The Role Microbes Play in Increasing Soil Fertility

soil fertility

The microbial population or microbial biomass (MB) reflects soil fertility. For over 2 million years, plants and soil microbes have worked together to create what we call fertile “soil”.

How do they work together? The plant supplies the microbes with carbon rich food. The microbes then mine the soil for the required minerals. Microbes can actually manufacture nitrogen and antibiotics that protect the plant from pathogens in return creating carbon stores that build soil structure and sequester carbon.

Like all good partners, what is good for one is good for the other, i.e., a healthy MB predicts a healthy plant. Therefore, supplying NPK directly to plants disrupts the plant microbe relationship – plants no longer feed the microbes and the MB decreases accordingly. Soils with low MB suffer from erosion, compaction, and poor structure. Sadly, this is how we have lost 50% of the earth’s soil.

Soil microbes, like all living things, need food. They need to be fed carbon and nitrogen from plants or organic matter so they can mine the minerals, P, K, Mg, Cu S etc. from the soil. If there is not enough of any nutrient, including the minerals that should be in the soil, it negatively affects the number of microbes; just as humans do not thrive when we are deficient in a critical nutrient.

Oxygen, water, and an agreeable pH and temperature are also important for soil microbes. Compacted soil is low in oxygen and microbial biomass. As soil dries, microbes die or become dormant. MB is much lower in low and high pH soils than in those that are in the neutral range. This is because most enzymes work best at neutral pH and all metabolism is enzyme dependent. MB also contracts during intense cold and heat. Plant roots require these same conditions

Microbes also need shelter to survive. Soil aggregates provide small cubbyholes that accommodate oxygen and water. It is in these areas where microbes attach themselves to be protected from predators. These predators are larger than they are; think of how little fish hide in coral. Not only are soil aggregates homes for microbes, they are homes built by microbes. The capsular material that microbes secrete to attach themselves to soil particles is long lasting. It binds the soil particles, therefore, creating aggregates that build soil structure and prevent erosion. These aggregates provide the water, oxygen and wiggle room needed by plant roots.

Furthermore, soil microbes build up carbon in the soil by producing humic matter. When microbes die, their bodies become stored carbon. This is good for microbes in the way that a savings account is good us. It is important for the soil as well because the humic matter increases soil structure. This allows more oxygen and water storage. It is also a resource that microbes can take a loan from before harvest when plant material is not being released to microbes. For too long we have relied on microbes borrowing from this humic carbon source and have released ½ of the soils stored carbon to the air as carbon dioxide. This has contributed to climate change and loss of 50% of earth’s soil. Microbes have always worked well with plants to create soil and they can help us restore exhausted soils back to fertility.

microBIOMETER® educating farmers in the Gulf Region on the importance of life in the soil.

Sustainable Organic Q8 was launched in mid-2018, educating people on recycling their organic waste, being environmentally aware and teaching people how to grow whatever and wherever they can. As far as gardening/farming styles, Sustainable Organic focuses on the value of the living soil and the soil food web and teaching home gardeners and farmers to slowly shift the general culture from MONOCULTURE, “Babysitting plants” and providing all their needs from nutrients to medicine to DIVERSITY, Building and regenerating an ecosystem that will take care of itself or at least be a bit less exhaustive and much more sustainable.

Sustainable Organic has helped bring diversity above grounds back to the region in the past couple years. However, many people are still very new to the life underground and living soil. Their gardening/farming practices rely heavily on providing nutrients and immunity/medicine to plants. To them it is cheap, it works, and they’re so set in their ways that the idea of change is becomes a source of anxiety.

Although more and more gardeners are praising the life in the soil, they also practice routine solarization and refuse to refrain from it, reflecting their hazy understanding of soil biology and the soil food web and what it really takes to construct. Testing the soil to most growers means checking nutrient availability, water content and pH.

