soilhealth – Washington State Soil Health Committee

Contrary Science; Cover Crop Mixtures, Monocultures, and Mechanisms

This post from Andrew McGuire of WSU is part of an ongoing scientific discussion about the relative effects of cover cropping and monoculture. This excellent summary of historic and ongoing research helps to bring us up to date on this complex, fascinating, and timely subject.

Excerpt from the article:

Soil diversity not linked to plant diversity

One last contrary finding. Another common belief is that a diverse mixture of plant species will drive greater diversity in the soil than a monoculture. This is often given as a reason to grow cover crop mixtures. Here again, we have a new analysis of the accumulated research investigating this mechanism. Zhou et al. (2020) analyzed 1235 experiments done around the world on the effects of what they call global change factors on soil microbial diversity. These change factors included land use change, such as occurs when a natural ecosystem is converted to agriculture, and nutrient fertilization. From this analysis they make several surprising conclusions.

First, most changes in the number of species (alpha diversity) can be explained by a change in pH. pH! It truly is the master variable in the soil. This is good news, as we can and often do manage soil pH.

Second, as they state it, “Conversion from highly diverse natural ecosystems to homogeneous agricultural monocultures has a positive effect on microbial alpha diversity.”

Read that again, a positive effect. The same goes for conversion to pasture.

What is more surprisingly contrary is that this implies, and the authors state this, that changes in soil microbial diversity (number of species) are NOT linked to changes in plant diversity. I know, heresy, but thus sayeth the science.

This does not mean that the conversion to agriculture is all positive. The microbial biomass is reduced, probably due to the change from perennial to annual plants and the associated decrease in carbon flow to the soil³. Agriculture also changes the structure of the microbial community. What these structural changes mean in the crazily complex soil is a difficult question to answer, but they may all not be beneficial with respect to the soil or the environment. This does, however, remove another purported reason of growing cover crop mixtures.

Read Andrew’s full article here:

Contrary Science; Cover Crop Mixtures,
Monocultures, and Mechanisms

Re-wilding to Improve Soil Health

We couldn’t wait to share this story of re-wilding an English dairy and crop farm, which was economically unsustainable. Letting nature take over has resulted in the return of hundreds of threatened and endangered species as well as enriching the heavy Sussex soils of dense clay. It is a success story worth sharing. One take-away is that thorny scrub can be left in corners and patches as beneficial habitat, as well as hedgerows being planted between fields and allowed to grow wild.

Tardigrades and Preserving Human Blood

While soil scientists study the role of the Tardigrade in the microbial communities that make up healthy soil, other scientists are looking at the resilience of the Tardigrade for other beneficial uses. A common and nearly indestructible soil organism, the Tardigrade or Water Bear, creates a sugar called “trehalose” which allows the tardigrade to survive without water, in a dehydrated state, for decades. Scientists are experimenting with trehalose as a preservative for human blood. They are extracting trehalose from tardigrades and other animals that produce it, such as brine shrimp. Experimental results so far indicate that by injecting trehalose into blood cells, the cells can survive dehydration at room temperature. If this proves to be effective, after human trials with the rehydrated blood, it will be possible to store human blood for pandemics, for medical use where refrigeration is not available, even for use by colonists on Mars.

Injecting bacteria into rice paddies could reduce methane by over 90%

A newly discovered bacteria shown to reduce greenhouse gas produced by rice fields by up to 93%

Researchers in Denmark and Germany have shown that adding a recently discovered bacteria, called a “cable bacteria,” to rice plantings in their test lab resulted in a 93% reduction in the release of methane gas. Today rice fields worldwide are responsible for over 11% of all methane, a greenhouse gas several times more potent than CO2. The cable bacteria, one centimeter long (which is big for a bacteria), is named for its ability to create an electrical current along its filaments which oxidates the sulfides that cause methane, creating sulfates in deeper soils. This causes a downward migration of sulfates, boosting sulfate density in soils that outcompetes methanogens, the bacteria that cause methane gas. Aboveground plant growth was not affected by adding cable bacteria in this experiment.

The current practice of adding sulfates (ammonium sulfate or gypsum) to reduce methane causes an unhealthy build-up of sulfates in topsoil. But with bacteria recycling sulfides into sulfates below the surface, this build-up is prevented. The production of methane gas was reduced by 93% in this study. Field trials will follow to test the results on a larger scale.

Photo Courtesy of Anthropocene Weekly Science Dispatch

Chemolithoautotrophs!

One possible way that subsurface microbes can combat climate change is by capturing carbon and converting it to limestone.

