“SOS: Save Our Soil” Shows
Innovative Approaches to Sustainable Agriculture
April 04, 2015
Story at-a-glance
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New video report shows how soil health affects the
planet’s climate and ecosystem, and features a few
innovative farmers with game-changing approaches to
sustainable agriculture
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The world’s soils have lost 50 to 70 percent of
their carbon, much of which is now in the atmosphere
as carbon dioxide
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Humus, different from compost, nourishes soil for
centuries and develops naturally if enough organic
matter is added and the soil remains undisturbed
By Dr. Mercola
“The nation that destroys its soil
destroys itself.”
–Franklin D. Roosevelt, 1937
America has not heeded the warning Roosevelt issued nearly 80
years ago. Precious soils are being decimated daily by misguided
reliance on industrialized agriculture and synthetic chemicals,
which disrupt its delicate ecosystem.
The soils are poisoned with
chemical fertilizers and pesticides, and allowed to wash away
from overfarming, overgrazing, and erosion. Once teeming with life,
our prairies and grasslands are being turned into lifeless dust
fields.
The PBS documentary “SOS: Save our Soil,” part of its Food
Forward series,1
highlights a few “food rebels” who are finding innovative ways to
create a more sustainable food system, including making humus
compost out of grass stubble and turning chicken litter into
biochar.
The top six inches of soil are the most precious yet least
understood ecosystem on Earth. In order to appreciate its importance
to our very survival, you first must understand the role carbon
plays in maintaining the ecological balance of our entire planet.
Conventional agriculture that relies on tilling and monocrops
decimates the top soil and is responsible for massive losses every
year. So much so that some predict that most of the topsoil in the
US will be lost in the next two generations.
Have We Forgotten We’re Carbon-Based Life Forms?
All life on earth is carbon-based, yet we seem to ignore carbon’s
importance. Even
soil microbes need carbon to flourish, which is why slow and
steady carbon depletion from our soils will inevitably lead to
ecological collapse.2,3
Deprived of carbon and critical microbes, soils become sterile;
devoid of the microbial ecosystem.
The problem of carbon depletion in soils is not limited to the
US. The world’s cultivated soils have lost 50 to 70 percent of their
original carbon, much of which has been oxidized upon exposure to
air to become carbon dioxide (CO2).4
One of the largest factors driving this carbon depletion problem
is the food/agriculture industry, particularly tilling, lack of
cover crops, monocropping, genetically engineered (GE) crops, and
their massive dependence on synthetic chemicals, which quickly
decimate topsoil.
Meanwhile, carbon dioxide emissions continue to rise. In 2012
alone, 35.7 billion tons of this greenhouse gas entered the
atmosphere.5
Some CO2 is absorbed by the oceans, plants, and soil—healthy soil is
a bountiful carbon reservoir.
Scientists have recently discovered how organic carbon is stored
in soil—it binds only to certain soil structures. Soil's
capacity to absorb CO2 is directly related to its health; therefore,
soil preservation and restoration needs to be incorporated into
today's climate models.6
Why Restoring Carbon to Soils Is So Important
Much of the focus on reducing greenhouse gases revolves around
reducing carbon emissions, but now that we’re armed with rapidly
expanding knowledge about carbon storage in soils, greater attention
should be paid to carbon sequestration and
soil restoration.
Carbon sequestration refers to taking the carbon from the
atmosphere and putting it back into the soil, in a stable form of
organic matter.
Many scientists say that regenerative agricultural practices can
turn back the carbon clock, reducing atmospheric CO2 while also
boosting soil productivity and increasing its resilience to floods,
pests, and drought. Today, just three percent of North America’s
tallgrass
prairie remains, resulting in a massive loss of soil carbon into
the atmosphere.
According to Yale:7
“The importance of soil carbon—how it is leached from the
earth and how that process can be reversed—is the subject of
intensifying scientific investigation, with important
implications for the effort to slow the rapid rise of carbon
dioxide in the atmosphere.