For the sake of adding some objectivity to soil biomass and increasing the value of soil biomass testing, Sustainable Organic sent microBIOMETER® test kits to popular gardeners in Kuwait, Saudi and Dubai to experiment with by testing their soils and compost. These gardeners have a large number of followers and they educate via social media, gardening courses, and workshops. By starting to broadcast microBIOMETER® as a means of testing the biomass in the soil and amending it based on the readings received, Sustainable Organic intends to create a trend in the region shifting the focus more on the life in the soil than the mineral content.

“microBIOMETER® is an innovation that has made it possible to quantify the life in the soil. This economic tool, I believe, not only helps us improve our soil at the gardening/farming level, but it can also help us deepen our understanding and comprehension of the soil food web and the LIFE underground. This will ultimately lead to a tremendous positive change at the psychological and behavioral level.  It’s common to see people in our region praising the life in the soil (finally), but then professing solarization at the end of or the beginning of a grow season. This is an obvious clash in concepts that we hope are not deeply understood. We believe with popularizing the use of the microBIOMETER®, we can help clear the fog!

It’s beautiful to see people go out in the middle of the desert and start digging holes to “build” soil, plant trees and mulch around them; then announce seeing mushrooms and biologic diversity; start talking about soil biology, arbuscular fungi and carbon sequestration and tell farmers near them to try out the living soil method learned from Sustainable Organic. They say think globally and act locally. We intend to revive the desert in the Arabian Peninsula with Mother Earth and her fever at heart!”

About Dr. Jassem Bastaki. Originally from Kuwait, Jassem acquired his education in Head and Neck Endocrine Pathology in Pittsburgh, PA. In 2012, he left Pittsburgh to practice diagnostics and oncology in Kuwait and in doing so transitioned from fertile land to urban settings in some of the harshest climates in the world. The stress from his line of work led him back to gardening; indoors and hydroponic initially until he learned how to garden outdoors no matter the climate or conditions. Every second he spent with his plants taught him more and more about life and the reality we are unaware of. “We are guests on this earth with everything else that lives on it and in it.” The more he realized what was missing and where to find it, he wanted to help everyone find their way back to earth.

Jassem is a microBIOMETER® distributor in the Gulf Region as well as Iraq, Jordan and Egypt.

microBIOMETER® at Penn State University.

Left: “Intensive” section. Right: “Extensive” section

We began offering microBIOMETER® Academia Classroom Kits  last year and are excited with the interest we have received so far from universities, high schools and other academic institutions in the U.S. and abroad. Professors are utilizing our soil test to introduce their students to the world of microbes and soil health.

Mary Ann Bruns, Professor of Soil Microbiology at Penn State University  recently shared how students in her Soil Ecology class used microBIOMETER® to analyze microbial biomass in the 10-year-old Green Roof Medium of the Forest Resources Building on campus.

Students took composite samples from the “intensive” section (where rooting medium was originally 12 inches in depth) and the adjacent “extensive” section (depth of 4 inches). Samples were taken next to the blue fescue plants in both sections.

Having a deeper layer of growth medium provides more water and nutrients for plants, so the hypothesis was that samples from intensive (healthier) areas would have higher MBC than those from extensive (dried out) areas. Average depths were 7.1 and 3.8 inches, respectively, in intensive and extensive areas. Average MBC for the two areas were 253 and 159 micrograms per gram medium, respectively. Click here to read the full report.

A special thank you to Mary Ann and her students for sharing their research, data and photos! If you would like to share your student’s microBIOMETER® research in our newsletter or learn more about our Academia Classroom Kits, please contact us.

From left to right: Penn State students Tyler Gryskevicz, Amanda Grube and Jason Ben Legayada.

