Biochar quiets microbes, including some plant pathogens

Rice University News: In the first study of its kind, Rice University scientists have used synthetic biology to study how a popular soil amendment called “biochar” can interfere with the chemical signals that some microbes use to communicate. The class of compounds studied includes those used by some plant pathogens to coordinate their attacks.

Biochar is charcoal that is produced — typically from waste wood, manure or leaves — for use as a soil additive. Studies have found biochar can improve both the nutrient- and water-holding properties of soil, but its popularity in recent years also owes to its ability to reduce greenhouse gases by storing carbon in soil, in some cases for many centuries.

The new study, published online this month in the journal Environmental Science and Technology, is the first to examine how biochar affects the chemical signaling that’s routinely used by soil microorganisms that interact with plants. “A potted plant may look tranquil, but there are actually a lot of conversations going on in that pot,” said study co-author Joff Silberg, associate professor of biochemistry and cell biology and of bioengineering at Rice. “In fact, there are so many different conversations going on in soil that it was impractical for us to determine exactly how biochar was affecting just one of them.”

So Silberg and colleagues used the tools of synthetic biology — and a refined experimental setup that Silberg initially drafted with his son’s spare Lego bricks — to establish a situation where just one microbial conversation was taking place and where biochar’s effects on that conversation could be measured.

The study is the latest from Rice’s interdisciplinary Biochar Research Group, which formed in the wake of Hurricane Ike in 2008 when the city of Houston called for ideas about how to get rid of the estimated 5.6 million cubic yards of fallen trees, broken branches and dead greenery left behind by the storm. The Rice Biochar Group won the $10,000 grand prize in the city’s “Recycle Ike” contest and used the money to jump-start a wide-ranging research program that has since received support from the National Science Foundation, the Department of Energy, Rice’s Faculty Initiative Fund, Rice’s Shell Center for Sustainability and Rice’s Institute of Bioscience and Bioengineering....

Rice University graduate student Shelly Hsiao-Ying Cheng shows the tool she created with Rice biochemist Joff Silberg to conduct two experiments in the same dish, one where biochar had a chance to interfere with a microbial conversation and another where it didn’t. CREDIT: Jeff Fitlow/Rice University

Enriching glacial soils with biochar

Ann Perry at the US Department of Agriculture News: Adding a charred biomass material called biochar to glacial soils can help reduce emissions of the greenhouse gases carbon dioxide and nitrous oxide, according to U.S. Department of Agriculture (USDA) scientists.

Studies by scientists with USDA's Agricultural Research Service (ARS) are providing valuable information about how biochar-the charred biomass created from wood, plant material, and manure-interacts with soil and crops. As part of this effort, ARS scientists in St. Paul, Minn., are studying biochar activity in soils formed from glacial deposits. ARS is USDA's chief intramural scientific research agency, and this work supports the USDA priorities of responding to global climate change and ensuring international food security.

Soil scientists Kurt Spokas and John Baker, who both work at the ARS Soil and Water Management Research Unit in St. Paul, found that amending glacial soils with biochar made from macadamia nut shells reduced a range of greenhouse gas emissions.

After the researchers amended the soils with biochar at levels ranging from 2 to 60 percent, emission levels for the greenhouse gases carbon dioxide and nitrous oxide were suppressed at all amendment levels. But the suppression in nitrous oxide emission was notable only in soils amended with 20, 40 or 60 percent biochar.

The amended soils also had lower microbial production of carbon dioxide and lower volatilization rates for the pesticides atrazine and acetochlor. The scientists plan to follow these findings with new investigations on how volatile organic compounds (VOCs) in biochar affect soil microbe activity. As part of this work, they have already identified 200 different VOCs on some biochars....

Lettuce growing in Minnesota field plots amended with 20,000 pounds of macadamia nut shell biochar per acre. The study evaluated how the biochar affects crop yield, soil fertility, and greenhouse gas production from the field. Photo by Amanda Bidwell

Is biochar a part of the climate change solution?

David Lee in the Jamaica Observer: … What are the beneficial attributes of biochar, as incorporated in soil? Detailed examination of terra preta suggests that pyrolysis by the Amazon natives had been done at relatively low temperature, perhaps 350 C, instead of about 500 C for charcoal nowadays. This would have resulted in the retention of presumably beneficial volatiles which would normally be lost in the high temperature process. It is also undergoing a parallel and comparable interest as a soil ameliorant.

The practical consequence of [its physical] properties, as reported by many accounts, is an almost "miraculous" ability to promote plant growth, in comparison with unamended soils as control, and also when, as control, conventionally fertilised soils were used.
Growth improvement, of course, is dependent on original soil quality, it being minimal where the soil is ideal in all respects, and very marked when it is poor.

Perhaps as important as the agricultural implications, is the promise of biochar for climate change mitigation. For each cycle of pyrolysis and at least partial use of the resultant char for soil amendment, part of the carbon that was a major portion of the ligneous material becomes sequestered for an indefinite period. It would take many cycles, on a vast scale, to effect significantly reduced levels of atmospheric carbon dioxide. But no schemes considered are free of this scale constraint.

