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SUSTAINABLE AGRICULTURE
Concept Themes
Farming and
Natural Resources
Plant
Production Practices
Animal
Production Practices
The Economic, Social
& Political Context
Agriculture has changed dramatically, especially
since the end of World War II. Food and fiber productivity soared due to new
technologies, mechanization, increased chemical use, specialization and
government policies that favored maximizing production. These changes allowed
fewer farmers with reduced labor demands to produce the majority of the food and
fiber in the U.S.
Although these changes have had many positive
effects and reduced many risks in farming, there have also been significant
costs. Prominent among these are topsoil depletion, groundwater contamination,
the decline of family farms, continued neglect of the living and working
conditions for farm laborers, increasing costs of production, and the
disintegration of economic and social conditions in rural communities.
A growing movement has emerged during the past
two decades to question the role of the agricultural establishment in promoting
practices that contribute to these social problems. Today this movement for
sustainable agriculture is garnering increasing support and acceptance within
mainstream agriculture. Not only does sustainable agriculture address many
environmental and social concerns, but it offers innovative and economically
viable opportunities for growers, laborers, consumers, policymakers and many
others in the entire food system.
This paper is an effort to identify the ideas,
practices and policies that constitute our concept of sustainable agriculture.
We do so for two reasons: 1) to clarify the research agenda and priorities of
our program, and 2) to suggest to others practical steps that may be appropriate
for them in moving toward sustainable agriculture. Because the concept of
sustainable agriculture is still evolving, we intend the paper not as a
definitive or final statement, but as an invitation to continue the dialogue.
Sustainable agriculture integrates three main
goals--environmental health, economic profitability, and social and economic
equity. A variety of philosophies, policies and practices have contributed to
these goals. People in many different capacities, from farmers to consumers,
have shared this vision and contributed to it. Despite the diversity of people
and perspectives, the following themes commonly weave through definitions of
sustainable agriculture.
Sustainability rests on the principle that we
must meet the needs of the present without compromising the ability of future
generations to meet their own needs. Therefore, stewardship of both natural
and human resources is of prime importance. Stewardship of human resources
includes consideration of social responsibilities such as working and living
conditions of laborers, the needs of rural communities, and consumer health and
safety both in the present and the future. Stewardship of land and natural
resources involves maintaining or enhancing this vital resource base for the
long term.
A systems perspective is essential to
understanding sustainability. The system is envisioned in its broadest sense,
from the individual farm, to the local ecosystem, and to communities
affected by this farming system both locally and globally. An emphasis on the
system allows a larger and more thorough view of the consequences of farming
practices on both human communities and the environment. A systems approach
gives us the tools to explore the interconnections between farming and other
aspects of our environment.
A systems approach also implies interdisciplinary
efforts in research and education. This requires not only the input of
researchers from various disciplines, but also farmers, farm workers, consumers,
policymakers and others.
Making the transition to sustainable
agriculture is a process. For farmers, the transition to sustainable
agriculture normally requires a series of small, realistic steps. Family
economics and personal goals influence how fast or how far participants can go
in the transition. It is important to realize that each small decision can make
a difference and contribute to advancing the entire system further on the
"sustainable agriculture continuum." The key to moving forward is the
will to take the next step.
Finally, it is important to point out that
reaching
toward the goal of sustainable agriculture is the responsibility of all
participants in the system, including farmers, laborers, policymakers,
researchers, retailers, and consumers. Each group has its own part to play, its
own unique contribution to make to strengthen the sustainable agriculture
community.
The remainder of this document considers specific
strategies for realizing these broad themes or goals. The strategies are grouped
according to three separate though related areas of concern: Farming and Natural
Resources, Plant and Animal Production Practices, and the Economic, Social and
Political Context. They represent a range of potential ideas for individuals
committed to interpreting the vision of sustainable agriculture within their own
circumstances.
Water. When the production of
food and fiber degrades the natural resource base, the ability of future
generations to produce and flourish decreases. The decline of ancient
civilizations in Mesopotamia, the Mediterranean region, Pre-Columbian southwest
U.S. and Central America is believed to have been strongly influenced by natural
resource degradation from non-sustainable farming and forestry practices. Water
is the principal resource that has helped agriculture and society to prosper,
and it has been a major limiting factor when mismanaged.
