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The phrase "sustainable development" was popularized
during the 1980's by the United Nations' World Commission
on Environment and Development, which defined it as “development
that meets the needs of the present without compromising
the ability of future generations to meet their own needs.”
Contents
Agriculture's Role
in Sustainable Development
Sustainability recognizes that economic well-being transcends
the traditional view of economic goods and services (like
food and clothing) to include goods and services not necessarily
purchased in markets, such as recreation, safe drinking
water, and scenery. Sustainability requires investing
in an appropriate mix of human made capital (e.g., buildings
and machinery) and natural capital (e.g. farmland, aquifers,
lakes, rivers, estuaries, and wetlands) to maximize current
and future economic well-being.
Agriculture has a unique role in sustainability. It produces
food and relies on natural capital for production. Agriculture
also accounts for a majority of land and water use and
is a major contributor to impairment of rivers, lakes,
and estuaries. Because both food and natural capital are
necessary for future generations, a more sustainable path
of economic development requires effective stewardship
in agricultural production. This view is consistent with
the USDA Secretary's Memorandum on Sustainable Development:
“USDA will balance goals of improved production
and profitability, stewardship of the natural resource
base and ecological system, and enhancement of the vitality
of rural communities.”
Additional information is available on agriculture's
role in sustainability from the Sustainable
Agriculture Network and from the CSREES.
Indicators of Agricultural
Sustainability and the Contribution of Technology to Agricultural
Sustainability
Indicators of agricultural sustainability pertain both
to the ability to provide food to current and future generations
at reasonable costs (agricultural productivity,
soil erosion, and groundwater
quantity) and to environmental impacts associated
with agricultural production (surface-water
quality, groundwater quality,
and wetland conversion rates).
Agricultural productivity measures the difference
between output growth and input growth rates. If productivity
growth is positive, then the same output can be produced
with fewer inputs and lower costs. Over 1948-94, output
in U.S. agriculture grew at an annual average rate of
1.9 percent, compared with 1.1 percent for the nonfarm
sector. Greater agricultural
productivity growth, higher yields, and lower farm
prices have benefited consumers by supplying food at a
reasonable cost. By 1996, the share of disposable personal
income spent on food had fallen to 11 percent, compared
with 22 percent in 1948.
Soil erosion has declined by an estimated
40 percent since 1938, while cropland use has remained
remarkably stable at about 400 million acres. Most of
the erosion decline has occurred since 1982, when total
erosion from cropland was estimated at 3.1 billion tons
per year, or 7.4 tons per acre per year. By 1992, total
erosion from cropland declined to 2.1 billion tons, or
5.6 tons per acre. The post-1982 decline results from
government programs aimed at mitigating the environmental
impacts of agricultural production, such as the Conservation
Reserve Program (CRP) and the Conservation Compliance
provisions of the Food Security Act of 1985.
Groundwater quantity. While long-term trend data
for most of the Nation's groundwater stocks do not exist,
measurements of change in the water level of the High
Plains Aquifer indicates the effect of irrigation
on groundwater level. This aquifer provides approximately
one-third of the ground-water withdrawn for agricultural
irrigation in the U.S., and supports agricultural activity
in Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South
Dakota, Texas, and Wyoming.
Between 1940 and 1980, the region's average groundwater
level dropped a total of about 10 feet. Five of these
States experienced declines in their groundwater stocks,
while three experienced no change in their stocks over
this period. From 1980 to 1995, the average groundwater
level for the High Plains dropped 0.16 feet annually or
about 2.4 feet in total. An increase in groundwater stocks
was reported in one State and smaller declines reported
in three States.
Surface-water
quality has generally improved since 1974, when
monitoring began. In a 1974 survey, the EPA found that
only about 40 percent of the largest rivers in the United
States were safe enough for fishing and swimming. In 1994,
60 percent of the Nation's survey rivers, lakes, and estuaries
were safe enough for fishing and swimming. Still, agriculture
has been identified by the EPA as an important contributor
to surface-water impairment.
