The “Magic” of Biochar: Recent results from the iBRN

Biochar. Photo courtesy Simon Dooley via Creative Commons License.

by Ellen R. Graber
Volcani Center, Agricultural Research Organization, Israel

When scientists and laypeople alike learn about biochar for the first time, they usually are intrigued by the seeming “magic powers” of this black powder. People with gardens and farms want to know how to use it, and scientists want to understand whether the stories they hear about it can possibly be true, and if yes, how does it work?

“Our group recently completed two studies that push us a bit forward in understanding the why of biochar. ”

Biochar is the solid product of treating organic matter wastes by pyrolysis, which is the technical word for burning organic materials in the absence of oxygen. Generally, we are familiar with combustion, that is, burning that takes place in the presence of oxygen. In an oxygen-containing environment, all the organic matter is eventually combusted to gases, mainly carbon dioxide and water vapor. By contrast, during pyrolysis, there are several final products, including biochar, bio-oil, and “syngas” (also known as synthesis gas). 

By now, plenty of research studies in the laboratory, greenhouse, and field have shown that when biochar is added to soil, it can improve plant growth and health. This is not a universal result, however: sometimes adding biochar has no effect, and sometimes even negative effects are reported. As a result, knowing what is happening is not enough. We need to know why it is happening. Once we know the why, it will be possible to harness the positive effects and eliminate or minimize the negative ones. 

Our group recently completed two studies that push us a bit forward in understanding the why of biochar. We discovered that biochar-stimulated improvements in plant growth and health are strongly linked to increased microbial diversity and changes in the metabolic potential of microbes in the root zone. Much as human health and development are affected by the microbes occupying our gut, so plant health and development are affected by the microbes intimately associated with the plant roots. Biochar improves the functioning and increases the diversity of these microbes, which corresponds to the increasing general consensus that soil additions that enhance microbial diversity have important benefits for ecosystem functioning. We have found that these changes are primarily triggered by the recalcitrant carbon backbone of the biochar and other tightly bound components that are part of biochar. 

Much more research is still needed, but this gives an indication of the path scientists can follow to determine how to design and use biochar in the future.

The original research articles can be found in: Kolton et al. and Jaiswal et al.

The film: "Solutions from the Land"

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Seeds growing in Biochar at the Volcani Center. Stills from the film Solutions from the Land

Biochar—is a soil-enrichment approach to cultivation that is being explored in many places in the world. While its long-term effects are still under investigation, many people are looking to biochar as a possible response to two of the world’s most dire issues: hunger and climate change. Israel, which has been rising to the challenges of growing crops in stubbornly difficult conditions for many years, is on the forefront in this field. 

“Biochar is a possible response to two of the world’s most dire issues: hunger and climate change.”

The two-part film Solutions from the Land includes “Saving the Soil: Israel Explores Biochar” and “Biochar: A New Path.” It highlights the work of Yoram Kapulnik, head of the Volcani Center   (the research arm of the Israeli Ministry of Agriculture), and award-winning Volcani scientist Ellen Graber; together they are experimenting with biochar with a view to improving impoverished soils and countering the adverse effects of chemicals and pesticides, while increasing crop yield. In the film, Yoram and Ellen visit a U.S. biochar facility, and take stock of how work is advancing on both sides of the Atlantic. The film also focuses on neuroscientist-turned-biochar-entrepreneur Nadav Ziv, surrounded by hundreds of thousands of date-palm trees near the Dead Sea; he explains that greenhouse gases taken out of the air by the growing palm trees are fixed via a process known as pyrolysis in the form of biochar, which can be used to great advantage. Each of these remarkable figures is contributing to Israel’s—and the world’s—progress in the area of sustainable agriculture. 

These stills are from the film Solutions from the Land available with the purchase of The Desert and the Cities Sing: Discovering Today’s Israel.

Scientist Ellen Graber and the Potentials of Biochar

Scientist Ellen Graber of the Volcani Center with biochar agriculturist Nadav Ziv. From the film Solutions from the Land

Ellen Graber is a founder of the Israel Biochar Research Network (iBRN). She is a highly charged, dynamic, and thoughtful woman—a prudent scientist who understands that we don’t yet know all there is to know about putting biochar into our soil. She cautions that it is not a “magic bullet” that will solve all our agronomic and climatic problems. But she also recognizes that the potentials of biochar are enormous. In 2013 Ellen was named Scientist of the Year by the Academic Committee of the Volcani Center for her work with what she calls the “biochar vision.” Volcani scientists and the iBRN are looking into biochar’s long-term effects in the earth, its impact on soil-borne and foliar diseases, how it acts in compost, and much more. They are also considering the major economic impact that biochar might have in the long run.         

“Ellen Graber and the Volcani Center are at work on a number of critical challenges facing our planet, from water shortage to the energy crisis to climate change to feeding the planet.”

Ellen and the Volcani Center are at work on a number of critical challenges facing our planet, from water shortage to the energy crisis to climate change to feeding the planet. As at so many other Israeli science centers, it is understood that whatever answers are uncovered here will have an effect not only in Israel, but around the world. In its best form, scientific research—unlike politics—is not bound by frontiers. Borders, after all, are not eternal, but knowledge is. Good researchers understand how vital it is to share what they learn: to give and receive. Luckily, Ellen Graber is there, looking out for us. 

Israel Biochar Research Network > 

Volcani Center >

Stills from the film Solutions from the Land, available with the purchase of The Desert and the Cities Sing: Discovering Today’s Israel. 

Biochar: a potential tool in the battle against climate change

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An aerial view, shows cows moving through the lush cover crop on a U.S. farm after the earth has been treated with biochar and tended organically. Photo courtesy Michael Arison

What exactly is biochar and how does it work? While it seems a very twenty-first-century topic, biochar has actually been around in some form for centuries: the pre-Colombian Amazonians developed a dark, rich, and fertile soil, terra preta, or “black earth,” using a similar method. In brief, biochar is a kind of charcoal made from organic materials that have undergone a firing process known as pyrolysis, which takes place in the absence of oxygen. Added to soil, biochar can improve fertility and, by “sequestering” carbon—that is to say, by not allowing it to be broken down easily or rapidly—can reduce emissions from the biomass that would otherwise naturally degrade into greenhouse gases. The carbon in biochar resists degradation—in fact, biochar can hold carbon in soil for hundreds, even thousands, of years—thus preventing it from re-entering the carbon cycle.

“If you could continually turn a lot of organic material into biochar, you could, over time, reverse the history of the last two hundred years. . . . We can run the movie backward. We can unmine some of the coal, undrill some of the oil. We can take at least pieces of the Earth and—this is something we haven’t done for quite a while—leave them Better Than We Found Them.
”

— Bill McKibben, conservationist and author

Biochar, to put it simply, is a method of replenishing soil with carbon, making it rich and fertile. It is also a potential tool in the battle against climate change. One of the chief causes of global warming is the overload of carbon dioxide as a “greenhouse gas” in the air: humans produce CO2 (chiefly by burning fossil fuels, such as coal, natural gas, and oil, for energy and transportation), and also have depleted natural systems—like forests—that remove CO2 from the atmosphere. Biochar has the potential to mitigate that process; in fact, well-designed biochar systems can actually be carbon negative, because they result in the net transfer of carbon (which began as carbon dioxide in the atmosphere) to the soil, where it can be stable for a very long time. In other words, biochar may present a way for us to start taking back some of the carbon that humans have poured into the atmosphere.