Water supply and use. In California, an
extensive water storage and transfer system has been established which has
allowed crop production to expand to very arid regions. In drought years,
limited surface water supplies have prompted overdraft of groundwater and
consequent intrusion of salt water, or permanent collapse of aquifers. Periodic
droughts, some lasting up to 50 years, have occurred in California. Several
steps should be taken to develop drought-resistant farming systems even in
"normal" years, including both policy and management actions: 1)
improving water conservation and storage measures, 2) providing incentives for
selection of drought-tolerant crop species, 3) using reduced-volume irrigation
systems, 4) managing crops to reduce water loss, or 5) not planting at all.
Water quality. The most important issues
related to water quality involve salinization and contamination of ground and
surface waters by pesticides, nitrates and selenium. Salinity has become a
problem wherever water of even relatively low salt content is used on shallow
soils in arid regions and/or where the water table is near the root zone of
crops. Tile drainage can remove the water and salts, but the disposal of the
salts and other contaminants may negatively affect the environment depending
upon where they are deposited. Temporary solutions include the use of
salt-tolerant crops, low-volume irrigation, and various management techniques to
minimize the effects of salts on crops. In the long-term, some farmland may need
to be removed from production or converted to other uses. Other uses include
conversion of row crop land to production of drought-tolerant forages, the
restoration of wildlife habitat or the use of agro-forestry to minimize the
impacts of salinity and high water tables. Pesticide and nitrate contamination
of water can be reduced using many of the practices discussed later in the Plant
Production Practices and Animal
Production Practices sections.
Wildlife. Another way in which
agriculture affects water resources is through the destruction of riparian
habitats within watersheds. The conversion of wild habitat to agricultural land
reduces fish and wildlife through erosion and sedimentation, the effects of
pesticides, removal of riparian plants, and the diversion of water. The plant
diversity in and around both riparian and agricultural areas should be
maintained in order to support a diversity of wildlife. This diversity will
enhance natural ecosystems and could aid in agricultural pest management.
Energy. Modern agriculture is
heavily dependent on non-renewable energy sources, especially petroleum. The
continued use of these energy sources cannot be sustained indefinitely, yet to
abruptly abandon our reliance on them would be economically catastrophic.
However, a sudden cutoff in energy supply would be equally disruptive. In
sustainable agricultural systems, there is reduced reliance on non-renewable
energy sources and a substitution of renewable sources or labor to the extent
that is economically feasible.
Air. Many agricultural
activities affect air quality. These include smoke from agricultural burning;
dust from tillage, traffic and harvest; pesticide drift from spraying; and
nitrous oxide emissions from the use of nitrogen fertilizer. Options to improve
air quality include incorporating crop residue into the soil, using appropriate
levels of tillage, and planting wind breaks, cover crops or strips of native
perennial grasses to reduce dust.
Soil. Soil erosion continues to
be a serious threat to our continued ability to produce adequate food. Numerous
practices have been developed to keep soil in place, which include reducing or
eliminating tillage, managing irrigation to reduce runoff, and keeping the soil
covered with plants or mulch. Enhancement of soil quality is discussed in the
next section.
Sustainable production practices involve a
variety of approaches. Specific strategies must take into account topography,
soil characteristics, climate, pests, local availability of inputs and the
individual grower's goals. Despite the site-specific and individual nature of
sustainable agriculture, several general principles can be applied to help
growers select appropriate management practices:
•
Selection of species and varieties that are
well suited to the site and to conditions on the farm;
•
Diversification of crops (including livestock)
and cultural practices to enhance the biological and economic stability of
the farm;
•
Management of the soil to enhance and protect
soil quality;
•
Efficient and humane use of inputs; and
•
Consideration of farmers' goals and lifestyle
choices.
Selection of site, species and variety.
Preventive strategies, adopted early, can reduce inputs and help establish a
sustainable production system. When possible, pest-resistant crops should be
selected which are tolerant of existing soil or site conditions. When site
selection is an option, factors such as soil type and depth, previous crop
history, and location (e.g. climate, topography) should be taken into account
before planting.
Diversity. Diversified farms are
usually more economically and ecologically resilient. While monoculture farming
has advantages in terms of efficiency and ease of management, the loss of the
crop in any one year could put a farm out of business and/or seriously disrupt
the stability of a community dependent on that crop. By growing a variety of
crops, farmers spread economic risk and are less susceptible to the radical
price fluctuations associated with changes in supply and demand.