These microbes use chemicals from rock as an energy system to feed themselves far underground, in the absence of sunlight. In doing so, they can produce organic matter that fuels the growth of other organisms, they can convert CO2 to fuels and other chemicals, and they can enhance the efficiency of solar panels (“photon-to-fuel efficiency”).

At the Washington State Soil Health Committee, we wonder what relationship these microbes have to topsoil?

What do you think? What do you know?

Two Important Bills for the State of Washington and Soil Health

UPDATE: Both bills mentioned below passed the House and the Senate and were signed by Governor Jay Inslee of Washington State.

Two bills have made it past the Senate and House in the State of Washington. These bills show that the soil health campaign started by Roylene Comes at Night, Washington State Conservationist, in 2014 has real traction and a new and exciting life of its own. A very special shout-out to Gary Farrell, the benefactor of the original Soil Health Committee, without whom it would not have lived and breathed and made a multitude of successful grants that have provided the groundwork, literally, for a new Soil Health Movement in our state.

As co-chairs, Lynn Bahrych and Gary Farrell led a volunteer committee of producers, conservation district staff and supervisors, educators, and state and federal agency representatives to invest grant funds from the state Conservation Commission and the federal NRCS in dozens of innovative soil health practices across the state from 2015 until today. The results of those experiments will be published by the end of 2020 and so far have been truly remarkable, thanks to the hard work and inspiration of those receiving the grants. The successes and lessons learned during these five years will be passed along to the committee in its next home at the Washington State Conservation Commission.

First is SB 5947 – 2019-20 which establishes the sustainable farms and fields grant program.

“The legislature finds that Washington’s working agricultural lands are essential to the economic and social well-being of our rural communities and to the state’s overall environment and economy. The legislature further finds that different challenges and opportunities exist to expand the use of precision agriculture for different crops in the state by assisting farmers, ranchers, and aquaculturists to purchase equipment and receive technical assistance to reduce their operations’ carbon footprint while ensuring that crops and soils receive exactly what they need for optimum health and productivity. Moreover, the legislature finds that opportunities exist to enhance soil health through carbon farming and regenerative agriculture by increasing soil organic carbon levels while ensuring appropriate carbon to nitrogen ratios, and to store carbon in standing trees, seaweed, and other vegetation. Therefore, it is the intent of the legislature to provide cost sharing competitive grant opportunities to enable farmers and ranchers to adopt practices that increase appropriate quantities of carbon stored in and above their soil and to initiate or expand the use of precision agriculture on their farms. This act seeks to leverage and enhance existing state and federal cost-sharing programs for farm, ranch, and aquaculture operations.”

UPDATE: This bill passed the Senate on March 12, 2020, and the House on March 12, 2020. It was signed by the Governor on April 3, 2020.

The second is SB 6306 – 2019020 which creates the Washington soil health initiative.

“The legislature finds that healthy soil is a cornerstone of a high quality of life on earth and that soil health is integral to supporting agricultural viability, promoting positive environmental outcomes, and ensuring the long-term availability of nutritious food.

It is the intent of the legislature that the mission of the Washington soil health initiative be the promotion of collaborative soil health research, education, demonstration projects, and technical assistance activities designed to identify, promote, and implement soil health stewardship practices that are grounded in sound science and that can be voluntarily and economically implemented by farmers and ranchers across Washington’s diverse agricultural communities, climates, and geographies.”

UPDATE: This bill passed the Senate on March 9, 2020 and the House on March 10, 2020. It was signed by the Governor on April 2, 2020.

Fixing Climate Change – Boosting Nature’s Cooling System – Fixing The System

This exciting article from Fixing the System discusses soil as the engine of our planet’s cooling and carbon capture system.

Here’s an excerpt from the article:

“Rich soils exponentially increase the capture of water and carbon
What is powerful about healthy soil, and it really is the central element of the whole sponge discussion, is that now we have 66% of the volume of the matrix which is available for infiltrating and retaining water. That retained water is what can sustain plant growth. Because of these voids, and the increased surface area exposed by them, this healthy soil can vastly increase the availability of nutrients. Now we have the phosphorus, the calcium, and the zinc all exposed for microbial activity.

So the bio-productivity of that soil increases exponentially, simply by creating those voids. The rootability of these soils vastly increases, that is the roots can grow, and penetrate and proliferate. Instead of 6 inches, they can grow down to 6 feet, or 20 feet, so the volume of soil resource that is now available for plant growth, and the drawdown of carbon that we mentioned earlier, is exponentially increased.