According to the National
Water Quality Inventory, agriculture is the leading
source of impairment in rivers (contributing to impairment
of 25 percent of the surveyed river miles), lakes (19
percent of lake acres, not including the Great Lakes),
and the fifth leading source of impairment to estuaries
(10 percent of surveyed estuary acres). Primary agricultural
pollutants are sediment and siltation, nutrients, pesticides,
salinity, and pathogens. For example, sediment and siltation
affect 18 percent of surveyed river miles and 10 percent
of lake acres. Nutrients affect 14, 20, and 22 percent
of surveyed river miles, lake acres, and estuaries.
Groundwater quality. The Nation's environmental
monitoring infrastructure cannot accurately depict trends
in U.S. groundwater quality. Recent chemical use trends
suggest that long-term improvements in groundwater quality
may occur. After pesticide use more than doubled between
1964 and 1982, it declined slightly due to a decline in
cropland acreage and the introduction of new
pesticide products that reduced pesticide application
rates. The picture with regard to potential chemical
toxicity is more complex. An index based on toxicity due
to long-term exposure to small doses shows an 89-percent
decline since 1964. An index based on acute exposure increased
by about 10 percent, and pounds of active ingredients
more than doubled.
Wetlands. The contiguous 48 States have lost about
half of all wetlands since 1780. In 1780, wetlands totaled
slightly over 220 million acres, compared with about 124
million acres in 1992. Most of the original and remaining
wetlands are in the Southeast, Delta, and Lake States.
The Corn Belt has lost nearly 90 percent of its original
wetlands, the Pacific States 75 percent, and the Plains
States 50 percent.
Between 1954 and 1992, 64 percent of all converted wetland
acreage supported agriculture. Available data suggest
that the rates of wetland loss in the 1980's were dramatically
lower than in earlier decades. For example, in 1954-74
and 1974-83, the net rate of wetland losses in the 48
States was 458,000 and 290,000 acres per year. From 1982
to 1992, the rate slowed to about 80,000 acres per year;
almost 11,000 acres per year moved out of agricultural
production and into wetlands.
Technology plays an important role in agricultural sustainability.
“Green technologies” (such as conservation tillage,
integrated pest management, enhanced nutrient management,
organic farming, and precision agriculture) are those
that can improve the environmental performance of agriculture
without reducing farm production or profits. However,
simply making a technology available does not guarantee
its adoption. Until markets are developed for the environmental
attributes associated with green technologies (such as
less erosion, improved water quality, and better wildlife
habitat), private markets will underutilize these technologies.
In general, research and development and the adoption
and diffusion of new technologies will be directed to
conserve those resources that are most scarce or highest
priced—the so-called induced innovation hypothesis.
Because the market prices of many environmental services
and natural resources are less than their true value to
society, there is less of an economic incentive to develop
or adopt technologies that conserve those resources.
In addition to the lack of markets, experience with
green technologies demonstrate that in addition to profitability,
three factors affect adoption:
- Structural barriers, including capital and labor availability,
may deter adoption.
- A diverse natural resource base, including varied
soil, water, and climatic resources, make it worthwhile
to adopt these technologies only in some instances.
- The economic risk of adopting new technologies may
inhibit adoption.
Because the economic and environmental implications of
green technologies vary by crop and region, no one technology
will be sustainable for every farmer in every part of
the country. Similarly, because barriers to adoption differ
across the country, there is a premium on knowledge about
regional adoption and diffusion constraints and an advantage
to a decentralized approach to research and development
and technology transfer.
The Major Distinctions
between Organic Farming Systems and Conventional Farming
Systems.
Organic farming systems differ fundamentally from conventional
ones in their primary focus on management practices that
promote and enhance ecological harmony. For example, organic
farmers use cultural and biological production practices
much more extensively than other farmers, according to
USDA survey results. The use of synthetic chemicals is
virtually excluded in crop production; antibiotic and
hormone use is prohibited in livestock production.
Under organic farming systems, the fundamental components
and natural processes of ecosystems, such as soil organism
activities, nutrient cycling, and species distribution
and competition, are incorporated as farm management tools.
