generation to preserve natural resources not used by
their ancestors and to provide at least the same opportunities for their
children and for succeeding generations. A practical series of field
guides for farmers and students began with Michigan Field Crop Ecol-
ogy (Cavigelli et al., 1998), a set that will soon include a volume on so-
cial/political linkages and the social contract. Interactions between
Agroecosystems and Rural Communities (Flora, 2001) illustrates the
rise in awareness of connections to the human community and human
capital. Integrative thinking is central to the current writings in sustain-
able agriculture, and those involved in teaching agroecology should be
aware of new research and education programs in this related arena.
The importance of interdisciplinary approaches and incorporation of
social systems methodology into research and education is summarized
by Dalgaard et al. (2002). In their paper, a compelling case is made for
broadening the application of ecological principles using a hierarchy of
scale to understand complexity in the production system. This approach
is similar to that used by Gliessman (1998). Agroecology is suggested
as the logical discipline to integrate across disciplines and different levels
of scale. Natural science methods can be used to describe the deci-
sion-support tools that will inform design of ecologically sound agricul-
ture, while social science methods can be used to integrate human
dimensions and help us better understand the total system.
TEXTS AND RESOURCE MATERIALS
The text Agroecologia del Trópico Americano (Montaldo, 1982) was
published by the Interamerican Institute for Agricultural Cooperation
(IICA) and made widely available through their offices throughout the
western hemisphere. Courses in Italy, especially in the University of
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Tuscia in Viterbo, have used the text by Fabio Caporali (1991), Ecologia
per L’Agricoltura: Teoria e Pratica, for the past decade. They primarily
deal with the production process and blending agriculture with ecology.
Writings of Miguel Altieri during the past two decades (e.g., Altieri,
1983, 1987; Altieri and Hecht, 1990) reflect a strong concern about the
equity issues in agriculture. In his research, teaching, and graduate ad-
vising, Altieri has integrated the social concerns of farm scale, agricul-
tural labor, and equity of benefits into the technical studies of IPM and
integrated farming systems. The text by Gliessman (1998) is probably
the most widely used in the U.S. at this time, and his edited reference
volume is widely cited in the literature (Gliessman, 1990). He has also
published a field and laboratory manual for teaching agroecology
(Gliessman, 2000). The book series edited by Clive Edwards and pub-
lished by CRC Press provides additional background and insight on
many dimensions of agroecology (for example, Buck et al., 1999; Col-
lins and Qualset, 1998; Flora, 2001; Gliessman, 2001).
COURSES AND CURRICULA IN AGROECOLOGY
Agroecology has its foundation in both ecology and in production
agriculture, as well as a number of other specific disciplines. Therefore
the development of educational programs depends in large part on the
components that are already well known and included in many courses
in the conventional curriculum. Agroecology, the ecology of food sys-
tems, provides a platform for the integration of numerous and complex
elements of the system with the objectives of understanding the struc-
tures and functions of systems, how to improve their design for more
sustainable, long-term production, and integrating goals for security
and equity in food for the future. Education must shift emphasis from
teaching how to maximize production of a single crop in a decontext-
ualized environment with unlimited access to fossil fuels, toward a food
systems level where the natural environment and society are recognized
in all their complexity. We find it increasingly important to link meth-
ods from natural and social sciences in designing education to meet
these goals.
Programs in Mexico: The importance of the ecological foundation of
agriculture has long been the emphasis of educational programs for sev-
eral undergraduate and graduate programs in Mexico. At the beginning
of the 1970s pioneering studies at the National School of Agriculture in
Chapingo (UACh) focused on the traditional agriculture of Mexican
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campesinos (peasant farmers). Graduate courses in ethnobotany devel-
oped the ideas that led to a national meeting “Agroecosistemas de Mex-
ico” in 1976 (Hernandez X., 1977), and a subsequent call for courses in
agronomic institutions country-wide that addressed the ecological, eco-
nomic, and social issues facing Mexican agroecosystems and farmers.
This approach was reviewed in a series of collected publications
(Hernandez X., 1985, 1987).
The Ecology Department of the Colegio Superior de Agricultura
Tropical (CSAT) in Tabasco offered courses in ecology, agroecology,
and tropical agroecosystems, emphasizing the values of traditional
agroecosystems (Gliessman, 1978). Classroom and laboratory learning
were applied through a semester of full-time residence in a local farm-
ing community, showing students how an agroecological approach
could link the ecology of food systems with the socioeconomic reality
being experienced by farmers. Agroecology in a cultural context was
provided by the Graduate Program in Anthropology at the Universidad
Iberoamericana in Mexico City (Gonzalez Jacome and Del Amo, 1999).