Carbon Sequestration

Increasing your soil microbes increases carbon sequestration. Carbon is stored in the soil as “humic materials” i.e. C,N,P,K etc.; rich organic matter which is the soil organic carbon or sequestered carbon in the soil. ­­­­­

The formation of humus, the final stable carbon, is a stepwise process. All organic carbon in soil comes from plants, either directly or via digested plant material. It starts with plant material being digested by soil microbes, or in the case of brown manure, being predigested by animals and further digested by microbes. The breakdown process begins with soil fungi and bacteria. As these microbes are fed carbon, they multiply. If fresh carbon stores are not utilized, they become attached to soil particles and become stored, therefore, less available as food sources. As microbes die, if they are not immediately cannibalized, their remains also become part of the more recalcitrant humic material.

Slowly, this humic material, which is as much as 80% the bodies of dead microbes, builds up. We measure it as soil organic carbon (SOC) and it reflects the carbon sequestered in the soil, but it also contains all the minerals and other plant nutrients. To increase SOC, the fresh organic matter required to feed the microbes and in turn the plant via the microbes, there needs to be an excess of the minimum required for a low microbial population. If there is an excess, the microbial population increases, and their dead bodies will increase the humic matter, in return increasing carbon sequestration. If it is not adequate, the soil microbes will be stimulated by the plant to mine the stored organic matter, which will decrease the stored carbon. It is not surprising that scientists have compared the plant/microbe/soil fertility index to economic models. A rich soil, like a rich man, has money in his pocket and money in the bank, for soil the currency is carbon.

This system is very much like our agricultural complex. There is fresh food, which we utilize within days, food we freeze or can, which requires freezers and can openers to access, and food stores (our sequestered carbon) that we maintain in silos as protection against disaster.

Soil research using microBIOMETER®

In the spring and early summer of 2020, the Nutrient Management Spear Program at Cornell University conducted a soil survey of yield-stability based management zones on a New York dairy farm.

Ben Lehman, research assistant in the Nutrient Management Spear Program at Cornell University, completed a study on the Within- Field Variability of Soil Characteristics and Corn Yield Stability on a New York Dairy Farm.

Ben utilized microBIOMETER® in his research to determine the microbial biomass of the soil samples.

This study was presented at the 2020 American Society of Agronomy Annual Meeting.

Source: Cornell Center for Materials Research

microBIOMETER® assisting farmers with regenerative agriculture around the world.

Sometimes the wisdom we need to build a great future is buried in the past. Regenerative agriculture isn’t an entirely new concept, it’s actually more of a return to the wisdom of farmers from days gone by. What’s old is new again and its popularity is spreading around the globe like a prairie fire.

While regenerative agriculture gives a well-earned nod to the past, its relationship with science and technology allows it to effectively transform the way we currently grow food. microBIOMETER®, with their customers all around the world, are leading the way with technology that shows farmers when their soil health practices are working and when they are not.

“I believe biological agriculture is the way to regenerate and create more resilient soil that will supply nutrients and higher immunity to the plants. This is why microBIOMETER® has become an invaluable asset to my soil management efforts.” ~ Marcelo Chiappetta of Chiapeta Empresa Agricola in Rio Grande do Sul, Brazil.

Creating healthy soil may take the wisdom of generations of farmers, but microBIOMETER® supplies the knowledge farmers need to best manage potential outcomes.

Variance in soil samples explained

Often, we are asked about variance – different results when you test the same sample. Our answer is that nature produces most of this variance. To explain, when you measure out 0.5 cc of soil, you have on average about 0.6 grams of soil. If your microBIOMETER® results read 300ugMBC/gram of soil, that means you have 600ug of microbial biomass – we divide the number we get by ½ because the literature tells us that 50% of the dried MB is carbon. As dried bacteria is estimated to weigh 1pg, if this were all bacteria, it constitutes 600,000,000pg or 600 million bacteria.

Now imagine that I have 600 apartment buildings in NYC that each contain 1 million people, and I decide to check 10 apartments in 10 buildings at 4 p.m. to estimate the number of people actually in the building. Obviously, it would vary because people are not always in their apartment and different apartments have different numbers of inhabitants – the same is true for soil.

