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Regenerative Organic Farming: A Solution to Global Warming

Authors:
©2008 Rodale Institute
Regenerative Organic Farming:
A Solution to Global Warming
Tim J. LaSalle, Ph.D., CEO
Paul Hepperly, Ph.D., Director of Research and Fulbright Scholar
Rodale Institute
Introduction
Agriculture is an undervalued and underestimated climate change tool that could be one of the most
powerful strategies in the fight against global warming. Nearly 30 years of Rodale Institute soil carbon data
show conclusively that improved global terrestrial stewardship--specifically including regenerative organic
agricultural practices--can be the most effective currently available strategy for mitigating CO2 emissions.
Rodale Institute’s Farming Systems Trial® (FST) is the longest-running side-by-side comparison of organic
and conventional farming systems in the U.S. and one of the oldest trials in the world. It has documented
the benefits of an integrated systems approach to farming using regenerative organic practices. These
include cover crops, composting and crop rotation to reduce atmospheric carbon dioxide by pulling it from
the air and storing it in the soil as carbon. Results from these practices—corroborated at other research
centers that include University of California at Davis, University of Illinois, Iowa State University and USDA
Beltsville, Maryland, research facility—reiterate the vast, untapped potential of organic agricultural prac-
tices to solve global warming.
Agricultural carbon sequestration has the potential to substantially mitigate global warming impacts. When
using biologically based regenerative practices, this dramatic benefit can be accomplished with no de-
crease in yields or farmer profits. Even though climate and soil type affect sequestration capacities, these
multiple research efforts verify that practical organic agriculture, if practiced on the planet’s 3.5 billion
tillable acres, could sequester nearly 40 percent of current CO2 emissions.
Rodale Institute advocates a rapid, nationwide transition from today’s prevailing, petroleum-based farm-
ing methods to more advanced “post-modern“ systems incorporating best practices based on replicated
research. We call this approach regenerative organic agriculture to signify its focus on renewing resources
through complementary biological systems which feed and improve the soil as well as avoiding harmful
synthetic inputs. This is the full meaning of our preferred farming style in this discussion.
The problem with modern agriculture
Modern farming practices are one of the largest contributors to global warming.
Current farming practices are not sustainable for a number of reasons. Some Midwestern soils that in the
1950s were composed of up to 20 percent carbon are now between 1- and 2-percent carbon. This carbon
loss contributes to: soil erosion, by degrading soil structure; increasing vulnerability to drought, by greatly
reducing the level of water-holding carbon in the soil; and the loss of soil’s native nutrient value.
In addition, prevailing farming practices break down soil carbon into carbon dioxide that is released into
the atmosphere, greatly contributing to global warming. Surprising analysis of the nation’s oldest continu-
ous cropping test plots in Illinois showed that, contrary to long-held beliefs, nitrogen fertilization does not
build up soil organic matter. New data from U.S. government research show that with agriculture using
chemical fertilizers and herbicides, the U.S. food system contributes nearly 20 percent of the nation’s
carbon dioxide emissions. On a global scale, figures from the Intergovernmental Panel on Climate Change
(IPCC) say that agricultural land use contributes 12 per cent of global greenhouse gas emissions.
Other negative effects of the modern-farming paradigm include: nutrient overload in our waterways from
the use of synthetic nitrogen, loss of energy reserves due to the abundant use of petrol-based chemicals
(which put an increasing financial burden on farmers as oil prices rise), degradation of our soils (due to
mono-cropping that requires use of synthetic fertilizer for fertility) and animal health and welfare concerns.
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The soil solution: solving global warming…and more
Rodale Institute’s Farming Systems Trial (FST) was the first study that proved regenerative organic agricul-
tural practices store or sequester carbon in the soil by removing it from the air, thereby significantly revers-
ing the impact of global warming.
Regenerative organic farming methods can transform agriculture from part of the global warming problem
to a major part of the solution, by changing how we farm. Farmers can transition to new practices relatively
quickly and inexpensively using low-cost tools.
Carbon dioxide levels are minimized in summer when lush vegetation promotes a sponging action, and
are maximized in winter when plants go dormant. However, the greenhouse gas sponging ability of the soil
itself may make more of a difference than what’s growing on the land. On a global scale, soils hold more
than twice as much carbon (an estimated 1.74 trillion U.S. tons) as does terrestrial vegetation (672 billion
U.S. tons). Data from Rodale Institute and other studies indicate that regenerative and organic practices
can dramatically alter the carbon storage of arable lands, building soil “humic” substances (also known as
soil organic matter) that remain as stable carbon compounds for many years.
The key to greater, more stable carbon sequestration lies in the handling of soil organic matter (SOM). Be-
cause SOM is primarily carbon, increases in these levels will be directly correlated with carbon sequestra-
tion. While prevailing farming practices using synthetic inputs typically deplete SOM, regenerative farming
practices, including the integration of crop and animal production, build it.
Before forests and grasslands were converted to field agriculture, SOM generally composed 6 to 10 percent
of the soil volume, well over the 1- to 3-percent levels typical of today’s agricultural field systems. Building
soil organic matter by better nurturing our agricultural lands can capture the excess atmospheric carbon
dioxide and begin returning this lost carbon to the soil. Forests and rangelands hold a greater capacity for
carbon sequestration than the aboveground biomass measurements often used in equating their values.
Organically managed soils can convert carbon from a greenhouse gas into a food-producing asset. Soils
that are rich in carbon conserve water and support healthier plants that are more resistant to drought
stress, pests and diseases. Our studies of organic systems have shown an increase of almost 30 percent in-
soil carbon over 27 years. The petroleum-based system showed no significant increase in soil carbon in the
same time period and some studies have shown that these systems, in fact, may lose carbon.
Researchers are fleshing out the mechanisms by
which this soil carbon sequestration takes place. One
of the most significant findings is the high correlation
between increased soil carbon levels and very high
amounts of mycorrhizal fungi. These fungi help slow
down the decay of organic matter. Beginning with our
Farming Systems Trial, collaborative studies by the
USDA’s Agriculture Research Service (ARS) led by
David Douds, Ph.D., show that the biological support
system of mycorrhizal fungi are more prevalent and
diverse in organically managed systems than in soils
that depend on synthetic fertilizers and pesticides.
