Dr. Ellen Graber received the award of “Scientist of the Year” for 2013 last month for achievements in the ever expanding field of biochar – charcoal created through the pyrolysis, or thermochemical decomposition, of biomass – from the Academic Committee of the Volcani Center, the Agriculture Ministry’s research arm. Researching “biochar”, the carbon-rich black substance also known as biological charcoal, is Ellen’s modest contribution to the global fight against climate change.
Dr. Graber is a researcher at the Volcani Center’s Institute of Soil, Water and Environmental Sciences in Beit Dagan. Her journey into the field stemmed from a desire to explore the possibilities of using biochar to improve soil fertility and mitigate greenhouse gas emissions that lead to climate change.
Engineers are tasked with finding inexpensive, clean and efficient ways to carbonize waste biomass (such as crop and orchard residues, yardwaste, manure) through a pyrogenic process that generates gaseous and liquid biofuels, as well as solid energy-rich products, i.e., biochar. Biochar can also be utilized to generate energy, but Graber’s research primarily focuses on the use of the product as a soil amendment which may have fertility-enhancing properties.
Graber said that “it’s a really new field”. However, researchers around the world are now fervently working on the subject.
Scientists have discovered that the half-life of biochar in the soil is hundreds to thousands of years or more, such that carbon that originated in the atmosphere as CO2 but was converted to plant material via photosynthesis ends up sequestered in the soil essentially permanently – a carbon-negative process. Dr. Graber explained that this process may offer many benefits to soil, such as improving water-holding capacity, boosting plant growth, reducing soil acidity, reducing nutrient leaching, increasing water retention, and reducing irrigation and fertilizer requirements.
Although Dr. Graber sees a potentially important future for biochar – what she calls the “biochar vision” – she cautions that the product is still in its infancy and cannot be recognized as a “magic bullet” for all soil and climate issues. Furthermore, there are still many unknown elements involved in how to use it, in what cropping systems, at what dosages, and in what types of soil, she explained.
There are also several technological and economic uncertainties at this time. She said, “from a scientific perspective it’s amazing”. “Maybe it will fulfill its potential. If it does, it’s one of a number of strategies that will need to be employed. It’s not going to be standalone.”
It is possible that if biochar can improve plant health and performance by making them more disease resistant and stronger, it could potentially lead to a reduced need for fertilizer or pesticides, Graber inferred.
Meanwhile, it may have the advantage of being able to permanently remove carbon dioxide from the environment, due to its ability to sequester carbon.
In addition to all the positive effects of biochar, one particular element that scientists will need to focus on along the way are any negative impacts it might have in the soil, particularly as it remains there for hundreds to thousands of years, Graber pointed out. She stated, “we need to start small and then see what happens”.
Dr. Graber and her research team at the Volcani Center are working with biochar under conditions in which obviously positive attributes – like water-holding capacity and nutrient content – are controlled, in order to determine if plants are developing better simply from the biochar.
She explained,” this is what we call the delta, the biochar effect that we’re interested in”.
In addition, she said her team was the first in the world to discover that adding biochar to soil might improve plants’ system-wide immuno-defenses.
Going forward, some of the research in the field that Dr. Graber has identified as still lacking includes pinpointing mechanisms as to how biochar impacts crop yield and soil physical condition, evaluating agronomic values of biochar use, assessment of biochar value to intensive and extensive agriculture, estimating changes in water-use efficiency, finding engineering solutions for pyrolysis, quantifying carbon sequestration and energy production, determining optimal pyrolysis conditions, and identifying different wastes that can be treated by this method.
Her laboratory is looking especially for identifying how biochar impacts crop yields as well as plant health, and whether it can help remediate contaminated soils. They are researching, for example, if it can tie up contaminants and prevent them from being mobilized in places like urban brownfields.
She explained that the biochar can perhaps improve the soil by removing the toxins from contaminated soil and thus enabling plant growth. “I also see this as a good start for biochar because, anyway, these soils are dead,” she said. “So if I can rejuvenate them, that would be great.”
Via the Jerusalem Post, published on June 30, 2014. Click here for the original article.