Scientists say that more carbon resides in soil than in
the atmosphere and all plant life combined; there are 2,500
billion tons of carbon in soil, compared with 800 billion tons
in the atmosphere and 560 billion tons in plant and animal life.
And compared to many proposed geoengineering fixes,
storing carbon in soil is simple: It’s a matter of returning
carbon where it belongs.”
According to Rattan Lal, director of Ohio State University’s
Carbon Management and Sequestration Center:8
“The top priorities are restoring degraded and eroded
lands, as well as avoiding deforestation and the farming of
peatlands, which are a major reservoir of carbon and are easily
decomposed upon drainage and cultivation...Bringing carbon back
into soils has to be done not only to offset fossil fuels, but
also to feed our growing global population. We cannot feed
people if soil is degraded.”
Soil’s Favorite Food: Humus
Several game-changing farmers are addressing this problem.
California farmer John Wick, who calls himself a “carbon farmer,” is
making humus compost. Wick is the co-founder of the Main Carbon
Project in Nicasio, California. Carbon-rich organic matter is what
gives
soil its water-retention capacity, its structure and fertility,
so the objective is to add high-quality, sustainable organic matter
back into the soil—and humus compost fits the bill. Wick makes humus
compost from biomass such as corn stalks, wheat, and oat straw,
soybean stubble, manure, and clay, plus three microbial inoculants.
This is not ordinary compost, but closer to the naturally occurring
humus that forms on forest floors.
Humus and Compost Are Two Different Things
It’s important to realize that
compost and humus are different. Compost is organic matter
that’s been decomposing to the smallest particles. Finished compost
is only halfway to humus, which is a more effective and matured form
of carbon. Humus is not a layer of soil but a component in
soil—there is no such thing as a “humus layer.” Even though
commercial products are sold as humus, the vast majority is really
only finished compost, as true humus is only formed in nature.9
This is presumably why John Wick calls his product “humus compost,”
which is as close as we can get to true humus.
Through photosynthesis, a plant draws carbon out of the air to
form carbon compounds. What the plant doesn’t need for growth is
exuded through its roots to feed soil organisms. Over time, these
organisms (mostly bacteria and
fungi) break down organic matter into smaller and smaller
molecules until most of the usable chemicals in the organic matter
have been extracted by the microorganisms and made available to the
plants.
When all of the “good stuff “ is used up, the remaining material
is called humus in a process is known as humification. Humus
consists mostly of carbon in complex molecules or aggregates, and
because microorganisms cannot further decompose it, it’s extremely
stable—humus can persist in soil for hundreds and even thousands of
years. This is in contrast to "active" topsoil carbon, which is in
continual flux between microbial hosts and the atmosphere.
Humus Gives Soil Its Ability to Store Water and Nutrients
Scientists don’t yet fully understand humus, but they’ve been
able to identify some of the characteristics that make it so highly
beneficial, including the following:
- Like a big sponge, humus can hold up to 90 percent of its
weight in
water
- Because of its negative charge, many
plant nutrients stick to humus (nitrogen, calcium,
magnesium, phosphorus, and others), preventing them from washing
away and acting as nature’s slow release fertilizer
- Humus massively improves soil’s structure, making it loose
and friable and helping plants root by providing them better
access to nutrients, water, and oxygen
- Humus may help “filter” toxic chemicals out of the soil,
much like carbon-based water filtration systems filter toxins
out of your water
You can build your soil’s humus content by top coating—not
tilling—your soil with organic matter, such as woodchips, manure,
and compost. Tilling should be avoided as it destroys soil’s
intricate structure. Many innovative farmers and agricultural
scientists have found ways to turn animal and human waste into fully
finished, healthy compost—you can’t get much more sustainable than
that! And it really packs a punch—in one case, a farmer who topped
his soil one time only with one-half inch of manure compost
got 25 to 50 percent more plant growth for four years.