These fungi work to conserve organic matter by aggre-
gating organic matter with clay and minerals. In soil
aggregates, carbon is more resistant to degradation
than in free form and thus more likely to be con-
served. These findings demonstrate that mycorrhizal
fungi produce a potent glue-like substance called
glomalin that stimulates increased aggregation of soil
2
Mycorrhizal fungi structures enhance the ability of
plant roots to access soil moisture and nutrients,
produce stable compounds to sequester carbon di-
oxide as soil carbon , and slow decay of soil organic
compounds.
particles. This results in an increased ability of
soil to retain carbon. These findings are based on
analysis by ARS researchers at the Northern Great
Plains Research Lab in Mandan, North Dakota.
In Rodale Institute’s FST, soil carbon levels in-
creased more in the manure-based organic system
than in the legume-based organic system, presum-
ably because the manure stimulates the soil to
sequester carbon in more stable forms. The study
also showed that soil carbon depends on more
than just total carbon additions to the system, be-
cause cropping diversity or carbon-to-nitrogen ra-
tios of inputs may also have an effect. We believe
the answer lies in the decay rates of soil organic
matter under different management systems. The
application of soluble nitrogen fertilizers in the
petroleum-based system stimulates more rapid and complete decay of organic matter, sending carbon into
the atmosphere instead of retaining it in the soil as the organic systems do.
Reducing emissions, maintaining yield, cutting chemical run-off
Beyond the benefit of carbon sequestration, regenerative practices bring dramatic reductions in energy use
and carbon dioxide emissions.
An energy analysis of the FST shows a 33-percent reduction in fossil-fuel use for organic corn/soybean
farming systems that use cover crops or compost instead of chemical fertilizer. This translates to less
3
ORGANIC CONVENTIONAL
Soils improved over time through organic farming
methods gain in stored organic matter, which enhances
biological cycling of nutrients and management of water
for the benefit of crops.
Regenerative organic systems sharply reduce energy use, according to re-
search by David Pimentel, Ph.D.
0
50
100
150
200
250
Tillage
Conventional/Chemical
Organic/Regenerative
No-till Tillage No-till
231.7
199.2
121.6
77.5
Energy Used in Different Corn Production Systems
(gallons of diesel per acre)
greenhouse gas emissions as farmers adopt more regenerative production methods. Moreover, Rodale
Institute’s organic rotational no-till system can reduce the fossil fuel needed to produce each no-till crop in
the rotation by up to 75 percent compared to standard-tilled organic crops. Research beginning this year
at Rodale Institute will compare organic and petroleum-based no-till and tilled systems for the first time
within the ongoing FST regime.
Research findings have shown that the
biggest energetic input in a conventional,
modern corn and soybean system is nitrogen
fertilizer for corn, followed by herbicides for
both corn and soybean production. The abil-
ity of regenerative organic agriculture to be
a significant carbon sink and less dependent
on fossil-fuel inputs has long-term implica-
tions for global agriculture and its role in
air-quality policies and programs.
There are economic benefits beyond the
reduced input costs to growers. Our FST
showed that in all systems, corn and soy-
bean yields from the organic systems
matched the yields from conventional sys-
tems, except in drought years, when regen-
erative systems yielded about 30 per cent
more corn than the petroleum-based system. This yield advantage in drought years is due to the fact that
soils higher in carbon can capture more water and keep it available to crop plants.
Further, economic analysis by James Hanson, Ph.D., of the University of Maryland has shown that organic
systems in Rodale Institute’s FST are competitive in returns with conventional corn and soybean farming—
even without market-based organic premiums. These have been consistent for more than a decade, with
certified-organic crop prices ranging from 40 to 150 percent higher than standard crop prices.
Farming for carbon capture is also compatible with
other environmental and social goals, such as reduc-
ing erosion and minimizing impact on native ecosys-
tems.
This approach utilizes the natural carbon cycle to re-
duce the use of purchased synthetic inputs. Because
chemical fertilizers and pesticides are not used,
nutrient and chemical pollution in waterways is sig-
nificantly reduced. Not only does this translate into
long-term cleaner waterways, but it will also save in
environmental cleanup costs at the state and federal
level. The immensity of the societal cost of over-fer-
tilization is illustrated by the watersheds feeding into
the East Coast’s Chesapeake Bay. Despite millions of
dollars spent over the past 25 years to help farmers
reduce agricultural nutrient losses to the bay, roughly
300 millions pounds of nitrogen (39 percent from
agricultural sources) still reaches the bay annually.
4
ORGANIC CONVENTIONAL
Better water infiltration, retention and delivery to plants helps to
sustain yield during drought.
Organically improved healthy soil develops high levels
of complex organic compounds which are not readily
water soluble yet create micropores that help to man-
age water better than non-organic soils.
Research and proofs
Rodale Institute’s FST research was conceived as a way to test the assumptions about organic farming
methods in a systematic way that would be scientifically rigorous and practically relevant on a large scale.
Data from nearly three decades of research trials indicate that wide-scale implementation of established,
scientifically researched and proven practical farming methods will change agriculture from a global warm-
ing contributor to a global warming inhibitor, from a problem to a solution.
In the FST organic plots, carbon was sequestered into the soil at the rate of 875 lbs/ac/year in a crop rota-
tion utilizing raw manure, and at a rate of about 500 lbs/ac/year in a rotation using legume cover crops.
During the 1990s, results from the Compost Utilization Trial (CUT) at Rodale Institute—a 10-year study
comparing the use of composts, manures and synthetic chemical fertilizer—show that the use of composted
manure with crop rotations in organic systems can result in carbon sequestration of up to 2,000 lbs/ac/year.
By contrast, fields under standard tillage relying on chemical fertilizers lost almost 300 pounds of carbon
per acre per year. Storing—or sequestering—up to 2,000 lbs/ac/year of carbon means that more than 7,000
pounds of carbon dioxide are taken from the air and trapped in that field soil.
