Seasonal dynamics are a major driver of soil microbial communities. Much like you and I, microbes are more active during some seasons, and more dormant during others. This can be attributed to the different responses microbes have to nutrient inputs, climatic conditions, and other soil properties. As there are a lot of factors that affect microbial activity, it can be difficult for farmers or researchers to make definitive statements regarding the relationship between their soil microbial communities and seasonal changes. Specifically, temperature, moisture content, and the existence of plant life are considered the most important factors affecting microbial growth and activity within a season. 

The presence of plants on the soil has a large impact on microbial life. As plants form, they begin to cultivate microbes surrounding their roots by producing nutrients for the microbes to essentially feed on. As the microbial community grows, they undergo a series of processes allowing them to obtain nitrogen and mineral nutrients from the soil and then provide the nutrients back to the plant to stimulate growth. This is part of the symbiotic relationship between plants and microbes– they support each other through the mining of nutrients from the soil and sun. 

Just like plant presence, temperature greatly influences soil microbial properties. During cold seasons, temperature is considered a major limiting factor of microbial activity, whereas water availability could be a limiting factor during the summer season. Soil temperature can affect organic matter decomposition and mineralization rates, thereby impacting microbial biomass and activity levels. Bare soil, or soil without any plants growing, will have lower microbial activity occurring, regardless of season. This is why researchers and land stewards have emphasized the planting of cover crops between growing seasons in regenerative agriculture– as cover crops can alter soil properties and increase the biomass and diversity of microbial communities. In the warmer or hotter seasons, the addition of cover crops can also help to mitigate how much heat the soil is absorbing.

Studies show that microbial activity in agricultural soils increases in the fall when compared to other growing seasons–likely due to an increased level of nutrients and soil organic matter from crop and plant residue post harvest. Throughout the wintertime, or non growing season, microbial activity and composition is thought to be stagnant, but stable. An increase in microbial activity is said to occur after the thawing of frozen soils and can be linked to the freeze-thaw cycle (FTC) that colder climates experience. As snow freezes over soil, it inhibits air diffusion from occurring, creating anaerobic conditions for the microbial communities and therefore altering the soil community structure. In turn, this causes an increase in denitrification, respiration, and production of greenhouse gases, which are being trapped under the frozen layer. Once temperatures begin to rise, the soil begins to thaw, allowing oxygen into the soil. This provides labile carbon and other nutrients to the soil, which increases microbial activity and biomass. However, once thawing occurs, those greenhouse gases that were once trapped, are released into the air. This exact dynamic between microbial activity and the FTC is still being debated due to different soil properties greatly affecting freeze/thaw rates and as researchers use different methodologies, making it difficult to compare results between studies. 

But despite the controversy surrounding the exact relationship between microbes and seasonal temperature changes, researchers do agree that microbial biomass and activity are related to seasonal temperature fluctuations. They’ve found that generally, microbial biomass decreases once the temperature increases past a certain point. As temperature increases, there is also an increase in CO2 being released from the soil, which we refer to as respiration. So when more respiration occurs, more carbon is being put into the air. This respiration process is sensitive to temperature change, which is why it’s imperative to have a better understanding of the seasonal dynamics of microbial communities. 

As soil microbial life varies naturally by season, it might be hard to differentiate the natural seasonal changes from the changes related to your regenerative growing practices. Understanding the short term seasonal dynamics of microbial communities in various soil conditions is key in furthering our understanding of soil biology. Documenting and analyzing periodic readings with microBIOMETER® can assist you in differentiating between natural and seasonal changes in your soil.

References:

Bates, Todd B. (2018, Oct 10). How Plants Harness Microbes to Get Nutrients. Rutgers.edu.
       https://www.rutgers.edu/news/how-plants-harness-microbes-get-nutrients

Bizzell, E. (2018, April 16). Plants and the bacteria at the root of it all. ASM.org.
        https://asm.org/Articles/2018/April/plants-and-the-bacteria-at-the-root-of-it-all

Gao H, Tian G, Khashi u Rahman M and Wu F (2022) Cover Crop Species Composition Alters the
       Soil Bacterial Community in a Continuous Pepper Cropping System. Frontier Microbiology12:789034.

Jensen G, Krogstad K, Rezanezhad F and Hug LA (2022) Microbial Community Compositional
       Stability in Agricultural Soils During Freeze-Thaw and Fertilizer Stress. Frontier Environmental Science. 10:908568.

McDaniel, M. D. and Grandy, A. S.: Soil microbial biomass and function are altered by 12 years of
        crop rotation, SOIL, 2, 583–599, (2016).

onwuka B, Mang B. (2018) Effects of soil temperature on some soil properties and plant growth.
       Adv Plants Agric Res. 8(1):34-37

Pietikäinen, J., Pettersson, M., & Bååth, E. (2005). Comparison of temperature effects on soil 
       respiration and bacterial and fungal growth rates. FEMS Microbiology Ecology, 52(1), 49–58. 