Turning Chicken Poop into Biochar
Biochar is another way to add stable, long-lasting carbon to
your soil. Biochar is created by slowly heating a biomass in a
low-oxygen environment, such as a kiln, until everything but the
carbon is burned off, and then putting it into the ground.
Historically, fire has been the driving force of the earth’s carbon
cycle. Natural fires started by lightning burned large swaths of
plants and trees, returning the carbon back to the soil in the form
of charcoal. Today, most societies take steps to prevent wild fires
and greatly restrict burning practices.
Midwest poultry farmer Josh Frye has figured out a way to do what
fires do, by transforming chicken poop into biochar using green
technology with minimal emissions. Just like the scientists who
successfully turned
human urine into fertilizer, this is one more example of how
waste can be turned into a useful and sustainable product with the
potential for improving our food system and reducing environmental
impacts.
Increase Your Soil’s Health with Woodchips
A great, cost-effective alternative to compost or biochar that
will radically improve the nutrient quality of your foods is
mulching with wood chips. I learned about
wood chips during my interview with Paul Gautschi. You just lay
down uncomposted wood chips on top of your garden—using whatever is
available locally, typically a combination of leaves, twigs, and
branches. The chips break down gradually and are digested and
redigested by a wide variety of bacteria, fungi, and nematodes in
the soil, which is exactly what happens in nature.
After a year or so, you’ll develop lush soil underneath the chips
that will happily support trees, vegetables, or whatever else you’re
trying to grow. The longer you leave the chips on and the deeper you
heap them, the thicker your topsoil will be. Wood chips also reduce
your weeding by more than 90 percent, because the weeds that do grow
are very easy to pull out by their roots. Wood chips drastically
reduce the need for watering and eliminate your need for
fertilizers, and they provide excellent insulation for your plants
and soil, moderating the temperatures in both summer and winter.
Woodchips are a very concentrated form of biomass and can form
massive amounts of humus if allowed to compost properly. I have
personally put on over a half a million pounds of woodchips on my
quarter acre of landscaping and am starting to see excellent results
on my four dozen fruit trees, berry shrubs, and vegetables. The
chips eliminate the need for irrigation and fertilizers, reduce
weeds, and serve as earthworm magnets. The earthworm population on
my property has literally exploded.
You Can’t Be Healthy Without Food from Healthy Soil
One of the more insidious aspects of the industrial food system
is that, as soil becomes sicker and less able to perform its
functions, farmers become increasingly dependent on the chemical
technology industry—they become trapped. The use of
glyphosate begins a downward spiral, making it necessary for
farmers to use more and more herbicides, pesticides, and synthetic
fertilizers that kill soil microbes. Especially if they’re using
genetically engineered (GE) seeds. Weeds become resistant to
glyphosate, so farmers must use more weed killers.
Crops become nutrient-deprived, so they’re forced to increase
their use of synthetic fertilizers. Weeds and bugs become superweeds
and superbugs... and on and on in a vicious cycle. The best way to
avoid this trap is to refrain from using agrochemicals in the first
place. Any organic farmer will tell you that they’re growing SOIL,
not food—a properly cared for soil will take care of growing your
food. The key is to use regenerative soil techniques instead of
factory farming approaches, which are degenerative.
The answer to world hunger is not GE foods or fuels, but rather
reverting to ecologically rational and
sustainable agricultural practices, with an emphasis on
supporting small local farmers. In a comprehensive global report
entitled “Agriculture at a Crossroads,” IAAST (International
Assessment of Agricultural Knowledge, Science and Technology for
Development) gave high-tech farming a dismal two thumbs-down.10,11
Resistance to revamping the food system can be expected from a few
mega-corporations whose pockets are lined by the chemical technology
and pesticide industries, but as a consumer, you have a great deal
of power as you vote every day with your wallet.
Copyright 1997- 2015 Dr. Joseph Mercola. All Rights Reserved.
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