Properly managed, diversity can also buffer
a farm in a biological sense. For example, in annual cropping systems, crop
rotation can be used to suppress weeds, pathogens and insect pests. Also, cover
crops can have stabilizing effects on the agroecosystem by holding soil and
nutrients in place, conserving soil moisture with mowed or standing dead
mulches, and by increasing the water infiltration rate and soil water holding
capacity. Cover crops in orchards and vineyards can buffer the system against
pest infestations by increasing beneficial arthropod populations and can
therefore reduce the need for chemical inputs. Using a variety of cover crops is
also important in order to protect against the failure of a particular species
to grow and to attract and sustain a wide range of beneficial arthropods.
Optimum diversity may be obtained by integrating
both crops and livestock in the same farming operation. This was the common
practice for centuries until the mid-1900s when technology, government policy
and economics compelled farms to become more specialized. Mixed crop and
livestock operations have several advantages. First, growing row crops only on
more level land and pasture or forages on steeper slopes will reduce soil
erosion. Second, pasture and forage crops in rotation enhance soil quality and
reduce erosion; livestock manure, in turn, contributes to soil fertility. Third,
livestock can buffer the negative impacts of low rainfall periods by consuming
crop residue that in "plant only" systems would have been considered
crop failures. Finally, feeding and marketing are flexible in animal production
systems. This can help cushion farmers against trade and price fluctuations and,
in conjunction with cropping operations, make more efficient use of farm labor.
Soil management. A common
philosophy among sustainable agriculture practitioners is that a
"healthy" soil is a key component of sustainability; that is, a
healthy soil will produce healthy crop plants that have optimum vigor and are
less susceptible to pests. While many crops have key pests that attack even the
healthiest of plants, proper soil, water and nutrient management can help
prevent some pest problems brought on by crop stress or nutrient imbalance.
Furthermore, crop management systems that impair soil quality often result in
greater inputs of water, nutrients, pesticides, and/or energy for tillage to
maintain yields.
In sustainable systems, the soil is viewed as a
fragile and living medium that must be protected and nurtured to ensure its
long-term productivity and stability. Methods to protect and enhance the
productivity of the soil include using cover crops, compost and/or manures,
reducing tillage, avoiding traffic on wet soils, and maintaining soil cover with
plants and/or mulches. Conditions in most California soils (warm, irrigated, and
tilled) do not favor the buildup of organic matter. Regular additions of organic
matter or the use of cover crops can increase soil aggregate stability, soil
tilth, and diversity of soil microbial life.
Efficient use of inputs. Many
inputs and practices used by conventional farmers are also used in sustainable
agriculture. Sustainable farmers, however, maximize reliance on natural,
renewable, and on-farm inputs. Equally important are the environmental, social,
and economic impacts of a particular strategy. Converting to sustainable
practices does not mean simple input substitution. Frequently, it substitutes
enhanced management and scientific knowledge for conventional inputs, especially
chemical inputs that harm the environment on farms and in rural communities. The
goal is to develop efficient, biological systems which do not need high levels
of material inputs.
Growers frequently ask if synthetic chemicals are
appropriate in a sustainable farming system. Sustainable approaches are those
that are the least toxic and least energy intensive, and yet maintain
productivity and profitability. Preventive strategies and other alternatives
should be employed before using chemical inputs from any source. However, there
may be situations where the use of synthetic chemicals would be more
"sustainable" than a strictly non-chemical approach or an approach
using toxic "organic" chemicals. For example, one grape grower
switched from tillage to a few applications of a broad spectrum contact
herbicide in the vine row. This approach may use less energy and may compact the
soil less than numerous passes with a cultivator or mower.
Consideration of farmer goals and
lifestyle choices. Management decisions should reflect not only
environmental and broad social considerations, but also individual goals and
lifestyle choices. For example, adoption of some technologies or practices that
promise profitability may also require such intensive management that one's
lifestyle actually deteriorates. Management decisions that promote
sustainability, nourish the environment, the community and the
individual.
