The “Soil Food Web” Paradigm

Healthy soil is built and maintained by a universe of soil organisms. These organisms make up the soil food web and are the key to unlocking fertility in the soil. The soil food web forms the basis of a healthy farm ecosystem. Without them, farmers and gardeners are required to do the extra work of fertilization, pest/weed and disease control. It doesn’t need to be this way. Healthy soil and healthy plants can happen without our endless toil. But this all hinges on a sound understanding of “soil food web science.” Over time, healthy communities of life underground have been devastated as a result of annual tilling, compacted soil, mismanagement of organic matter, and relentless applications of chemical fertilizers and pesticides/herbicides/fungicides. Various farming practices such as no-till, cover cropping, and chemical-free organic farming are all effective ways to support the soil food web. Gardeners and landscapers can utilize similar strategies to promote the vitalizing force of the critters below. However, nothing has been demonstrated to be more effective and important than compost for establishing the vital, regenerative and chemical-free growing power of the soil food web.

From: USDA's "Soil Biology Primer"

From: USDA’s “Soil Biology Primer”

“Viewing the soil as a regenerative living system is one big kick in the pants for anyone who has been taught that NPK fertilization is more relevant than soil biology.” 
-Michael Phillips

“Soil food web” science includes the following components: Sun, water, air, plants and their roots, bacteria, fungi, protozoa, nematodes, micro and macro-arthropods, earthworms etc, humus (decomposed organic matter) and the mineral components of soil – sand, silt, and clay, as well as humans and their management decisions. The web starts with and is governed by plants, who use the energy of the sun to make carbon chains (photosynthesis); much of these carbon compounds are used as root exudates to attract and develop beneficial microbial communities in and around their root system. Exudates are simple sugars, proteins, and carbohydrates released by plant roots to feed and stimulate populations of beneficial microorganism. They do not feed pathogens. (Lowenfels and Lewis 23-24). Understand that the energy going into roots is not only used to build root structure for stability and fertility; in general, about half of a plant’s energy that goes into its roots is released as exudates (Kourik 10). Why do they do this? Because the energy they give away comes back to them many times over.

The strange reality is that while humans garden plants, plants garden microorganisms. They do this because of the crucial role microbes play in the nutrient cycle. Whereas humans are fed by plants, plants are fed by microorganisms. Microbiologists have found that the number of microorganisms in the rhizosphere – a zone immediately around the roots, extending out about a couple of millimeters – is far greater than in the surrounding soil (Ingham, “Living Soil” 2011). What’s more, studies on foliar dynamics have revealed that living leaves produce exudates through their phyllosphere that attract microbes just as roots do through the rhizosphere (Lowenfels and Lewis 25). All this “life” competes for the exudates in the rhizosphere and phyllosphere. At first glance it would seem like the microbes are the ones being fed, but if you look a little deeper things get much more interesting.

“Soil organic matter is the storehouse for the energy and nutrients used by plants and other organisms. Bacteria, fungi, and other soil dwellers transform and release nutrients from organic matter.”
-Dr. Elaine Ingham

Soil life creates soil structure and produces soil nutrients. The activities of its members bind soil particles together into microaggregates as they create air and water pores. The chemical and biological activity in the thin layer of moisture around aggregates convert nutrients into soluble forms that roots can absorb via ion exchange. Unlike applications of fertilizer, soil nutrients in living soil releases slowly over time; they are available when plants need them. As compost, mulch and other organic matter is added to the soil, their nutrients become immobilized in dead bodies and subsequently mineralized (made available to plants) through digestion or decay. The proximity of microbial action in the rhizosphere is what makes mineralized nutrients far more bioavailable than soluble fertilizer forms.

“There must always be a perfect balance between the process of growth and decay. The consequences of this condition are a living soil, abundant crops of good quality, and livestock which possess the bloom of good health”
– Sir Albert Howard

An increasing number of farmers, gardeners and scientists alike are adopting this new paradigm of “living soil.” It’s not like adopting a child or even a family. When you adopt the living soil paradigm you adopt an entire community; in reality, this shift in understanding is an acknowledgment of an entirely new world. It is changing people’s entire relationship with the process of farming, gardening, and scientific study. The time has come to reform our notions of superiority in the web of life. Nature is not an inanimate resource bank awaiting our plunder. It is an ever-evolving dance of mutuality, collaboration, and adaptation. Time has come to see ourselves as part of this dance, not separate from it. Our roles as participants are many. The integrity and health of the niches that we occupy are largely the result of our attitudes and approaches to management.

