Biochar: Grow Bigger, Better Veggies While Slowing Global Warming
August 20, 2008—
There’s a new player on the organic gardening front. It's called biochar, and it could be good medicine for the planet as well as for crops, because it can help mitigate global warming by sequestering carbon that would otherwise be released into the atmosphere.
Amazon natives have used it for centuries to improve their soil and grow better crops. Now it’s being made by Michigan Technological University students on the Upper Peninsula of Michigan.
The product of a slow-burning charcoal-creation process, biochar can vastly improve soils for growing food and other plants.
"Eight-hundred and eighty percent," says Michigan Tech faculty member Michael Moore "We didn't believe it either, so we kept investigating, and soil with biochar and fertilizer indeed was 880 percent more productive than soil with only fertilizer."
Studies have shown that, when mixed into the soil, the charcoal acts as a sponge, holding water and promoting growth of beneficial microbes, and it can stay in the soil for hundreds or even thousands of years.
To test the process, Moore’s class tried both vertical and horizontal placement of a 55-gallon barrel containing the fire. They discovered that the horizontal drum allowed for better burning.
"We burned sticks, twigs and even pallets," says Gary Franz, an industrial technology senior. "We got it going and then slowly covered it. After a four-to-five-hour burn, we let it sit for a day.” The result was lightweight charcoal chunks that can be tilled into soil.
Leaves, branches and yard trimmings, sawdust and wood chips can be used to produce biochar. “You can burn nearly anything carbon-based and formerly living," Franz says.
Doesn’t burning add to the problem of greenhouse gases?
"Because of the nature of the burn, the carbon released is less," says Dane Heimerman, a fifth-year mechanical engineering major. "Fifty percent of the carbon is released, compared to 80 percent in normal burning, and some burn processes actually capture the gases and put them back into the fire. Most importantly, when the charcoal is returned to the ground, it is actually carbon negative."
The seven-week course is part of a science and society curriculum. “We acknowledge that we are not scientists," says Michelle McCoy, a third-year scientific and technical communications major. "But we wanted to approach this from a community aspect, getting the word out about this process, which has great potential."
The students are encouraging their neighbors to try biochar. They’re considering using it in community gardens, promoting the idea at the upcoming county fair and assessing the feasability of a community biochar project.
For more information go to http://composing.org/hu2506summer/.
Michigan Technological University is a leading public research university, conducting research, developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 120 undergraduate and graduate degree programs in engineering, forestry and environmental sciences, computing, technology, business and economics, natural and physical sciences, arts, humanities and social sciences.
Michigan Technological University (www.mtu.edu) is a leading public research university developing new technologies and preparing students to create the future for a prosperous and sustainable world. Michigan Tech offers more than 130 undergraduate and graduate degree programs in engineering; forest resources; computing; technology; business; economics; natural, physical and environmental sciences; arts; humanities; and social sciences.