After an intensive short course in tropical agroecology in 1989 at the
Colegio de Postgraduados in Tabasco (the former CSAT) and an inter-
national symposium on agroecology in 1990 (Ferrera-Cerrato and
Quintero L., 1993), a Department of Agroecology was formed and a full
curriculum inaugurated in 1991. Emphasis is on ecologically-based
production processes and practices, with additional required courses in
economic, social, and cultural components of sustainable agriculture. In
ten years, 130 students have graduated and become the catalysts of
agroecology programs and curricula throughout Mexico.
Program at University of California Santa Cruz (UCSC): The first
course devoted specifically to Agroecology at UCSC was offered in
1981 as part of the Environmental Studies Program, and shortly thereaf-
ter the Agroecology Program (now Center for Agroecology and Sus-
tainable Food Systems) was initiated. A primary goal of the course has
been development and monitoring of indicators of agricultural sus-
tainability. A concern for incorporating economic and social dimen-
sions of agricultural production systems is reflected in the last chapter
of Agroecology, titled “From Sustainable Agriculture to Sustainable
Food Systems” (Gliessman, 1998). Students are encouraged to venture
beyond the conventional economic bottom line to consider impacts of
agriculture on the broader environment, the influence of agricultural
policy, and the complications of how short-term thinking and decisions
influence long-term system performance. Food system sustainability is
viewed as more than reduced pesticides and chemical fertilizers, but
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rather as involving equity of outputs and benefits and how alternative
systems affect diet and health.
The Agroecology and Sustainable Agriculture emphasis in Environ-
mental Studies at UCSC has expanded and flourished. Courses have
been added that promote ecologically-based methods of pest and dis-
ease control, as well as resource-conserving approaches to the design of
production systems. Other courses promote awareness and incorpora-
tion of the economic, social, and cultural aspects of agroecosystem
sustainability. Field internship experiences in agricultural communities
are offered as part of the program.
We speculate that introducing agroecology into agricultural curricula
is a large challenge to many conventional, discipline-oriented, reduc-
tionist scientists and educators. Agricultural specialists are more com-
fortable dealing with components of systems, simple cause-effect
relationships, and questions that can be answered by standard experi-
mental designs (Francis et al., 2001). Agroecology must involve inter-
disciplinary approaches, and these threaten the autonomy and budgets
of our disciplinary departments. It is intriguing to observe the develop-
ment of agroecology at UCSC in a non-landgrant, liberal arts univer-
sity.
Nordic Model for Agroecology: A broad definition of agroecology is
used to define courses in NOVA University (Francis et al., 2001;
Lieblein, 1997; Lieblein et al., 1999, 2000). The courses “challenge the
conventional metaphor of the food chain with its one-dimensional, linear
linking across the components. In contrast a local program emphasizes
the whole network of ecological (energetic and material), economic,
and socio-cultural (roles of actors, information, communication) link-
ages ‘vertically’ from production to processing, to markets, and to com-
munities consuming the goods, and their interdependence” (Francis et
al., 2001).
The NOVA regional working group in ecological agriculture spon-
sored a series of courses titled “From Farming Systems to Food Sys-
tems” (Lieblein, 1997) that centered learning on student activities in the
field, exploring and describing natural resources, production practices
and potentials, processing, marketing, and consumer concerns in the
Hedmark region of south-central Norway. A description of these modu-
lar courses is found in Lieblein et al. (1999). In these courses, we have
applied principles of action learning as summarized by Schubert (1995).
The NOVA working group is presently directing a regional research
and education project, “Improving the Nordic Region Education in
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Agroecology.” The goal is to develop an agroecological didactic for the
region (Lieblein and Østergaard, 2001).
The current NOVA University MSc program in agroecology is de-
signed as a two-year curriculum including a practical thesis project.
Study includes courses in Agroecology and Farming Systems and Agro-
ecology and Food Systems in Norway, and Adaptive Management in
Sweden. In general, these courses (1) establish their focus at a systems
level on farms and in the wider landscape, (2) look on systems in an in-
terdisciplinary way-integrating natural and social sciences, (3) handle
the system as open and interacting, and (4) use experiential learning as a
pedagogical base for understanding complex systems and action learn-
ing as the starting point in the field. Using ecological agriculture and
food systems as an alternative to the current system, they develop
visions for a future, sustainable food system and action plans for how to
get there. The courses use ecological agriculture as a case study ap-
proach because of its growing importance in Europe and elsewhere.
