Scientists Search for Carbon Solutions in Amazonia's 'Black Earth'
by Max Ajl - Feb 25th, 2009
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Imagine if in a poverty-stricken sector of the equatorial band, littered with acidic soils barely fit for farming, there were jet-black patches of dirt, seeded with charcoal and so fertile that they could be planted continuously for over 40 years without applying fertilizer.
Then imagine that those patches were so loaded with carbon that they had six to seven times the amount of carbon per pound of the surrounding soils, that Western scientists could partially replicate the process through which the black earth was made, and that by burying carbon in earth they could augment soil fertility and, perhaps, leach carbon out of the atmosphere and reverse global warming.
Perhaps the jig is already up—too much detail. What we’re talking about is terra preta, or more colloquially, biochar, the Amazonian miracle soil.
NASA Climatologist James Hansen has endorsed terra preta—literally black earth—as a carbon “draw-down strategy.” British chemist James Lovelock, originator of the Gaia hypothesis, says it is the “one way we could save ourselves.”
So let’s check it out. But first, what is it?
Terra preta was first documented in the Brazilian Amazon by Dutch soil scientist Wim Sombroek in the 1950's. Similar deposits exist in Ecuador, Peru, Benin, Liberia and South Africa. They are thousands of years old.
In Brazil, they were created by throwing fecal matter, organic refuse, charcoal, broken pottery, and other detritus into the Amazonian soil. Whether this was done intentionally or not is unclear. But the enormously fertile terra preta, usually running in patches along riverbanks, supported massive pre-Colombian civilizations, numbering in the hundreds of thousands to millions.
Its main ingredient is biochar—the charcoal. It was and is biologically active. Micro-organisms and fungi nest in its pores, helping to keep the soil abnormally fertile and nutrient-rich. And the carbon, created by burning organic plant waste, secures it safely underground where it can stay for decades or centuries.
What’s perhaps most interesting about biochar is that it appears to be replicable using human technology.
To create biochar – and produce energy at the same time – biomass, such as degrading trees, shrubs, grasses, or organic wastes, can be heated to 400 or 500 degrees with the complete or partial exclusion of oxygen, a technique called pyrolysis. As Cornell ecologist Christopher Lemann explains:
At these temperatures, biomass undergoes exothermic processes and releases a multitude of gaseous components in addition to heat. … Both heat and gases can be captured to produce energy carriers such as electricity, bio-oil, or hydrogen for household use or powering cars.
Such a system produces between three and nine times more energy than is input. Depending on the configuration of the heating system, 50 percent of the biomass can be converted into biofuel and 50 percent stored in carbon—the biochar. Compare to carbon sequestration after simply burning off biomass: under 3 percent of the total carbon in the biomass, or letting it naturally decompose, which sequesters between 10 and 20 percent of the carbon. The biochar can then be placed into carbon-starved soils.
A study published in 2006 in Mitigation and Adaptation Strategies for Global Change suggests that tropical zones are excellent places to use biochar for another reason: the frequent use of slash-and-burn agriculture.
If instead of slashing and burning covering vegetation, farmers in such regions were to slash-and-char, using small kilns, 12 percent of annual emissions resulting from land-use chance could be offset. The biochar resists conversion to CO2 for a long time, but it is unclear how long, because of the time-scales involved. The biochar may also reduce methane and nitrous oxide emissions from soil, two extremely potent greenhouse gases.
In that same study, the authors note:
The projected amount of renewable fuels would potentially yield an amount of sequestered bio-char of 5.5–9.5 PgCyr−1, if pyrolysis were to be used. … The maximum potential sequestration of 9.5 PgCyr−1 would exceed today’s anthropogenic emissions from fossil fuels of 5.4 PgCyr−1 even if no fossil fuels are substituted by renewable fuels in the future.
The numbers are astounding but immediately raise a question: Is biochar viable?
Certainly it is technologically and politically viable. The UN Convention to Combat Desertification submitted a proposal at Poznan to make it a Clean Development Mechanism, and the proposal will be under consideration at UN Framework Convention on Climate Change negotiations in Copenhagen later this year.
Economic viability is a separate issue. One company working to produce small-scale biochar production units is Ecovolve. Its founder, Jason Aramburu, observes, “most gasification systems require expensive gas cleaning equipment, which is only economical at a size of several megawatts or more.” But bringing biomass to concentrated plants in order to process it, turn it into biochar and biogas, and then redistribute it is an energy intensive endeavor.
Ecovolve’s units—still in testing stages—allow for biomass to be turned into biochar at the same location that the organic waste is produced. The units also produce energy, making them a carbon-negative energy source.
So, while biochar has not quite made it, it may be close. A bill to provide funding to biochar initiatives in the United States was proposed in 2007 by former Sen. Ken Salazar, now the secretary of the Interior. The proposal is still languishing in committee. One wonders what they’re waiting for.
Max Ajl is a writer living in Brooklyn, N.Y. He has written on Latin American politics and economics for the Guardian, the New Statesman and Society, and is a research associate for NACLA.
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had no idea
Wow, I had no idea that this existed, but it sounds like a good initiative that may help some of the poorest countries in the world. I hope they pass that bill soon.
Thanking...
Thanks for this great post...........
Biochar Soil Technology....Husbandry of whole new orders of life
Biochar Soil Technology.....Husbandry of whole new orders of life
Biotic Carbon, the carbon transformed by life, should never be combusted, oxidized and destroyed. It deserves more respect, reverence even, and understanding to use it back to the soil where 2/3 of excess atmospheric carbon originally came from.
We all know we are carbon-centered life, we seldom think about the complex web of recycled bio-carbon which is the true center of life. A cradle to cradle, mutually co-evolved biosphere reaching into every crack and crevice on Earth.