Soil formation is the engine of nature’s cooling and carbon capture system
So the whole bio-productivity of these healthy soils, the resilience of those soils, the capacity to infiltrate, to buffer, to extend life vastly increases. This process is what nature did to create the biosystem, to create the hydrology, and in very simple terms, that is all we have to do.

The process is taking sunlight, carbon dioxide and water to produce plants, using photosynthesis to create sugars, and fungi and microorganisms that convert those sugars into stable soil carbon, which is just the carbon based organic detritus or ‘bed springs’. This process is how the Earth ran 95% of its heat dynamics and its natural hydrological cooling.

So, if we have to draw down 20 billion tonnes of carbon, if we have to rebuild this soil-carbon sponge, we simply need to copy nature, and speed up the soil formation process.”

Ancient Soils found in Western Australia

A week or so ago, scientists reported that soils collected in Western Australia contain tiny micrometeorites, compact balls of cosmic dust. When these soils were formed, about 2.7 billion years ago, cosmic debris was penetrating our atmosphere and seeding the ground with cosmic dust which persists in our soils today.

High-resolution microscope view of a tiny iron micrometeorite the size of a grain of sand. Analysis of these particles shows that Earth’s atmosphere used to contain a lot more carbon dioxide 2.7 billion years ago. Image via Andrew Tomkins/ Penn State.

The study of these micrometeorites is revealing the chemistry of Earth’s atmosphere nearly three million years ago and should also reveal the chemistry, and possibly some of the biology, of our ancestral soils.

These new peer-reviewed findings were published in the journal Proceedings of the National Academy of Sciences on January 21, 2020, with one of the authors, Owen Lehmer, from the University of Washington. As the authors explain:

“Carbon dioxide concentrations have varied widely over the Earth’s 4.54-billion-year history. This new work helps quantify the elements that made up Earth’s atmosphere in the very distant past.

The tiny iron micrometeorites that were studied are no larger than grains of sand. They were discovered in ancient soils – called paleosols – that are about 2.7 billion years old. The soils were collected in the Pilbara region of Western Australia. These scientists believe the micrometeorites fell from space during the Archean eon, when the sun was weaker than today.”

Riverday School Students Study Tardigrades

In January 2020, students at Riverday School in Spokane, WA did a variety of projects around tardigrades. Students created posters, took samples, and visited Gonzaga University to view live tardigrades. The students are supporting the initiative to make tardigrades Washington State’s micro-animal.

Here is a short video of their work on tardigrades. This footage was shot by the students themselves.

Here is the full video as shot and produced by the students.

There are also lots of pictures of the students during their trip to Gonzaga, as well as the teachers involved and the posters the students made.

The Tardigrade nominated as Washington State’s Official Micro-Animal

Tardigrade: Proposed Official State Micro-Animal of Washington

Two Washington State schools are nominating the Tardigrade as Washington State’s Micro-Animal. The science students at the Friday Harbor High School on San Juan Island and the students at Riverday School in Spokane have studied the Tardigrade as part of their science curriculum and found it to be worthy of becoming the Washington State Micro-Animal. The Tardigrade, which means “slow stepper” and is sometimes referred to as the “water bear” or “moss piglet,” is among the most resilient animals alive today, having survived the last five mass extinctions. They are found in fossil records 530 million years old. A native of Washington State, found in every county and habitat, it lives in mosses, lichens, marine and freshwater sediments, soil, seawater, freshwater, glaciers, hot springs, deserts, and rain forests. They are important ecologically because they eat other micro-organisms, such as crop-destroying nematodes, as well as plant cells, and help to clean both soil and water. Due to its amazing ability to withstand extremes, such as boiling mud pots in Yellowstone, glaciers on mountaintops, the vacuum of space, extreme drought, and radiation, the Tardigrade is being studied for new methods of adapting to climate change, as well as for preventing radiation damage from cancer treatments. Tardigrades may also be the first colonists on the moon since they crash-landed there in August of 2019. According to an international expert on Tardigrades, Lukasz Kaczmarek, they are likely to have survived because “Tardigrades can survive pressures that are comparable to those created when asteroids strike Earth, so a small crash like this is nothing to them.” This and many other extreme achievements of the Tardigrade make it the perfect Micro-Animal for the Evergreen State.

UPDATE: Washington state high school students attended legislative sessions in Olympia in support of making the tardigrade the state micro-animal.

Below are pictures of the students at the statehouse. Featured in one of the pictures is Representative Alex Ramel.

Before the hearing, Representative Alex Ramel took a few moments to talk to the students that would be testifying.