In 2006, U.S. carbon dioxide emissions from fossil fuel combustion were estimated at nearly 6.5 billion
tons. If 7000 lb/CO2/ac/year sequestration rate was achieved on all 434 million acres of cropland in the
United States, nearly 1.6 billion tons of carbon dioxide would be sequestered per year, mitigating close to
one quarter of the country’s total fossil fuel emissions.
This is the emissions-cutting equivalent of taking one car off the road for every two acres under organic re-
generative agricultural management, based on a vehicle average of 15,000 miles per year at 23 mpg (U.S.
EPA).
Organic agricultural practices are established and have been successfully commercialized, and we believe
that these methods are applicable in all scale operations as shown by farmers across the United States—
from family truck farms to commercial operations of many thousands of acres.
Four European countries have changed their emission-reduction targets for the Kyoto Protocol to include
contributions from organic agriculture policy based on Rodale Institute research. These are: the United
Kingdom, the Netherlands, Germany and Denmark. France has recently invited Paul Hepperly, Ph.D.—
research director at Rodale Institute—as a contributing scientist in their exploration of how organic agricul-
tural practices can be useful in fighting greenhouse gases.
Challenges to success
The technology, techniques and practices of regenerative organic agriculture are proven. Research provides
a sound basis for a national phasing out of environmentally harmful agricultural methods and phasing in of
regenerative organic systems.
Widespread implementation will dramatically benefit from additional support for research and development.
For example, more research is needed on the mechanisms responsible for the deep carbon sequestration
we see in organically managed agricultural soils and forests. The role of mycorrhizae and glomalin in soil
carbon retention requires further investigation, as do other biological mechanisms that result in greater
ability to sequester carbon naturally and improve soil properties. While these methods have been replicated
in a variety of soils and climates—from California to Senegal—further research is needed to systematically
measure carbon-sequestration results in various soils, climates and crops. To date, Rodale Institute’s FST
and ARS researchers at Beltsville have studied rotations using mainly grains, and UC Davis has tested cot-
ton and tomatoes.
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Measurement of carbon in soil is also key. For widespread commercialization, better tools are needed for
more predictive, quicker and more precise in-field soil-carbon measurement. Rodale Institute is currently
testing mineralization of soil nitrogen as a way to estimate soil carbon levels. Another opportunity that may
show great potential is analysis of satellite views of the earth to determine soil-carbon amounts. This ap-
proach requires taking into consideration yearly global carbon flux dynamics that track carbon and carbon
dioxide flows between atmospheric and biospheric (terrestrial and oceanic) sources, driven in part by sea-
sonal changes of photosynthetic activity.
Knowledge of carbon sequestration in forestry, range and pasture land needs to be combined and evalu-
ated with Rodale Institute’s research to gain a global terrestrial perspective on how much carbon could be
sequestered to mitigate global warming.
The economic implications of improved soil health, increased biodiversity, improved human health, water
savings, stream and bay cleanup, as well as climate change mitigation also need to be evaluated to help
shape public policy and international accords.
While research needs are clear, data from research trials and commercial practice have established that
the obstacles to nationwide implementation are neither technical nor economic. Rather, the largest ob-
stacles to success are human factors. Public education, cause marketing, retraining—these are the types
of programs needed to change behaviors in both farming practices as well as the way people shop and buy.
Consumers may be ahead of the market in this case. Demand for organic, no-pesticide and hormone-free
products in the United States has increased 20 percent or more each year for the past 14 years. Yet there
has only been a 3-percent increase in acres dedicated to organic practices.
Public education, training in organic regenerative farming and public policy
The current environmental emergency requires a major paradigm shift in the way we provide incentives for
our farmers. Incremental changes over a period of many decades are a prescription for continued global
warming and other environmental degradation.
Successful implementation of regenerative organic farming practices on a national basis will depend on
two factors: a strong bottom-up demand for change, and a top-down shift in state and national policy to
support farmers in this transition.
Rodale Institute’s experience in training thousands of farmers from around the world has proven that the
shift to regenerative farming practices is both doable and practical. It’s the decision to change that’s hard.
Government farm policy must be transformed in a way that incentivizes farmers and drives behavioral
change toward wide-scale adoption of regenerative farming practices. Success requires a sustained, multi-
faceted national public education campaign, training for farmers in regenerative agricultural methods and
legislative action.
From a climate change and global warming perspective alone, it would seem imperative that the 2012
Farm Bill replace the system of commodity payments with a program that rewards farmers for conservation
and other carbon-enhancing farm practices. Farmers should be paid on the basis of how much carbon they
can put into and keep in their soil, not only how many bushels of grain they can produce. Incentives will
encourage resource conservation and other carbon-enhancing means of producing crops for food, feed and
fiber. The current, antiquated method of paying for a single year’s crop would be eliminated.
Rodale Institute’s research demands a Farm Bill paradigm shift that invests in environmentally sound
systems and monetizes the ecological cost of fossil-fuel use (directly as fuel and indirectly in the manufac-
ture of synthetic inputs for non-regenerative systems). In 2008 global food demand is testing the capac-
ity of petroleum-dependent, export-focused commodity agriculture. This system has not served developed
6
nations as food prices soar—inflamed by biofuel demand and fuel prices—and greenhouse gas emissions
increase. It has especially hurt developing nations already struggling with food security issues.
Further, U.S. subsidies allow its exported commodity crops to be sold at artificially low prices in foreign
markets, running afoul of World Trade Organization (WTO) provisions for free trade. The United States has
lost every major challenge to these “trade distorting” subsidies before the WTO, but has yet to seriously
explore the EU approach of “green payments” that support ecological services apart from yield.
The following chart outlines some comparative differences between the current Farm Bill structure—which
rewards high-volume production of commodities such as wheat, soybeans, corn and oilseeds—and the
proposed carbon-reward system of incentives.