For example, habitat needs for food and shelter are provided
for predators and parasites of crop pests, planting and
harvesting dates are carefully planned and crops are rotated,
and animal and green manures are cycled in organic crop
production systems.
Organic livestock production systems attempt to accommodate
an animals natural nutritional and behavioral requirements.
Livestock standards address the origin of each animal
and incorporate requirements for living conditions, access
to the outdoors, feed ration, and health care practices
suitable to the needs of particular species. Dairy cows
and other ruminants, for example, must be allowed access
to pasture.
Congress passed the Organic Foods Production Act of
1990 in order to establish national standards for organically
produced commodities. This legislation requires that all
except the smallest organic growers have to be certified
by a State or private agency accredited under national
standards. USDA implemented this legislation on October
21, 2002. The proposal addresses the methods, practices,
and substances used in producing and handling organic
crops, livestock, and processed foods, and may be viewed
at USDA's National
Organic Program website. Over 50 state
and private groups have been accredited by USDA to
provide organic certifications to growers and handlers.
Universities and other institutions in the United States
are examining the long-term economics of organic farming
systems through replicated field trial research. While
many of these projects are in their initial stages, several
have been running for a decade or more. Preliminary results
from some of these studies indicate that organic price
premiums are key in making organic systems more profitable
than conventional systems. Other studies are finding that
similar or enhanced yields under organic systems, combined
with sharply lower input costs, make these systems more
profitable even without price premiums. Examples of these
long-term farming systems trials include:
- Sustainable Agriculture
Farming Systems Project, at the University of California,
Davis, examined processing tomato, safflower, bean,
and corn production under conventional, low-input, and
organic systems for over sixteen years on a 28-acre
site in the Sacramento Valley, and is now examining
conservation tillage in alternate systems.
- Elwell
Agroecology Farm, in conjunction with the University
of Minnesota's Lamberton Experiment Station, began adding
long-term, organic cropping systems trials in 1989.
- The Living Field Laboratory, a project of the C.S.
Mott Chair of Sustainable Agriculture, Michigan Agricultural
Experiment Station, and others, was established in 1993
and is examining corn, soybean, and wheat production
under organic, conventional, and other management systems.
- USDA's Agricultural Research Service has also begun
investigating organic farming systems through long-term
farming systems trials and onfarm, participatory research.
Long-term trials are being conducted at USDA's Beltsville
Agricultural Research Center.
Trends in U.S. Acreage
Operated under Certified Organic Farming Systems
Organic farming has
been one of the fastest growing segments of U.S. agriculture
for nearly a decade. Certified organic cropland for corn,
soybeans, and other major crops more than doubled from
1992 to 1997, and doubled again between 1997 and 2001.
Two organic livestock sectors—poultry and dairy—grew
even faster. ERS collected data from State and private
certification groups to calculate the extent of certified
organic farmland acreage and livestock in the United States.
Farmers in 48 States dedicated 2.3 million acres of
cropland and pasture to organic production systems in
2001. Over 1.3 million acres were used for growing crops.
California, North Dakota, Minnesota, Wisconsin, Iowa,
Montana, and Colorado had the most organic cropland. Colorado,
Texas and Montana had the largest amount of organic pasture
and rangeland. USDA lifted restrictions on organic meat
labeling in the late 1990s, and by 2001, most of the States
were raising certified organic livestock.
While adoption of organic farming systems showed strong
gains between 1992 and 2001 and the adoption rate remains
high, the overall adoption level is still low—only
about 0.3 percent of all U.S. cropland and 0.2 percent
of all U.S. pasture was certified organic in 2001. Obstacles
to adoption by farmers include high managerial costs and
risks of shifting to a new way of farming, limited awareness
of organic farming systems, lack of marketing and infrastructure,
and inability to capture marketing economies. Still, many
U.S. producers are embracing organic farming in order
to lower input costs, conserve nonrenewable resources,
capture high-value markets, and boost farm income, especially
as prices fall for staple commodities.
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