Citations

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To All Soil Professionals…

(Written by Jacob Krieger)

To all soil professionals,

That means the farmers first and foremost. The stewards of our soils.

There are plenty of silly facts about global warming that don’t change anyone’s mind. Especially in the mid-west. Whether CO2 changes the global temperature or not does not change the fact that we have raised the amount of it in the atmosphere. Two primary ways of raising the CO2 levels have been burning carbon based substances and removing or killing the natural “resources”, or the Earths biota.

We can see the cars and factories for ourselves. We can all see the lack of trees while perusing Google Earth. We can all see millions of acres of exposed soil through vast amounts of the year with a short drive. We pride ourselves at the coffee table on our tidy little barren soil beds being prepped and poisoned for next years synthetic crop. Yum, yum, down on the farm, home grown goodness, eh?

Here is a fact that soil professionals should know when preparing beds of soil.

Professor of Soil Science at Ohio State University Dr. Rattan Lal has calculated that 476 Gigatons (Gt) of carbon have been emitted from farmland soils due to inappropriate farming and grazing practices (Christine Jones, PhD, www.amazingcarbon.com). In contrast, 270 Gt have been emitted over the past 150 years of fossil fuel burning (Jones, www.amazingcarbon.com).

In their study, “Carbon Sequestration Potential Estimates with Changes in Land Use and Tillage Practices in Ohio, USA,” Zhengxi Tan and Rattan Lal explain that the conversion of natural ecosystems to those managed agriculturally can reduce the soil organic carbon pool by up to 50% in the top 20 cm of the soil and 25-30% in the top 100 cm depth after 30-50 years of cultivation (Tan, Lal, 2005).

It makes sense that more carbon comes out of the soil being tilled than the carbon released making and running the engine tilling it. For, fossil fuels are mostly buried and compressed landscapes of once living organisms. These fossil organisms are no different from the organisms in our soil still. Destroyed, they release the same kind of carbon that was put there by the same photosynthesis.

All exposed soil will lose this soil-organic-carbon. Inappropriate tillage expands the process exponentially. Today we have realized that inappropriate agriculture has successfully released the carbon of a 30 foot thick organism that once covered the entire Midwest, the topsoil and root system of the tall-grass prairies. Bare soil is potentially a more feasible culprit for global warming than even electricity.

What’s more disturbing is that we now farm fuel despite all the free sources of energy. (Yes, free energy. It’s here and being denied)
Farm soil and keep it covered. For better crops, better health, and a cooler planet. Soil is an organism that cannot be disconnected from the plants that it works with symbiotically. It is a single organism. Plants and soil both die when separated. Hence the need for chemical supplements that further the biological selection and destruction. Stop bare soil and start capturing CO2.

AGRICULTURE COULD BE USED TO BUILD SOIL at rates scientists once believed would take thousands of years.

It is being done in most 1st world countries and has been since the 1950’s. It is a shame we don’t take it seriously here. Carbon farming is a concept that pervades the planet aside from the American discussions. Proper grazing, rotation, soil conditioning, reestablishment of proper biology and biodiversity, and the end of monoculture could curb our global catastrophe in a growing season. No-till is a start, perennial poly-culture is a possible future, there are hundreds of solutions to start improving and expanding upon. Regenerating what we have destroyed is first on the to-do list avoiding the next dust bowl.

Row crops and CAFO’s are two ends of the same goat. Putting the cows back to pasture has fixed over 15,000 acres already by way of Darren Doherty Everyone should know this by now and realize it’s a scam. We are down to a few million farmers who bought out all their former cooperation by just playing the market by the rules. We are mostly farmed by contractors and satellites now. Monopoly is not about calories produced per acre. It is about control. It is extremely important for everyone to produce the same thing for the few to have power over the many.

Stop playing their game. Research regenerative agriculture and help improve it. Help revision. You be the scientist. You change the world. Any lawn or large acreage can be a part of the solution. And there are way more solutions than problems, but it starts with a mind change. Learn what science has discovered about soil in the last 25 years! Even in the last 3 years we have completely re-written the book on soil and how plants grow! Get on it SOIL PROFESSIONALS!

If farmers knew anything about the role they play today and what they can change tomorrow, the world would see a revolution by spring.