In the early part of this century, most farms
integrated both crop and livestock operations. Indeed, the two were highly
complementary both biologically and economically. The current picture has
changed quite drastically since then. Crop and animal producers now are still
dependent on one another to some degree, but the integration now most commonly
takes place at a higher level--between farmers, through intermediaries,
rather than within the farm itself. This is the result of a trend
toward separation and specialization of crop and animal production systems.
Despite this trend, there are still many farmers, particularly in the Midwest
and Northeastern U.S. that integrate crop and animal systems--either on dairy
farms, or with range cattle, sheep or hog operations.
Even with the growing specialization of livestock
and crop producers, many of the principles outlined in the crop production
section apply to both groups. The actual management practices will, of course,
be quite different. Some of the specific points that livestock producers need to
address are listed below.
Management Planning. Including
livestock in the farming system increases the complexity of biological and
economic relationships. The mobility of the stock, daily feeding, health
concerns, breeding operations, seasonal feed and forage sources, and complex
marketing are sources of this complexity. Therefore, a successful ranch plan
should include enterprise calendars of operations, stock flows, forage flows,
labor needs, herd production records and land use plans to give the manager
control and a means of monitoring progress toward goals.
Animal Selection.
The animal
enterprise must be appropriate for the farm or ranch resources. Farm
capabilities and constraints such as feed and forage sources, landscape, climate
and skill of the manager must be considered in selecting which animals to
produce. For example, ruminant animals can be raised on a variety of feed
sources including range and pasture, cultivated forage, cover crops, shrubs,
weeds, and crop residues. There is a wide range of breeds available in each of
the major ruminant species, i.e., cattle, sheep and goats. Hardier breeds that,
in general, have lower growth and milk production potential, are better adapted
to less favorable environments with sparse or highly seasonal forage growth.
Animal nutrition.
Feed costs are
the largest single variable cost in any livestock operation. While most of the
feed may come from other enterprises on the ranch, some purchased feed is
usually imported from off the farm. Feed costs can be kept to a minimum by
monitoring animal condition and performance and understanding seasonal
variations in feed and forage quality on the farm. Determining the optimal use
of farm-generated by-products is an important challenge of diversified farming.
Reproduction. Use of quality
germplasm to improve herd performance is another key to sustainability. In
combination with good genetic stock, adapting the reproduction season to fit the
climate and sources of feed and forage reduce health problems and feed costs.
Herd Health.
Animal health
greatly influences reproductive success and weight gains, two key aspects of
successful livestock production. Unhealthy stock waste feed and require
additional labor. A herd health program is critical to sustainable livestock
production.
Grazing Management. Most adverse
environmental impacts associated with grazing can be prevented or mitigated with
proper grazing management. First, the number of stock per unit area (stocking
rate) must be correct for the landscape and the forage sources. There will need
to be compromises between the convenience of tilling large, unfenced fields and
the fencing needs of livestock operations. Use of modern, temporary fencing may
provide one practical solution to this dilemma. Second, the long term carrying
capacity and the stocking rate must take into account short and long-term
droughts. Especially in Mediterranean climates such as in California, properly
managed grazing significantly reduces fire hazards by reducing fuel build-up in
grasslands and brush lands. Finally, the manager must achieve sufficient control
to reduce overuse in some areas while other areas go unused. Prolonged
concentration of stock that results in permanent loss of vegetative cover on
uplands or in riparian zones should be avoided. However, small scale loss of
vegetative cover around water or feed troughs may be tolerated if surrounding
vegetative cover is adequate.
Confined Livestock Production.
Animal health and waste management are key issues in confined livestock
operations. The moral and ethical debate taking place today regarding animal
welfare is particularly intense for confined livestock production systems. The
issues raised in this debate need to be addressed.
Confinement livestock production is increasingly
a source of surface and ground water pollutants, particularly where there are
large numbers of animals per unit area. Expensive waste management facilities
are now a necessary cost of confined production systems. Waste is a problem of
almost all operations and must be managed with respect to both the environment
and the quality of life in nearby communities. Livestock production systems that
disperse stock in pastures so the wastes are not concentrated and do not
overwhelm natural nutrient cycling processes have become a subject of renewed
interest.
In addition to strategies for preserving natural
resources and changing production practices, sustainable agriculture requires a
commitment to changing public policies, economic institutions, and social
values. Strategies for change must take into account the complex, reciprocal and
ever-changing relationship between agricultural production and the broader
society.