Simon, E., Canarini, A., Martin, V. et al. Microbial growth and carbon use efficiency show seasonal
       responses in a multifactorial climate change experiment. Communicati

An interview with the San Antonio Food Bank who is using microBIOMETER® in their Farm and Garden Program.

How are you using microBIOMETER®?

We are using microBIOMETER to track the soil health on our farms, gardens and compost. This test allows us to understand if we are providing an environment for our crops to thrive. Because we grow fruit trees, herbs and annual edible crops the fungal to bacterial ratio helps us identify the current soil health and help us understand what strategies we can look to implement to improve that environment over time.

How does microBIOMETER® help people understand the importance of soil biology as opposed to the historical focus on soil chemistry?

Traditional soil tests give you a window into what nutrients are or are not available within your soil. It can give you insight into how much organic matter might be present in your soil, but not how you might work to track progress on soil health, diversity or improving your soil food web on an affordable level. While knowing the nutrient breakdown is helpful information it does not help you understand if you are providing an ideal environment for those micro and macro organisms to thrive and ultimately aid your crops or plants in receiving those nutrients and so much more. The microBIOMETER® test kit has helped us better understand our complex food web and what strategies we can do to create a more balanced environment for our crops and our soil.

How did the microBIOMETER® information assist you with your project?

This test helps us to educate not only our staff on soil health strategies, but also our volunteers and anyone who attends are Teaching Garden classes. The data we collect helps us to showcase how the strategies we are employing to improve our soil health are making a difference from season to season as opposed to every two years from a traditional soil test. That enables us to make better recommendations to our community of growers about ways they can improve their soil, too.

About the San Antonio Food Bank

The San Antonio Food Bank takes pride in fighting hunger, feeding hope in our 29-county service area. We believe that no child should go to bed hungry, adults should not have to choose between a hot meal and utilities, nor a senior sacrifice medical care for the sake of a meal.

Founded in 1980, The San Antonio Food Bank has quickly grown to serve 90,000 individuals a week in one of the largest service areas in Texas. Our focus is for clients to have food for today but to also have the resources to be self-sufficient in the future.

Fighting hunger is our number one priority but we also serve to educate and provide assistance in many other ways. We achieve this through our variety of programs and resources available to families, individuals, seniors, children, and military members in need.

Our Farm and Garden Program consists of two locations and six growing spaces, including two farms and the garden at the New Braunfels Food Bank. Together these areas total more than 100 acres and provide 300,000 pounds of fresh local produce annually to our 29-county service area. We utilize 5,000 volunteers annually to assist with our operation and to provide local produce to the community.

Our Farm and Garden Program strives to provide quality, local produce to the community and to provide resources to teach those in our community how to grow food for today and in the future. In order to meet those goals, we start with our soil. By understanding our soil biology and health we get a window into what is happening at the root level and better understand the environment where our crops live and how to make improvements so we are growing healthy plants and nutritious crops. We believe everyone deserves access to nutritious fruits and vegetables.

Our Teaching Garden classes provide information about the importance of soil and composting as a foundation for building soil diversity and health. We utilize cover cropping on the farms and in our gardens to reduce erosion, build soil fertility, reduce weed pressure and increase organic matter. We create and utilize composting to increase the diversity of our soil, divert valuable resources from the landfill and introduce the community to the benefits of composting at home or in the community.

Informal science education is a key for community engagement and healthy gardening. Community gardening  brings numerous benefits such as fresh produce, therapy, physical exercise, reduction in grocery bills, improvement of mood among many others.

“Last weekend I had the privilege to teach community gardeners on the importance of soil testing side by side with my very first student at NYBG Adult Education program (class 2015). Dr. Joan Basile is a clinical psychologist who has developed her own horticulture therapy program incorporating soil knowledge brining therapy & soil science & gardening together.” – Dr. Anna Paltseva,  soil_expert.

“While the microBIOMETER® results showed there is room for improvement, the result from last year’s beds also proved that composting and mulching practices are paying off in increased soil life. This means that sandy soil will gradually be able to hold nutrients better and better!” – Dr. Basile

The Biospheres, working through the CDA*,  accompanies and trains farmers/agricultural companies in the agroecological transition based on a soil conservation approach. The group is also working on applied research projects and therefore on trials under real farming conditions in which they evaluate the impact of certain changes in practices on different indicators (biological, chemical, physical, economic).