7
CARBON FOCUSED
Improves crop biodiversity – Rewarding all
farmers, regardless of crops & acreage, for
carbon stored will stimulate a variety of crops,
rather than traditional commodity crops. Crop
rotations also allow soil to replenish itself
Rewards “green” practices – Regenerative
methods reduce greenhouse gas emissions,
avoid waterway pollution, limit erosion, and
improve soil health
Economically independent – By creating an
integrated system that doesn’t depend on
artificial inputs tied to historically increasing
petroleum prices, farmers are more economi-
cally independent
Long-term strategic land use – More perennial
crops, including pasture and trees, focused on
land stewardship to create a holistic farm plan
Reduces Erosion – More acres covered with
growing crops for more months of the year
reduce the risk of soil erosion
Energy saving – Reduces or eliminates petro-
leum-dependent chemical fertilizer and pesti-
cide inputs. Integrated systems reduce need for
artificial inputs with high energy costs.
Spurs independent, entrepreneurial seed
production – Increases demand for a broader
range of crop seeds with carbon benefits, spur-
ring new growth in regional and entrepreneurial
seed companies that are often independent of
input producers.
Opens marketplace – Creates non-traditional
opportunities to enter commercial markets,
meeting surging demand for local and regional
production in the Midwest and East. Allows
more diverse farmers into the market
COMMODITY FOCUSED
Limits crops – Limiting financial incentives to
commodity crops – corn, soybeans, wheat, rice,
cotton – directs farmers to choose same small
number of crops. Growing single crops each
year also depletes nutrients from the soil
Environmentally harmful – Petroleum-based
inputs release greenhouse gases, leach nitro-
gen and phosphorus into the water and deplete
naturally occurring soil nutrients, making it
more dependent on chemical fertilizer
Petroleum-industry dependent – Farmers’
profits are tied to increases in petroleum-based
fertilizer and pesticide prices,
creating a cycle of dependency
Short-term field focus – Annual crops (tilled
and no-till) are the main focus on a year-to-year
basis.
Erosion-prone – Current systems that leave
fields fallow for large portions of the year are
much more vulnerable to soil loss
High energy use – Continues and increases
use of petroleum-dependent chemical fertilizer
and pesticide inputs that take a great deal of
energy to produce and transport.
Generates dependence on monopolistic seed
and input companies – Continues concentra-
tion of seed production focused on high-input
varieties that trap farmers into cycle of depen-
dency with a few large companies producing a
small variety of crops.
Discourages new farmers and innovative crop
production – Commodity programs include
strong disincentives that discourage commodity
crop farmers to diversify.
Section Seven: A Call to Action
Compared to expensive, experimental, high-technology projects, global transition to biologically based
farming can be achieved without new technology or expensive investment. Changing the emphasis from
commodity to carbon will profoundly affect the economic drivers at the farm level. Farmers will creatively
adapt to this economic prescription and shift to ecologically sound agricultural practices as they fulfill
consumer demand, supported by a practical policy that makes a transition to these practices economically
feasible.
With a problem so dire, a need so urgent, and a solution so available, the path to responsible terrestrial
stewardship is clear. And because the practices of 21st Century regenerative organic agriculture are scal-
able globally, it’s a solution that can be adapted all over the world.
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Addendum
Rodale Institute: An overview of our work
with organic and sustainable farming
Summary
Rodale Institute is located on a 333-acre certified organic farm in Kutztown, Pennsylvania and has spent
60 years doing extensive research to provide farmers with the know-how, tools and techniques they need
to succeed, policy-makers the information they need to best support our farmers and consumers with the
resources they need to make informed decisions about the food they buy and eat both in the United States
and abroad.
From aquaculture and amaranth studies to vetch varietals trials and design and experimentation with a
cutting-edge roller-crimper tool for low-cost, low-input no-till, the on-farm and collaborative research of
the Rodale Institute has spanned the width and breadth of agriculture. The farm is perhaps best known
for its Farming Systems Trial® (FST), the United State’s longest-running scientific experiment specifically
designed to compare organic and conventional farming practices.
Brief History
The Institute was created by visionary J.I. Rodale who moved from New York in the late 1930s to rural
Pennsylvania, where he was able to realize his keen personal interest in farming. He learned about organic
food-growing concepts being promoted by Lady Eve Balfour and Sir Albert Howard and theorized, based on
their work and his own observations, that to preserve and improve our health we must restore and pro-
tect the natural health of the soil. Developing and demonstrating practical methods of rebuilding natural
soil fertility became J.I. Rodale’s primary goal when World War II’s sudden shortage of nitrogen fertilizer
– diverted to making munitions – exposed the natural nutrient poverty of the nation’s soil. In 1947, J.I.
founded the Soil and Health Foundation, forerunner to the Rodale Institute. He also created successful
periodicals, including Health Bulletin, Organic Farming and Gardening and Prevention magazines.
The concept of “organic” was simple but revolutionary in the post World War II era. Manure, cover crops
and crop mixtures were standard practices through World War I, but chemical fertilizers, pesticides, herbi-
cides, artificial ingredients, preservatives and additives for taste and appearance in the years since the war
had rapidly changed agriculture. As J.I. Rodale communicated the idea of creating soil rich in nutrients
and free of contaminants, however, people began to listen and acceptance grew.
J.I. Rodale died in 1971. His son Robert expanded the farm and health-related research with the pur-
chase of the 333-acre farm near Kutztown, Pennsylvania. With his wife Ardath, Robert established what
is now the Rodale Institute and an era of research began that continues today. Powerful testimony by
Robert Rodale, and the farmers and scientists who swore by the sustainable methods pioneered at Rodale,
convinced the U.S. Congress to include funds for regenerative agriculture in the 1985 Farm Bill. Today,
federal, state and local governments, land-grant universities and other organizations nationwide are pursu-
ing regenerative agriculture research and education programs.
When Robert Rodale was killed in a traffic accident in Moscow in 1990, Ardath Rodale became the Insti-
tute chairman and John Haberern became president. In 1999 Robert and Ardath Rodale’s son, Anthony
became chairman of the board. Anthony and Florence, his wife, developed outreach efforts to children
during their period of active program involvement before Anthony became an international ambassador for
the Rodale Institute’s mission. Board member Paul McGinley became co-chair of the board with Ardath in
2005.
Timothy J. LaSalle became the first CEO of the Institute in July 2007, bringing decades of experience in
academic, agricultural and non-profit leadership to the task. Under his guidance, the Institute champions
organic solutions for the challenges of global climate change, better nutrition in food, famine prevention
and poverty reduction.