Soil contains microscopic aggregates of different sizes and the number and type of inhabitants in each varies on the physical and chemical composition of the space as well as the nutrient, pH and hydration level. Each sample you take is like looking at a number of different apartments in a number of apartment buildings.

For this reason, when conducting research, soil and medical researchers run duplicates or triplicates. Because of cost, soil labs generally do not run duplicates and they see 10- 25% variation. We are recommending running duplicates when using microBIOMETER® unless you are doing academic research. Generally, we see <10% variation for a given sample, and for a field that looks homogeneous. Pastures can have much higher variation because the nutrients level across the area varies tremendously.

How do plants farm soil microbes?

Source: How Plants ‘Farm’ Soil Microbes and Endophytes in Roots

UPDATE: Dr. White sat down with Dr. Fitzpatrick and Jeff Lowenfels to discuss rhizophagy. Click here to view the webinar. (Jan. 15, 2021)

A summary of James F. White’s presentation at BioFarm, 2020 (Nov. 12, 2020). 

The rhizophagy cycle is an amazing process recently discovered by James White’s laboratory at the University of New Jersey, by which root tips “ingest” bacteria and absorb nitrogen and phosphorus and other nutrients from them.

The microbes pictured here in roots are called endophytes because they can live inside plants. The bacteria are attracted to the root tip by root exudates. They then enter the root where the cell walls are dissolved using superoxide, allowing nutrients to leak out to the plant. But the plant does not kill the microbes instead the microbes stimulate the formation of root hairs, which are escape routes for the microbes.

After ejection from root hair tips, bacterial cell walls re-form. The bacteria fatten up and are soon ready to acquire soil nutrients and become another meal for the plant.

Source: How Plants ‘Farm’ Soil Microbes and Endophytes in Roots

Not only does rhizophagy provide mineral nutrients, it is also the stimulus for formation of root hairs, which are critical to the establishment of a healthy root as can be seen in this photo of a plant root with and without endophytes.

 

 

 

How much carbon can be stored by increasing your soil microbes?

microBIOMETER® reports the microbial biomass as ug of microbial carbon/gram of soil. The chart pictured here shows how much carbon can be stored in an acre just by increasing microbial biomass alone. (Chemically fertilized farmland averages about 100 ug/microbial C/g of soil.)

Microbial biomass is the best single estimate of soil quality. It is the bodies of dead microbes that build humus/soil organic carbon, returning carbon to the soil and building soil structure which prevents erosion and pollutant run off. (Chemical nitrogen fertilizers have been shown to inhibit microbial biomass.)

The literature reports that lab measurements of soil organic carbon are not sufficiently accurate in monitoring an increase in carbon sequestration in less than 3 years but that a yearly increase in microbial biomass can indicate that the process of carbon accumulation is occurring.

microBIOMETER® has been used to demonstrate increases in soil carbon due to increases in microbial biomass on the Apple campus in Texas and for 3 years by the NYC Arts and Science Carbon Sponge Project.

Source: Direct evidence for microbial-derived soil organic matter formation and its ecophysiological controls.

Research shows microBIOMETER® correlates with crop health

Katharhy G. is an agroecosystem and ethnoscience researcher who traveled to Ecuador to investigate the relationship between microbial biomass and crop health, as well as to study the local indigenous agriculture practices.

He visited 28 different farms growing 15 different crops. 14 of these farms are practicing conventional farming, while the other 14 farms are practicing indigenous regenerative farming. Most sites are not receiving irrigation. He tested the soil with microBIOMETER® and ranked the crop health as poor (1), average (2), good (3), excellent (4).

As the graph shows, microbial biomass correlated with crop health under all these different conditions. Samples with microbial biomass lower than 225 were all poor (1) and samples above 400 were all excellent.

The take home lesson is that to improve your plant health and yield, increase your microbial biomass by feeding your microbes with organic amendments.

If you have microBIOMETER® research data you’d like to share with us, please contact us. We would love to share it with our readers!

Contact:. katharhyg@gmail.com