It's hard for most to revere microbes and fungus, but from our toes to our gums (onward), their balanced ecology is our health. The greater earth and soils are just as dependent, at much longer time scales. Our farming for over 10,000 years has been responsible for 2/3rds of our excess greenhouse gases. This soil carbon, converted to carbon dioxide, Methane & Nitrous oxide began a slow stable warming that now accelerates with burning of fossil fuel.
Wise Land management; Organic farming and afforestation can build back our soil carbon,
Biochar allows the soil food web to build much more recalcitrant organic carbon, ( living biomass & Glomalins) in addition to the carbon in the biochar.
Biochar, the modern version of an ancient Amazonian agricultural practice called Terra Preta (black earth, TP), is gaining widespread credibility as a way to address world hunger, climate change, rural poverty, deforestation, and energy shortages… SIMULTANEOUSLY!
Modern Pyrolysis of biomass is a process for Carbon Negative Bio fuels, massive Carbon sequestration,10X Lower Methane & N2O soil emissions, and 3X Fertility Too.
Every 1 ton of Biomass yields 1/3 ton Charcoal for soil Sequestration, Bio-Gas & Bio-oil fuels, so is a totally virtuous, carbon negative energy cycle.
Biochar viewed as soil Infrastructure; The old saw, "Feed the Soil Not the Plants" becomes "Feed, Cloth and House the Soil, utilities included !". Free Carbon Condominiums, build it and they will come.
As one microbologist said on the TP list; "Microbes like to sit down when they eat". By setting this table we expand husbandry to whole new orders of life.
Charles Mann ("1491") in the Sept. National Geographic has a wonderful soils article which places Terra Preta / Biochar soils center stage.
http://ngm.nationalgeographic.com/2008/09/soil/mann-text
Biochar data base;
http://terrapreta.bioenergylists.org/?q=node
NASA's Dr. James Hansen Global warming solutions paper and letter to the G-8 conference, placing Biochar / Land management the central technology for carbon negative energy systems.
http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf
The many new university programs & field studies, in temperate soils; Cornell, ISU, U of H, U of GA, Virginia Tech, JMU, New Zealand and Australia.
Glomalin's role in soil tilth, fertility & basis for the soil food web in Terra Preta soils.
UNCCD Submission to Climate Change/UNFCCC AWG-LCA 5
"Account carbon contained in soils and the importance of biochar (charcoal) in replenishing soil carbon pools, restoring soil fertility and enhancing the sequestration of CO2."
http://www.unccd.int/publicinfo/AWGLCA5/menu.php
This new Congressional Research Service report (by analyst Kelsi Bracmort) is the best short summary I have seen so far - both technical and policy oriented.
http://assets.opencrs.com/rpts/R40186_20090203.pdf .
Given the current "Crisis" atmosphere concerning energy, soil sustainability, food vs. Biofuels, and Climate Change what other subject addresses them all?
This is a Nano technology for the soil that represents the most comprehensive, low cost, and productive approach to long term stewardship and sustainability.
Carbon to the Soil, the only ubiquitous and economic place to put it.
Cheers,
Erich J. Knight
Shenandoah Gardens
540 289 9750
Biochar Studies at ACS Huston meeting;
578-I: http://a-c-s.confex.com/crops/2008am/webprogram/Session4231.html
579-II http://a-c-s.confex.com/crops/2008am/webprogram/Session4496.html
665 - III. http://a-c-s.confex.com/crops/2008am/webprogram/Session4497.html
666-IV http://a-c-s.confex.com/crops/2008am/webprogram/Session4498.html
Most all this work corroborates char soil dynamics we have seen so far . The soil GHG emissions work showing increased CO2 , also speculates that this CO2 has to get through the hungry plants above before becoming a GHG.
The SOM, MYC& Microbes, N2O (soil structure), CH4 , nutrient holding , Nitrogen shock, humic compound conditioning, absorbing of herbicides all pretty much what we expected to hear.
Company News & EU Certification
Below is an important hurtle that 3R AGROCARBON has overcome in certification in the EU. Given that their standards are set much higher than even organic certification in the US, this work should smooth any bureaucratic hurtles we may face.
EU Permit Authority - 4 years tests
Subject: Fwd: [biochar] Re: GOOD NEWS: EU Permit Authority - 4 years tests successfully completed
Doses: 400 kg / ha – 1000 kg / ha at different horticultural cultivars
Plant height Increase 141 % versus control
Picking yield Increase 630 % versus control
Picking fruit Increase 650 % versus control
Total yield Increase 202 % versus control
Total piece of fruit Increase 171 % versus control
Fruit weight Increase 118 % versus control
HOMEPAGE 3R AGROCARBON: http://www.3ragrocarbon.com
Also:
EcoTechnologies is planning for many collaborations ; NC State, U. of Leeds, Cardiff U. Rice U. ,JMU, U.of H. and at USDA with Dr.Jeffrey Novak who is coordinating ARS Biochar research. This Coordinated effort will speed implementation by avoiding unneeded repetition and building established work in a wide variety of soils and climates.
www.EcoTechnologies.com
Hopefully all the Biochar companies will coordinate with Dr. Jeff Novak's soils work at ARS;
http://www.ars.usda.gov/pandp/people/people.htm?personid=24434
I spoke with Jon Nilsson of the CarbonChar Group, in their third year of field trials ;
An idea whose time has come | Carbon Char Group
He said the 2008 trials at Virginia Tech showed a 46% increase in yield of tomato transplants grown with just 2 - 5 cups (2 - 5%) "Biochar+" per cubic foot of growing medium. http://www.carbonchar.com/plant-performance
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