1991 1993 1996 2002 2003 2004 2005 2006 2007
The Rodale Institute
sponsors the world's
first International
Conference on the
Assessment and
Monitoring of Soil
Quality. More than
two dozen specialists
from five countries
participate.
Rodale Institute's
Compost Utilization
Trial begins
comparing the use
of composts,
manures and
synthetic chemical
fertilizer.
Rodale Institute's
article in Nature
shows organic
management
conserves carbon
and nitrogen in the
soil promoting
productivity. ARS
soil scientist Sara F.
Wright discovers
glomalin, soil "super
glue," implicated as
a key component of
agricultural carbon
sequestration.
Organic systems in
Rodale Institute's
Farming Systems
Trial are shown to
have significantly
higher yields under
severe drought and
environmental
stresses.
Rodale Institute
research depart-
ment calculates
carbon sequestra-
tion in the Farming
Systems Trial and
develops white
paper on the
significant impact
regenerative
farming technique
have on mitigating
global warming.
Rodale Institute research
department calculates
carbon sequestration in
the Compost Utilization
Trial and finds
overwhelming evidence
that regenerative farming
techniques can become
the single largest wedge
to actively combating
global warming.
Rodale Institute,
Cornell University,
Maryland University
and USDA ARS show
carbon and nitrogen
sequestration values,
economics and
energy efficiency of
organic agriculture in
Bioscience article.
Anthony Rodale
becomes chairman
emeritus for the
Rodale Institute, and
Ardath Rodale and
Paul McGinely take
over as co-chairs.
University of
California Davis
shows carbon
sequestration
levels in San
Yoaquin Valley
similar to Rodale
Institute findings.
University of Illinois at Morrow
Plots shows nitrogen fertilizers do
not contribute to carbon sequestra-
tion corroborating Rodale Institute
Compost Utilization Trial results.
Henry A. Wallace Agricultural
Research Center shows that
organic farming can yield better
soil quality and sequestration
results compared to no-till alone.
Timothy J. LaSalle joins the Rodale
Institute as the first CEO. Under his
leadership, the Institute champions
organic solutions for the challenges
of global climate change, better
nutrition in food, famine prevention
and poverty reduction.
©2008 Rodale Institute
... Furthermore, an article on regenerative organic agriculture and climate change states that A Down-to-Earth solution to Global warming could sequester more than 100% of current annual CO 2 emissions with a switch to widely available and inexpensive organic management practices, termed as ‗regenerative organic agriculture' (LaSalle and Hepperly, 2008). This opens the avenue of use of nanotechnology for organic management practices as that have been observed with this technology in increasing benefits for food industrywithout any negative public opinions towards its use (Sekhon, 2010). ...
Thesis
Development of sustainable and ecofriendly agriculture practices for amelioration of complications arising from climate change, food toxicity and food scarcity are major concerns of modern world. Among several approaches application of silica appears to be promising because of recent research findings in corroborating multibeneficial effects on plants which could be a silver lining towards sustainable agriculture, however, its solubility is of concern. Taking this into an account, isolation of biogenic silica nanoparticles from rice husk using modified sol-gel method were carried and confirmed though XRD, SEM and FTIR performed at NIMS, Japan. The extracted silica nanoparticles size was found to be between 50-100 nm and it was found to be amorphous in nature. Resuspending these isolated silica nanaoparticles gave around 65% molybdate reactive silica indicating that with proper solubilization technology employed it could potentially exhibit the inherent trait of supporting plants growth as have been elucidated by several researchers. For future development as application in agriculture and forestry the effects of isolated nanoparticles were examined in three reference plants, Oryza sativa (rice) for staple food, Amomum subulatum as shrub and high value crop and Paulownia tomentosa as woody material for carbon capture, in tissue culture model in controlled environment. The ANOVA analysis performed showed significant impacts of silica nanoparticles in root length and leaves number in rice. There was also a substantial increase in the catalase activity (max.0.6μg/min/g fresh weight) and ascorbate activity (max.8.5μg/min/g fresh weight) with increased chlorophyll content approx.. 13μg/g . The results, however, were not linear and same was observed in case of Paulownia whereby the best concentration was determined to be 1g/l. This lower concentration in Paulownia could be a typical characteristic of silica in woody plant interaction that hasn’t been reported yet to our knowledge or could be the silica we incorporated could not be totally soluble driving us into a search for an alternative to solubilize the silica entirely. This was the third part of our experiment i.e. isolation of silica solubilizing bacteria from soil. A potent strain of Paenibacillus mucilaginous was our organism of focus due to its capability of solubilizing silica naturally, higher CO2 sequestration and a role model in degrading PAHs. Selective starch and naphthalene media were utilized to screen the different strains of the bacteria following microbial characterization and confirming through molecular detection using 16sRNA, gyrB and esterase like protein gene amplification. One strain K1-4 out of 36 different strains from 9 different soil samples from Illam and Kalinchowk as a confirmed P. mucilaginosus from the preliminary results. Further, silica solubilization ability yet to be performed. Moreover, the material science, biochemical, plant tissue culture, microbiological and molecular approaches were integrated to address the issue of agricultural productivity and environmental concerns. It is presumed that the present works could not be sufficient in addressing such daunting tasks but could be a step forward where further studies and researches could give more substantial solutions to these issues.
... Climate change as a result of increased concentrations of greenhouse gases in the atmosphere has become an important issue in recent decades, with carbon dioxide (CO 2 ) being the main greenhouse gas responsible [1]. Agriculture plays an important role in mitigating climate change by reducing atmospheric greenhouse gas emissions, through carbon sequestration in soils and plants. ...