The "food system" extends far beyond
the farm and involves the interaction of individuals and institutions with
contrasting and often competing goals including farmers, researchers, input
suppliers, farm workers, unions, farm advisors, processors, retailers, consumers,
and policymakers. Relationships among these actors shift over time as new
technologies spawn economic, social and political changes.
A wide diversity of strategies and approaches are
necessary to create a more sustainable food system. These will range from
specific and concentrated efforts to alter specific policies or practices, to
the longer-term tasks of reforming key institutions, rethinking economic
priorities, and challenging widely-held social values. Areas of concern where
change is most needed include the following:
Food and agricultural policy.
Existing federal, state and local government policies often impede the goals of
sustainable agriculture. New policies are needed to simultaneously promote
environmental health, economic profitability, and social and economic equity.
For example, commodity and price support programs could be restructured to allow
farmers to realize the full benefits of the productivity gains made possible
through alternative practices. Tax and credit policies could be modified to
encourage a diverse and decentralized system of family farms rather than
corporate concentration and absentee ownership. Government and land grant
university research policies could be modified to emphasize the development of
sustainable alternatives. Marketing orders and cosmetic standards could be
amended to encourage reduced pesticide use. Coalitions must be created to
address these policy concerns at the local, regional, and national level.
Land use. Conversion of
agricultural land to urban uses is a particular concern in California, as rapid
growth and escalating land values threaten farming on prime soils. Existing
farmland conversion patterns often discourage farmers from adopting sustainable
practices and a long-term perspective on the value of land. At the same time,
the close proximity of newly developed residential areas to farms is increasing
the public demand for environmentally safe farming practices. Comprehensive new
policies to protect prime soils and regulate development are needed,
particularly in California's Central Valley. By helping farmers to adopt
practices that reduce chemical use and conserve scarce resources, sustainable
agriculture research and education can play a key role in building public
support for agricultural land preservation. Educating land use planners and
decision-makers about sustainable agriculture is an important priority.
Labor.
In California, the
conditions of agricultural labor are generally far below accepted social
standards and legal protections in other forms of employment. Policies and
programs are needed to address this problem, working toward socially just and
safe employment that provides adequate wages, working conditions, health
benefits, and chances for economic stability. The needs of migrant labor for
year-around employment and adequate housing are a particularly crucial problem
needing immediate attention. To be more sustainable over the long-term, labor
must be acknowledged and supported by government policies, recognized as
important constituents of land grant universities, and carefully considered when
assessing the impacts of new technologies and practices.
Rural Community Development.
Rural communities in California are currently characterized by economic and
environmental deterioration. Many are among the poorest locations in the nation.
The reasons for the decline are complex, but changes in farm structure have
played a significant role. Sustainable agriculture presents an opportunity to
rethink the importance of family farms and rural communities. Economic
development policies are needed that encourage more diversified agricultural
production on family farms as a foundation for healthy economies in rural
communities. In combination with other strategies, sustainable agriculture
practices and policies can help foster community institutions that meet
employment, educational, health, cultural and spiritual needs.
Consumers and the Food System.
Consumers can play a critical role in creating a sustainable food system.
Through their purchases, they send strong messages to producers, retailers and
others in the system about what they think is important. Food cost and
nutritional quality have always influenced consumer choices. The challenge now
is to find strategies that broaden consumer perspectives, so that environmental
quality, resource use, and social equity issues are also considered in shopping
decisions. At the same time, new policies and institutions must be created to
enable producers using sustainable practices to market their goods to a wider
public. Coalitions organized around improving the food system are one specific
method of creating a dialogue among consumers, retailers, producers and others.
These coalitions or other public forums can be important vehicles for clarifying
issues, suggesting new policies, increasing mutual trust, and encouraging a
long-term view of food production, distribution and consumption.
FOR MORE INFORMATION:
Contact
the UC Sustainable Agriculture Research and Education Program, University of
California, Davis, CA 95616, (916) 752-7556. Written by Gail
Feenstra, Writer; Chuck Ingels, Perennial Cropping Systems Analyst;
and David Campbell, Economic and Public Policy Analyst with contributions from David
Chaney, Melvin R. George, Eric Bradford, the staff and advisory
committees of the UC Sustainable Agriculture Research and Education Program.
University of California -
Sustainable Agriculture - Research and Education Program CLICK
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