…Only Belize, it seems, of the English-speaking Caribbean countries, is presently participating in biochar studies. It should behove us to have a local investigation into the topic for the reasons already stated, and also for the implications for the local agricultural situation, which benefits that biochar potentially offers….

That's Amazonian terra preta on the right, shot by Bruno Glaser or Rsukiennik, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Aggressive geoengineering won't halt sea level rise

Science Daily: New findings by international research group of scientists from England, China and Denmark just published suggest that sea level will likely be 30-70 centimetres higher by 2100 than at the start of the century even if all but the most aggressive geo-engineering schemes are undertaken to mitigate the effects of global warming and greenhouse gas emissions are stringently controlled.

"Rising sea levels caused by global warming are likely to affect around 150 million people living in low-lying coastal areas, including some of the world's largest cities," explained Dr Svetlana Jevrejeva of the National Oceanography Centre.

Most scientists agree that anthropogenic carbon dioxide emissions contribute greatly to global warming, and that these emissions need to be controlled if damaging future impacts such as sea-level rise are to be averted. But if we fail to do so, is there a 'Plan B'?

Scientists have proposed ways of 'geo-engineering' the Earth system to tackle global warming, thereby reducing its impact on both the main contributors of sea level rise: thermal expansion of ocean water and melting of glaciers and ice sheets. Jevrejeva and her colleagues have modelled sea level over the 21st century under various geo-engineering schemes and carbon dioxide emission scenarios.

… The researchers argue that perhaps the least risky and most desirable way of limiting sea-level rise is bioenergy with carbon storage (BECS). Biofuel crops could be grown on a large-scale, and carbon dioxide released during their combustion or fermentation could be captured, and the carbon stored as biochar in the soil or in geological storage sites.

…."Substituting geo-engineering for greenhouse emission control would be to burden future generations with enormous risk," said Jevrejeva.

Waves crashing on the shore. Athor: Fir0002, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License.

Biochar could fight climate change

Kevin McCullan in the News Tribute (Tacoma, Washington): The most comprehensive analysis yet of the worldwide potential of biochar -- a charcoal-like substance -- shows it could offset up to 1.8 billion metric tons annually of the world's human-caused greenhouse gas emissions, according to a new study. Biochar also can be used to improve poor soil and help it hold water, which can boost production of food crops, according to the study, which was co-authored by a Richland-based scientist. And the process used to make it -- pyrolysis -- yields energy and bio-oil that can be used as fuel.

Biochar can be produced on scales large or small -- at industrial facilities or in a small farming operation. But its largest potential is as a tool to stabilize carbon from common sources, such as plants and wood or animal waste, and store it in the soil for decades, according to the study published this week in the journal Nature Communications.

"This is the most complete bottoms-up study of biochar and how it can combat climate change to date," said Jim Amonette, a soil chemist at Pacific Northwest National Laboratory and study co-author.

…Amonette said biochar presents "one of the few ways we can create power while decreasing carbon dioxide levels in the atmosphere. And it improves food production in the world's poorest regions by increasing soil fertility."…

Terra preta (or biochar) on the right, shot by Bruno Glaser, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license.

Is biochar the answer for agriculture?

American Society of Agronomy: Scientists demonstrate that biochar, a type charcoal applied to soils in order to capture and store carbon, can reduce emissions of nitrous oxide, a potent greenhouse gas, and inorganic nitrogen runoff from agriculture settings. The finding will help develop strategies and technologies to reduce soil nitrous oxide emissions and reduce agriculture’s influence on climate change.

A research team led by Bhupinder Pal Singh from Industry and Investment New South Wales and Balwant Singh from the University of Sydney, tested the effects of four types of biochar on nitrous oxide emission and nitrogen leaching from two different soil varieties. Their results are reported in the July-August 2010 Journal of Environmental Quality, published by the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America.

The study revealed for the first time that interactions between biochar and soil that occur over time are important when assessing the influence of biochar on nitrogen losses from soil. The scientists subjected soils samples to three wetting-drying cycles, to simulate a range of soil moistures during the five-month study period, and measured nitrous oxide emissions and nitrogen runoff.

Initially, biochar application produced inconsistent effects. Several early samples produced greater nitrous oxide emissions and nitrate leaching than the control samples. However, during the third wetting–drying cycle, four months after biochar application, all biochars reduced nitrous oxide emissions by up to 73%, and reduced ammonium leaching by up to 94%. The researchers suggest that reductions in nitrous oxide emissions and nitrogen leaching over time were due to “ageing” of the biochars in soil.

“The impacts of biochars on nitrous oxide emissions from soil are of interest because even small reductions in nitrous oxide emissions can considerably enhance the greenhouse mitigation value of biochar, which is already proven to be a highly stable carbon pool in the soil environment,” according to senior author Bhupinder Pal Singh. “This research highlights that impacts of biochar on nitrogen transformations in soil may change over time and hence stresses the need for long-term studies to assess biochar’s potential to reduce nitrogen losses from soil.”…

Charcoal from wood, which is close to biochar but not the best source. Shot by Lamiot, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported

‘Biochar’ could ease Colorado beetle-kill pain

Aspen Times: As the U.S. Forest Service looks for ways to use vast amounts of beetle-killed wood, an ages-old process called biochar is emerging as an option. Pre-Columbian natives in North and South America already knew that adding charcoal to certain soils would help with fertility and water retention. Now, scientists say it can also help prevent the build-up of greenhouse gases.