“One of our primary objectives is that farmers succeed in putting biology back into their soils to ensure their natural fertility. We are therefore very interested in everything that lives in the soil, from earthworms and microarthropods to microorganisms (bacteria, fungi, nematodes). For us, microbial biomass is one of the most important indicators that help us understand soil biology. Fungal to bacterial ratio, which is a less documented indicator for the moment, remains interesting to observe in certain situations and is the object of real research by our R&D team to understand how best to interpret it.

We have been using microBIOMETER® for 8 months now to test the soil in different projects in our panel of biological indicators. microBIOMETER® provides us with quick and easy results on microbial biomass and F:B ratio which is a real plus for us. We can perform tests directly in the field and present the results to the farmers. Moreover, the affordable price of the analysis allows us to perform soil biology tests in projects where we had no affordable way to do so before.”

*CDA, Centre de Développement de l’Agroécologie, are affiliates dedicated to R&D and advisory.

 

 

soil microbe testing

Ariel White; Post-Wildfire Forest Reboot Kit

Ariel White, a ninth grader at Pretty River Academy in Ontario, Canada, utilized microBIOMETER® in their science fair project titled Post Wildfire Forest Reboot Kit.

The project was awarded first place at their high school and chosen to compete at the Simcoe County Regional Science Fair. At the regional fair, Ariel was awarded a gold medal, Best of Earth and Environmental Sciences, Best of Fair, The Dufferin Simcoe Land Stewardship Network Award, and was one of seven students selected to represent their county in the Canada Wide Science Fair where they won a silver medal!

About the project: Forest fires have increased due to climate change, causing forests to burn down at an unbelievable rate. Now we need forests more than ever, yet they have been taking years if at all to regrow. This project explores the question “how can we boost the speed of forest regrowth after forest fires?”. For phase one of this experiment, each plant was graded for performance using tests such as success-rate, growth-rate, compost-value, and self-propagation. For the second phase, it was seen what effect this plant had on the soil microbiome; which is key to healthy, speedy plant growth and isn’t evident after fires. It was concluded that the morning glory substantially increased the microbiome health from inevident to healthy, and had an almost perfect performance score. These results are very important to our world’s future as they could help to deter climate change and repair our forests and their diverse ecosystems.

soil testing carbon

Soil testing

Modern agriculture practices have led to the systematic degradation of the world’s soil and release of carbon into the environment. The effects are increased need for expensive and environmentally dangerous inputs (fertilizers, pesticides, and herbicides), the loss of fertile top soil, decrease in water holding capacity of soil and dangerously high levels of atmospheric carbon.

Farmers, industry, and environmentalists are looking for cost-effective and reliable ways to measure soil health, to assess impacts of progressive changes on soil and harvest management, and to measure carbon in soil. Before microBIOMETER®, growers have traditionally relied on expensive lab testing of soil. Many current methods are technique and individual lab dependent. Therefore, run-to-run and lab-to-lab variation can greatly affect consistency leading to increased variability. Current methods are performed in labs and the soil is aged and changed from the time of collection. Furthermore, lab tests are difficult to use in developing countries as they can cost upwards of $500 per sample. This makes the test prohibitive to some markets and limits the number of times a grower can test their soil.

Our mission at Prolific Earth Sciences is to enable soil stewards all over the world to use mobile technology and our low-cost soil test to assess regenerative soil practices, to improve soil health, and work towards increased soil carbon sequestration. microBIOMETER® equips growers with the data necessary to make decisions on which practices are the most cost-effective. Inputs such as fertilizers are expensive and changes to practice are risky. Monitoring soil microbial biomass inexpensively, in real time, can help a soil steward quickly assess if an input and practice is improving soil health and worth the investment. In other words, assess before you invest! We also envision microBIOMETER® one day being a powerful tool in the measurement and audit of carbon sequestration programs.

microBIOMETER® has been on the market for over 3 years with direct and distributor sales and currently has customers in over 20 countries.

Graham Mackie, Golf Course Manager at Edzell Golf Course in the U.K., has been using microBIOMETER® to monitor the health of the soil on the greens. Here is what he had to say about our soil test.

“I really like microBIOMETER®. It is simple to use and for the first time I can get baseline readings to see what is effective and what is not in influencing soil biology. As a golf course manager I believe that swinging the F: B ratio in favor of the fungi will allow the dominant grasses to be the desirable perennials.

I took microBIOMETER® readings of the main 18- hole course as well as the small 9-hole course and the readings correlated with what I expected. The 9-hole greens have more poa annua, therefore, were more bacterial dominant. I also took a reading of an area of untouched fescue rough which was very fungal dominant, as expected. It was great to have this theory confirmed. I am now looking forward to see if and how I can swing the balance to more fungal dominance on the greens.”

A BIG thank you to Graham for sharing his testing experience with us!

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.

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.

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.