INTEGRATION INTO THE U.S. MAINSTREAM
Altieri and Francis (1992) explored how agroecology could be inte-
grated into the mainstream agricultural curriculum in our landgrant sys-
tem, urging educators to include topics linking production systems to
economic, cultural, and political systems, and to study how policy can
strongly influence practices and impacts of agriculture.
Today courses in agroecology are most often found in departments of
agronomy or biological sciences and emphasize ecology of production.
They focus on the ecology dimensions if taught by an ecologist, or on
production details if taught by an agronomist. They not only reflect the
backgrounds and disciplines of those doing the teaching, but also their
departments and the students who are attracted to the courses. Several
examples are listed in a compendium of educational materials (King
and Francis, 1994).
At University of Nebraska, Agroecology is a capstone course in the
Department of Agronomy and Horticulture. Its emphasis on the grass-
land ecosystem of the Great Plains features structure and function of the
prairie, climate and weather, and comparisons of natural and managed
ecosystems. Food processing and alternative local marketing systems
are compared to the global food system. Agricultural Ecology at Uni-
versity of Maine uses rapid rural appraisal within the broad social con-
text of systems. Use of indigenous ideas, biodiversity, pest management,
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and cover crops are specific topics, while industrialization, policy, and
human ethics and values make this one of the most diverse courses now
available.
Iowa State University (ISU), University of Minnesota, and Univer-
sity of Nebraska offer Agroecosystems Analysis as a summer travel
course that uses farm visits to provide a basis for analysis of production,
economics, environmental and landscape impacts, and social viability
of alternative practices and systems (Wiedenhoeft et al., 2002). ISU
also initiated new MS and PhD programs in sustainable agriculture in
Fall 2001. Agroecology is a new course at North Carolina State Univer-
sity that will be part of a proposed interdisciplinary minor. In the
eight-week residential course Experiential Learning in Sustainable Ag-
riculture, lectures are supplemented by hands-on experience in produc-
tion, marketing, extension, and research in the field. This course includes
a week that focuses on integrating societal dimensions of sustainable
agriculture.
These courses are heavily directed toward the ecological processes in
specific cropping patterns and the comparisons of conventional and al-
ternative agriculture. They include economic and ecological impacts of
systems as well as attention to the social impacts of systems on families.
In only one course is agricultural policy featured as a major topic in the
schedule. The courses illustrate current offerings in agroecology in U.S.
universities, and they include limited treatment of the complex steps of
processing, marketing, and consumption of food that lead to inefficien-
cies and costs of the global food chain. Likewise, there is uneven atten-
tion devoted to the multiple and complex issues of biological produc-
tion, economics at different levels of geographic scale, and driving
forces such as new biotechnologies, capital mobility and global mar-
kets, and eventual pressures due to inequities in distribution of benefits.
Defining agroecology as the ecology of food systems will help to
broaden the educational perspective in future courses.
CLOSING THE LOOP: EDUCATING THE CONSUMER
Agroecology needs to involve all parties, from scientist to producer
to processor to marketer to consumer, if the goal is to base our food sys-
tem on scientific foundations that can handle complexity and change.
Although much of the groundwork for programs has been laid, a direct
consumer involvement is most often missing. Only by closing such a
loop by including the consumer will the agroecological cycle be com-
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pleted. In particular, we need to get the attention of both urban and sub-
urban consumers. Those of us with experience teaching undergraduates
observe that students are under- or uninformed about the food system,
especially from an environmental and health perspective. This is equally
apparent with most community groups. Modern societies are organized
around fossil fuels as the driving force. As impacts of current systems
begin to threaten the life support base, interest will increase in less
dense, natural and contemporary energy resources. This will increase
public interest in rural areas and agricultural landscapes, and make the
message more palatable to urban audiences and students.
More consumers need to understand the connections among agricul-
ture, their food, their health, and their environment. To reach them we
need to emphasize the personal health and environmental benefits for
them and their families that are offered through better understanding of
the food system. Students and the general public do connect with health
issues such as benefits of fiber from vegetables and fruits, or relation-
ship between pesticides and cancer. Once informed, they are receptive
to information about local food systems including community gardens,
farm stands, compost, organic products and community supported agri-
culture, as well as more complex ecosystem functions and services such
as wetlands for clean water, windbreaks for clean air, intact soils that
don’t erode, and oxygen from green plants. Consumers will want to
learn more about their food supply and the rural landscape, and ulti-
mately will want information and choices from the system that an
agroecological approach can supply.