Article
Full-text available
Climate change as an implication of global warming due to the influence of increasing concentrations of greenhouse gases in the atmosphere has become an important issue in recent decades. Organic farming plays an important role in mitigating climate change by reducing atmospheric greenhouse gas emissions through increased soil carbon sequestration. This study was designed to compare soil carbon sequestration levels between conventional and organic vegetable farming fields in Bali, Indonesia. Soil samples were taken from organic fields and conventional fields in pairs. Variables of soil organic carbon, soil labile carbon, and soil bulk density are measured. Vegetable yields were estimated by fresh weights from a quadrant of 45 plants (1.12 m ² ) in each farming system, which is then converted to the fresh weight per hectare. The results from soil analysis indicate that organic farming leads to soil with significantly higher soil carbon storage capacity than conventional farming. The labile C fraction shows a more significant increase compared to total C. Organic farming can increase by 1.13 tons C per hectare per year compared with the conventional farming system. The use of manure compost as an alternative in vegetable fields of Bali has resulted in increased soil organic carbon storage and gross benefits for farming. Although more research is needed on the actual emissions of CO ² gas from organic and conventional farming, this research can be used as an early indication that organic vegetable farming system can increase the mitigation of global warming, and build sustainable agriculture in Bali, Indonesia.
... Hoy día, está ampliamente demostrado que la adopción de ciertas prácticas de manejo permite aumentar el carbono orgánico almacenado con el fin de aprovechar la gran capacidad que presentan los suelos agrícolas como sumidero [6][7][8][9][10]. Los sistemas de producción agrícola y en particular, los de conservación, presentan un gran potencial para capturar y almacenar carbono [11,12], generando efectos positivos adicionales: los suelos con mayor cantidad de materia orgánica tendrán mejor capacidad de infiltración del agua, mejor estructuración, resistirán mejor los procesos erosivos y brindarán beneficios a la productividad y sostenibilidad agrícola [13,14]. A su vez, en un contexto de cambio climático, el foco de los estudios recientes sobre la materia orgánica de los suelos apunta a determinar no solo su impacto sobre la productividad sino su función como posible destino del carbono de la atmósfera [15,16]. ...
... En la actualidad, uno de los principales focos de atención de los debates agrarios se ha centrado en aportar evidencias y valorar en qué medida la agricultura ecológica puede ser una alternativa sostenible para la producción de alimentos (Altieri, 1987;Gliessman 2000;Sarandón, 2002). Una cuestión fundamental de análisis han sido las contribuciones de la agricultura ecológica a la eficiencia energética en comparación con la convencional (Ziesemer, 2007;Smith et al., 2013) y sus aportaciones a la lucha contra el cambio climático (LaSalle, 2008;Borron, 2006;Badgley et al., 2007;El-Hage & Scialabba, 2010). Un estudio realizado por el Ministerio Británico de Agricultura, Pesca y Alimentación demuestra que los requerimientos energéticos por hectárea de la producción de trigo ecológico son un 40% menores que en un manejo convencional, 50% en el caso de las zanahorias, 54% para las patatas, 65% para las cebollas, etc. (MAFF, 2000). ...
Article
Full-text available
Una de las características más importantes de la agricultura es su capacidad para transformar la energía y generar "excedentes" energéticos con diversos usos (alimentación humana, animal, fertilización, etc.). Estos excedentes energéticos son potencialmente mayores en la agricultura ecológica como resultado del menor uso de insumos vinculados a la energía fósil. Los cereales y las leguminosas son cultivos que se caracterizan por altos outputs y balances de energía, ambos indicadores fundamentales de la sostenibilidad agraria. En este trabajo se analiza, tanto en términos monetarios como energéticos, el comportamiento de los cultivos extensivos ecológicos en Andalucía para el año 2005. Así mismo, se realiza un análisis comparativo entre los resultados energéticos obtenidos en el presente estudio y los aportados en otros estudios nacionales e internacionales. El balance monetario y energético de los cultivos extensivos se estimó en 2,47 y 3,65 respectivamente. Este último se incrementa hasta 6,49 si solamente se tiene en cuenta el uso de energía no renovable. En términos comparativos con cultivos convencionales, los resultados muestran un elevado grado de eficiencia energética. Palabras claves Agricultura sustentable, agricultura ecológica, análisis energéticos, eficiencia energética, cereales y leguminosas Pérez Neira, David; Marta Soler Montiel; Xavier Simón Fernández (2015) Energy sustainability and economic viability of organic extensive herbaceous crops in Andalusia. Rev. Fac. Agron. Vol 114 (1): 15-26 One of the most important characteristics of agriculture is its capacity to transform energy and generate energy "surpluses" with various uses (human food, animal feed, fertilization, etc.). These energy surpluses are potentially larger in ecological agriculture as result of low fossil fuel inputs related. Cereals and legumes are crops with high energy balance and output, both key agrarian sustainability indicators. This work analyses the behaviour of ecological extensive crops in Andalusia (2005), in both monetary and energy terms. In addition, a comparative analysis is made of the energy results obtained in the present study and those contributed by other national and international studies. The monetary and energy balance of extensive crops is estimated at 2.47 and 3.65, respectively. When only the use of non-renewable energy is taken into consideration, the energy balance increases and reaches 6.49. In comparative terms, the results show a high degree of energy efficiency.
... The strategy of HYVP worked well in increasing the yield but failed to retain the genetic base resulting in loss of indigenous varieties as well as useful conventional agricultural practices (Shiva 1993). On the other hand, shift of traditional methods to monoculture technique is known to degrade quality of soil making it prone to soil erosion and hence rendering it unproductive (LaSalle and Hepperly 2008). The unprecedented use of fertilizers also increased drastically during this period which led to imbalance in the threshold of nitrogen (N), phosphorous (P), and potassium (K) contents and loss of other micronutrients in soil (Das and Mandal 2015). ...
Chapter
Full-text available
Increasing food demand, with growing population, has been a major concern throughout the globe. The aim can only be achieved with the onset of next green revolution being much defined by sustainable approaches. The past green revolution had its negative impact due to excessive use of agrochemicals contaminating the environment and further challenging the food security. Henceforth, designing the blueprint of next green revolution requires the application of effective and sustainable approaches which enhance the yield of plants while still maintaining the decorum of sustainability. In this regard, microbes have been concluded as the best players finding their roles in plant growth promotion and also stress management. Currently, there are several bacterial-, fungal-based inoculants available in the market along with genetically modified organisms, forming the base of upcoming green revolution. Thus, the future of sustainable agriculture is related to the efficiency and action of these microbes.