“I got tuned into a different way of looking at our treatments for biomass,” said Bernie Weingardt, explaining how scientists working at Forest Service research stations started exploring the idea of trying to prevent the decaying wood from adding heat-trapping greenhouse gases to the atmosphere. Weingardt is a retired Forest Service ranger who headed Colorado's Dillon Ranger District between 1986 and 1989. He later became the Pacific Southwest regional forester. He spoke Thursday morning at a forest health task force meeting in Frisco.

“We’ve been logging and burning all along and never looked at the carbon emissions issue,” Weingardt said. “So we started some pilot projects to track the carbon footprint.” Scientists with the agency’s research stations used data from biomass and co-generation facilities in the region to get an idea of how much carbon can be captured or used through alternate processes.The biochar process is yet another tool that could be used in conjunction with other treatments, he said.

Along similar lines, Summit County has started an ambitious composting program, combining wood chips from beetle-killed trees with other organic materials to manufacture a marketable product that can used in landscaping and re-vegetation projects.

One byproduct of the biochar process is a synthetic gas that can be used as fuel. Weingardt suggested that the gas could help run a pellet plant, or some other industrial facility that processes beetle-killed wood as part of a big-picture solution. At the end of the process, the charcoal can be used to amend soil. In California, vintners have been using it successfully to boost vineyard productivity, Weingardt said. It could also be used on a broader scale in reforestation projects….

The Pine Forest of Mio, 1858, from 36 Views of Mount Fuji

Biochar and reforestation may offer better global cooling potential than ocean fertilization

Mongabay: The first comprehensive assessment of the climate cooling potential of different geoengineering schemes has been conducted by researchers at the University of East Anglia (UEA). The results are published in the journal Atmospheric Chemistry and Physics Discussions Among the findings, according to a statement from UEA:

Enhancing carbon sinks will take nearly 100 years to bring atmospheric carbon dioxide levels back to pre-industrial levels and will require sharp cuts in emissions.

Stratospheric aerosol injections and sunshades in space — a concept supported by Paul J. Crutzen, winner of the 1995 Nobel Prize in Chemistry for his work on the hole in the ozone layer — have "by far the greatest potential to cool the climate by 2050" but carry the greatest risk.

Adding phosphorous to the ocean via existing activities may have greater long-term carbon sequestration potential than iron or nitrogen fertilization schemes.

Sequestering carbon by planting forests and as 'bio-char' — charcoal added back to the soil — have greater short-term cooling potential than ocean fertilization. Bio-char also offers to potential to boost soil productivity for agriculture.

Increasing the reflectivity of urban areas could reduce urban heat islands but will have minimal global effect. The same goes for schemes involving ocean pipes and stimulating biologically-driven increases in cloud reflectivity.

The beneficial effects of some geo-engineering schemes have been over-estimated and mis-calculated in previous calculations….

Dr Alexander Thorkel (Albert Dekker) from Dr. Cyclops (1940)

Biochar as a tool to fight climate change

Environment News Service: …[S]cientists, environmental groups and policymakers forging the next world climate agreement see the charred organic material that they have dubbed "biochar" as a tool for replenishing soils and as a tool for combating global warming.

Christoph Steiner, a University of Georgia-Athens research scientist in the Faculty of Engineering, was a contributor to the biochar proposal submitted by the UN Convention to Combat Desertification at a side event held last week at the UN climate change conference meeting in Poland. The new climate change agreement will replace the Kyoto Protocol, which expires in 2012. "The potential of biochar lies in its ability to sequester - capture and store - huge amounts of carbon while also displacing fossil fuel energy, effectively doubling its carbon impact," said Steiner, a soil scientist whose research in the Amazon Basin originally focused on the use of biochar as a soil amendment.

….Steiner explains that almost any kind of organic material - peanut shells, pine chips and even poultry litter - can be burned in air-tight conditions in a process called pyrolysis. The byproducts are biochar, a highly porous charcoal that helps soil retain nutrients and water, and gases and heat that can be used as energy.

Because the carbon in biochar resists degradation, it can sequester carbon in soils for hundreds of years, making it a permanent sink - a natural system that soaks up the greenhouse gas carbon dioxide from the atmosphere.…Steiner said scientists estimate biochar from agriculture and forestry residues can potentially sequester billions of tons of carbon in the world's soils.

…"Removing crop residues for bioenergy production reduces the organic matter accumulating on agricultural fields and thus the soil organic carbon pool, which depends on constant input of decomposing plant material," Steiner said. "In contrast, pyrolysis with biochar carbon sequestration produces renewable energy, sequesters CO2 and cycles nutrients back into agricultural fields."…

A comparison of "terra preta" in the Amazon (on the right) with conventional soil in the region. Shot by Bruno Glaser, Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2