Organic food producers and processors have already been successful
in getting information to the public about the certified labels that iden-
tify their products in the market, as well as making direct connections
for sale from the farm. Just as commodity groups have promoted their
specific crop or animal product, organic growers and processors have
pursued public education campaigns using grower fees and contribu-
tions. One result is that growers benefit from the premium price that or-
ganic products will bring in the marketplace, thus increasing incomes
by advancing their labeled products. Organic food sales have increased
by about 20% per year for more than a decade in U.S. and Europe
(Lampkin, 1999).
Emphasis on consumer education should include explanations of
how ecological approaches used by sustainable farmers can produce
food without pesticides and with alternatives to chemical fertilizers,
while protecting the ecosystem and producing healthy, safe food for
consumers. The farmer can be portrayed as an environmental steward
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who is also concerned about consumer health, an ally of the consumer
who has made changes in farming practices to achieve these multiple
goals. Customers can be affirmed when they make the choices to pur-
chase food produced in this manner. Further education about how food
is produced, where, by whom, and under what conditions will reinforce
their decisions. Surveys in Norway have shown that consumers who
regularly purchase ecological food are also concerned about overall
pesticide and fertilizer use, about animal welfare, and about the condi-
tions of farmers and families where food is produced (Torjusen et al.,
2001). When agroecology studies the entire food system, these issues of
consumer opinion and choice are part of the equation.
CONCLUSIONS
We have defined agroecology as the study of the whole food system,
embracing both natural and social sciences, and emphasizing systems
thinking and ecological principles. Based on our collective experience
in teaching and research, we find it impossible to deal effectively with
the complexity of resource use and design of future systems if we only
focus on the production aspects, short-term economics, and environ-
mental impacts in the immediate vicinity of farm fields. It is logical to
suggest that agroecology should deal with all actors in food systems as
well as the total flow of energy and materials from their sources through
production and other steps to the consumer, and the potential to return
nutrients to the field. It is essential to carefully analyze the current
global food system and explore local alternatives, as well as unique op-
tions such as organic farming. Concepts in agroecology can be also be
applied to improving conventional farming systems.
Richard Harwood (personal communication, 2001) outlines the forces
that are shaping the dynamics of development and the emerging global
food situation in this new century. He lists the driving forces as new
technologies, mobility of capital and people, global markets, and an in-
frastructure increasingly dominated by multinational corporations. In
agriculture, some of the supplemental forces shaping the future include
collection and manipulation of germplasm, new information on genomics,
and dynamic breeding programs for our major staple crops. Corrective
forces are those invoked by governments and include global, regional,
and national policies as well as international oversight for trade, man-
agement of monopolies, and legislation that protects the environment.
Harwood lists sustaining forces as research in production ecology, ef-
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fective protection of natural resources, appropriate technologies and lo-
cal food systems, and strong action by the civil sector. Narrow focus on
specific technologies to increase food production or solve local envi-
ronmental problems can help some farmers, but will provide little
meaningful direction on how to design effective and sustainable sys-
tems for the future. A new definition of agroecology provides a ratio-
nale and brings intellectual resources to focus on some of the most
difficult and complex issues that challenge our ability to provide a sta-
ble food supply for the indefinite future.
Most educators involved in agroecology and sustainable agriculture
feel that a thoughtful analysis of the economic implications and long-
term impacts of alternative systems will help us sort out the complexi-
ties of resource use and environmental impacts that result from alterna-
tive agricultural and food processing systems. A broad evaluation of
productivity, economic return, environmental impact, and social equity
that quantifies the multiple consequences of alternative food systems
can help students and researchers ask the relevant questions, interpret
the results, and apply this information to design of productive and sus-
tainable agroecosystems. Moreover, it will be impossible to make sub-
stantial progress unless we also recognize the importance of literature,
philosophy, ethics, and other reflections of culture that help explain the
uniqueness of place, including people and resources. To introduce this
concept to a broader student audience, we urge continued dialog on both
the definition of agroecology and the development of innovative ap-
proaches to resource use and food systems for the future in our agricul-
tural colleges and universities world wide.
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RECEIVED: 09/27/01
REVISED: 06/10/02
ACCEPTED: 07/11/02
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