... N2O may be considered the main greenhouse gas; the organic farming system usually produces less N2O and carbon dioxide because of its lower inputs [67]. LaSalle [68] stated that if the organic farming system was applied throughout the USA, it would lead to higher carbon sequestration in the soil and reduce carbon dioxide emissions by one-fourth. There are more possibilities for mitigating the environmental burden, such as replacing existing cultivations and crops (e.g., maize) with some other suitable crops, e.g., certain perennial grass species that have suitable properties [26,45]. ...
Article
Full-text available
The domestic biogas market has been developing rapidly, and legislation (The Act) supporting the use of renewable energy sources has come into force. In light of this act and investment support from national programs co-financed by the European Union (EU), the total number of biogas plants has recently increased from a few to 670. The total capacity of electricity generation of those 670 installed plants exceeds 360 Megawatts (MW) (as of mid-2018). Such dynamic growth is expected to continue, and the targets of the National Renewable Energy Action Plan are projected to be met. The use of waste material, which was urgently needed, was the original aim of biogas plants. However, in certain cases, the original purpose has transformed, and phytomass is very often derived from purpose-grown energy crops. Maize is the most common and widely grown energy crop in the Czech Republic. Nevertheless, maize production raises several environmental issues. One way to potentially reduce maize’s harmful effects is to replace it with other suitable crops. Perennial energy crops, for example, are possible alternatives to maize. A newly introduced species for the conditions of the Czech Republic, Elymus elongatus subsp. ponticus cv. Szarvasi-1, and some other well-known species—Phalaris arundinacea L. and Miscanthus × giganteus—are suitable for Czech Republic climate conditions. This paper presents the findings of the research and evaluation of environmental, energy-related, and economic aspects of growing these crops for use in biogas plants. These findings are based on 5-year small-plot field trials. The energy-related aspects of producing Elymus elongatus subsp. ponticus cv. Szarvasi-1, Phalaris arundinacea L., and Miscanthus x giganteus are reported on the basis of experiments that included measuring the real methane yield from a production unit. The economic analysis is based on a model of every single growing and technological operation and costs. The environmental burden of the individual growing methods was assessed with a simplified life cycle assessment (LCA) using the impact category of Climate Change and the SimaPro 8.5.2.0 software tool, including an integrated method called ReCiPe. The research findings show that Szarvasi-1 produces 5.7–6.7 Euros (EUR) per Gigajoule (GJ) of energy, depending on the growing technology used. Szarvasi-1 generates an average energy profit of 101.4 GJ ha−1, which is half of that produced by maize (214.1 GJ ha−1). The environmental burden per energy unit of maize amounts to 16 kg of carbon dioxide eq GJ−1 compared with the environmental burden per energy unit of Szarvasi-1, which amounts to 7.2–15.6 kg of CO2 eq GJ−1, depending on the yield rate. On the basis of the above-mentioned yield rate of Szarvasi-1, it cannot be definitively recommended for the purpose of biogas plants in the Czech Republic.
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On the Ground •Sustainable beef is a socially responsible, environmentally sound, and economically viable product that prioritizes planet, people, animals, and progress. Beef sustainability requires awareness of the complex relationships among these three pillars. •In practice, sustainability to beef farmers and ranchers is about taking care of the animals, land, and water, while being a good neighbor and community member, and maintaining profitability. The beef industry has made improvements across these three areas of sustainability, in all sectors of the industry, from the cow-calf level to the packer phase. •The removal of beef cattle from grazing lands would effectively eliminate the beef industry, which would have a ripple effect on other industries that serve as input suppliers across the beef supply chain, while also eliminating critical social, economic, and environmental services provided by grazing cattle. •We describe the science on the economic, social, and environmental benefits of grazing cattle on grazing lands, and discuss the sustainability impacts of eliminating the beef industry in the U.S.
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Covid-19 has highlighted the destructiveness of modern agro-industry upon biosphere and humanity. Its contribution to environmental degradation intertwines with socio-economic inequality and labour exploitation. There are increasing calls for a green new deal (GND) to counter these dangers. This article argues that a GND for agriculture must combat environmental degradation, social inequality and labour exploitation, rather than aim to re-boot capitalist economies. This article identifies a number of areas for discussion and political action - reorientation of state subsidies, workers' rights, agrarian reform, the decommodification of food, agroecology, possibilities for urban agriculture, the application of new technologies, and rewilding.
Conference Paper
Organic agriculture is a production management system which promotes and enhances agro-ecosystem health, including biodiversity, biological cycles, and soil biological activity. It is a system that begins to consider potential environmental and social impacts by eliminating the use of synthetic inputs, such as synthetic fertilizers and pesticides, growth hormones, antibiotics, veterinary drugs, genetically modified seeds and breeds, preservatives, additives and irradiation. Organic farming has potential for reducing some of the negative impacts of conventional agriculture on the environment and contributes to rural development and economy. Organic farming contributes to rural development and economy. Advent of intensive agricultural practices involves heavy use of chemical fertilisers and pesticides, which created problems of deterioration in natural resources and environmental problems threatening sustainability of production systems and human health. In this review, the most important reasons that necessitate organic agriculture such as environmental problems, performance and soil quality, groundwater pollution and nitrate accumulation, global nitrogen cycle and N losses, greenhouse gases, pesticide residues, excessive fossil energy use, economic and social concerns, and biological diversity are discussed.
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Various organic technologies have been utilized for about 6000 years to make agriculture sustainable while conserving soil, water, energy, and biological resources. Among the benefits of organic technologies are higher soil organic matter and nitrogen, lower fossil energy inputs, yields similar to those of conventional systems, and conservation of soil moisture and water resources (especially advantageous under drought conditions). Conventional agriculture can be made more sustainable and ecologically sound by adopting some traditional organic farming technologies.
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The origins and composition of soil organic matter (SOM) are still largely uncertain. Arbuscular mycorrhizal fungi (AMF) are recognized as indirect contributors through their influence on soil aggregation, plant physiology, and plant community composition. Here we present evidence that AMF can also make large, direct contributions to SOM. Glomalin, a recently discovered glycoprotein produced by AMF hyphae, was detected in tropical soils in concentrations of over 60 mg cm-3. Along a chronosequence of soils spanning ages from 300 to 4.1 Mio years, a pattern of glomalin concentrations is consistent with the hypothesis that this protein accumulates in soil. Carbon dating of glomalin indicated turnover at time scales of several years to decades, much longer than the turnover of AMF hyphae (which is assumed to be on the order of days to weeks). This suggests that contributions of mycorrhizae to soil carbon storage based on hyphal biomass in soil and roots may be an underestimate. The amount of C and N in glomalin represented a sizeable amount (ca. 4-5 percent) of total soil C and N in the oldest soils. Our results thus indicate that microbial (fungal) carbon that is not derived from above- or below-ground litter can make a significant contribution to soil carbon and nitrogen pools and can far exceed the contributions of soil microbial biomass (ranging from 0.08 to 0.2 percent of total C for the oldest soils).
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13 CO2 and followed both tally distinct in terms of interactions with soil microbial root- and shoot-derived C in total soil organic C (SOC) and labile C systems because C inputs from roots include root pro- pools for the first growing season following hairy vetch incorporation. duction, turnover, and exudation. The influence of roots At the end of the growing season, nearly one-half of the root-derived on SOC pools could be relatively greater than the influ- C was still present in the soil, whereas only 13% of shoot-derived C ence of aboveground C inputs because of the continuous remained. A greater proportion of root-derived C was found as oc- release of C from roots and the complex nature of the cluded POM and associated with the clay and silt fraction. Greater associated with the use of green manures. Furthermore, on the basis In SOM dynamics studies, particular attention is given of these findings, we hypothesize that the greater retention of root- to the POM fraction. This fraction, composed mainly derived C in the first 6 mo of decomposition will increase the persis- tence of this C in SOM in the long term. of plant residues in different stages of decomposition, is regarded as a labile pool of SOM and is very sensitive to changes in C input and loss with time (Christensen,
Article
Composts made from rural and urban residues are increasingly available. Farmers wishing to use these materials need to know how they will perform as crop nutrient sources. The objectives of this field experiment were to evaluate compost as an N source, and to track the effects of compost application on NPK budgets. Four composts of various feedstocks, maturity, and nutrient content were compared to raw dairy manure (RDM) and conventional mineral fertilizer (CNV). A 3-year rotation of corn (Zea mays L.), bell pepper (Capsicum annum), and small grain was established, with all crops present every year. Treatments were applied on an N-equivalent basis, using a 40% availability factor for compost and 50% for RDM. Yields from compost-amended corn were comparable to RDM and CNV by the second year. Pepper, a less N-demanding crop, had no significant yield differences among treatments for the three years. The manure-based compost treatments had the highest P and K surplus after three years, showing that loading levels of these nutrients need consideration when using compost to satisfy crop N needs. Rotations can be designed to extract more P and K, but more practical for the long-term would be reducing compost additions and substituting an additional N source such as a legume.
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This book is a single-volume treatment of the biochemical cycles in soil. It examines all major aspects of nutrient cycling, including fluxes with other ecosystems, biochemical pathways and transformation, gains and losses, chemical fixation reactions, and plant availability. It integrates environmental issues into the classical treatment of cycling processes. Two chapters are devoted exclusively to pollution of the environment.
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The 1999 severe crop season drought in the northeastern US was followed by hurricane-driven torrential rains in September, offering a unique opportunity to observe how managed and natural systems respond to climate-related stress. The Rodale Institute Farming Systems Trial has been operating since 1981 and consists of three replicated cropping systems, one organic manure based (MNR), one organic legume based (LEG) and a conventional system (CNV). The MNR system consists of a 5-year maize–soybean–wheat–clover/hay rotation, the LEG of a 3-year maize–soybean–wheat–green manure, and the CNV of a 5-year maize-soybean rotation. Subsoil lysimeters allowed quantification of percolated water in each system. Average maize and soybean yields were similar in all three systems over the post-transition years (1985–1998). Five drought years occurred between 1984 and 1998 and in four of them the organic maize outyielded the CNV by significant margins. In 1999 all crop systems suffered severe yield depressions; however, there were substantial yield differences between systems. Organic maize yielded 38% and 137% relative to CNV in the LEG and MNR treatments, respectively, and 196% and 152% relative to CNV in the soybean plots. The primary mechanism of the higher yield of the MNR and LEG is proposed to be the higher water-holding capacity of the soils in those treatments, while the lower yield of the LEG maize was due to weed competition in that particular year and treatment. Soils in the organic plots captured more water and retained more of it in the crop root zone than in the CNV treatment. Water capture in the organic plots was approximately 100% higher than in CNV plots during September's torrential rains.
Article
 Land productivity, along with improvement or maintenance of soil health, must be evaluated together to achieve sustainable agricultural practices. Winter wheat-fallow (W-F) has been the prevalent cropping system in the central Great Plains for 60 years where moisture is a limitation to crop production. Alternative cropping systems show that producers can crop more frequently if residue management and minimum tillage are used. The impact of different crops, crop rotations and tillage management practices on soil quality was assessed by measuring aggregate stability and glomalin production by arbuscular mycorrhizal (AM) fungi in soil from cropping trials established in 1990. Crops were wheat (W), corn (C), proso millet (M), and sunflower (S). Rotations sampled were W-F, W-C-M, W-C-M-F, W-C-F, and W-S-F. In the same area as the cropping trials, soils were taken from a perennial grass (crested wheatgrass) and from a buffer area that had been planted to Triticale for the past 2 years but prior to that had been extensively plowed for weed control. We found that aggregate stability and glomalin were linearly correlated (r=0.73, n=54, P<0.001) across all treatments sampled. Highest and lowest aggregate stability and glomalin values were seen in perennial grass and Triticale soils, respectively. Aggregate stability in W-S-F was significantly lower than in the other crop rotations (P≤0.03), while W-C-M had significantly higher glomalin than the other rotations (P<0.05). Differences between crop rotations and the perennial grass indicate that selected comparisons should be studied in greater detail to determine ways to manage AM fungi to increase glomalin and aggregate stability in these soils.