This article is from our 2009/10 Annual Report, Redefining Conservation.

Over the past two years, a ‘buzz’ has been building amongst experts in the fields of climate change and agriculture. Media reports have highlighted a new product: one that promises to sequester CO2 in a cost-effective way, increase agricultural yields, reduce polluting run-off from agricultural land, and increase the efficiency of fertilizer and water use. This “new” product is called biochar. It is a complex substance with many possible variations in composition, structure and quality. When produced from wood fuel, we know it as charcoal.

Biochar’s first use as an agricultural amendment was by the indigenous cultures of the Amazon rainforest, thousands of years ago. By burying charcoal mixed with organic wastes, such as food scraps, the ancient people were able to turn poor, low fertility rainforest soils into fertile cropland. Scientists currently studying these soils (called terra preta) are amazed that they have retained their fertility to this day, without any further human inputs.

The modern, high-tech method of biochar production is called pyrolysis. Fuel – usually wood or agricultural waste, but any organic material can be used – is heated to a high temperature in a low-oxygen environment. The products generated include oil, gas and biochar. The latter can contain as much as half the carbon in the original fuel. The oil can be processed into a biofuel and/or a variety of different oil-based products, while the gas can be used to fuel the pyrolysis process itself. Biochar can be produced at a very high-tech scale – as at least one Canadian company is already doing so in Ontario – or at a low-tech, individual scale, using simple cooking stoves.

Adding biochar to soil provides two basic benefits. The first arises from the fact that most of the carbon in biochar resists decomposition by microbes in the soil. In essence, the concept is one of delaying the carbon cycle. Biological material that has been created by fixing atmospheric carbon through photosynthesis ordinarily delivers its carbon back into the atmosphere when the organic material decomposes. By delaying this decomposition, biochar effectively sequesters the carbon in soil. The second benefit has to do with soil health. Studies show that biochar can enhance nutrient-holding capacity, increase moisture retention and build biological biodiversity – substantially improving the soil’s health, fertility and resilience.

However, biochar has its detractors. Some question its value for Ontario’s young and relatively fertile soils. Although more research is needed, an early trial in Quebec suggests some increase in yields and increased fertilizer-use efficiency. OMAFRA’s soil specialists consider the positive claims for biochar as “intriguing but unproven,” and the ministry has already provided scientific support for new research.

Skeptics have also questioned the length of time the carbon in biochar will remain sequestered. While recent research suggests that the sequestration is very long term (i.e., hundreds or even thousands of years), caution and more research are definitely required.

Finally, some observers feel that if biochar were eligible for carbon credits it would put the world’s remaining natural areas at risk – as well as the human and ecological communities that depend on them. The concern is that large multinationals may convert these areas into crop or forest monocultures designed to fuel biochar production.

In current times, as in ancient times, biochar brims with promise. Several internationally acclaimed scientists have gone on record as supporting increased research and the development of policy and programs to promote biochar production and use. Despite its tantalizing promise, however, there are undeniable risks if the technology is misused.

The ECO encourages OMAFRA to give biochar research, both by its staff and in partnership with universities and the private sector, a very high priority. The ECO also encourages OMAFRA to begin to address the risks associated with biochar production, with an eye to the development of guidelines. In our 2008/2009 Annual Report, the ECO recommended that Ontario develop a provincial biofuels strategy to address the full ecological implications of the increased use of biomass energy. Guidelines for biochar production and use should be a major component of that strategy.

Also see:

• Can Biochar help save the planet?

This spring, the ECO found some biochar at a trade show. Biochar is charcoal, a stable form of carbon that will persist in the environment for a very long time, and assist in the biological and nutrient status of topsoil.

Here’s a short video from CNN:

David Nuttle helps us understand how the stuff may help save our planet.

Research by Johannes Lehmann, Ph.D., at Cornell University, has established that the addition of biochar to soils reduces soil acidity, helps improve availability of water for plants, and increases soil microbial activity therby providing natural fertility (thus, reducing the need for most fertilizers). At the same time, the biochar performs a carbon sequestration function benefiting the environment and reducing global warming.

A study that was published recently showed that biochar could offset up to 12% of greenhouse gases. Study co-author Jim Amonette, a soil chemist at the Department of Energy’s Pacific Northwest National Laboratory, said:

These calculations show that biochar can play a significant role in the solution for the planet’s climate change challenge…Biochar offers 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. It’s an amazing tool.

However, he cautioned that

Using biochar to reduce greenhouse gas emissions at these levels is an ambitious project that requires significant commitments from the general public and government … We will need to change the way we value the carbon in biomass.

(For more plain-language coverage of this report, see Science Daily, Ecoseed, Inhabitat and The New Republic.)

Another study showed that biochar reduces nitrous oxide emissions from soil by by 73%, and reduces inorganic nitrogen runoff from fields by up to 94%.  Senior author Bhupinder Pal Singh of Industry & Investment New South Wales said:

“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.”

Even Good Morning America is taking notice.

Tim Callahan, vice president of international development at re:char, stopped by “Good Morning America” today to talk about biochar.

“Biochar can be mixed in with your fertilizer, and when you’re planting to increase crop production up to 200 percent,” Callahan said. “As an added bonus 2.2 lbs of biochar offsets the carbon produced from three hours of your washer/dryer, 8.5 hours of a room air conditioning unit, or over two days of watching television.”

Some projects going on around the world:

• Biocharm Project: Biochar for Carbon Reduction, Soil Management and Sustainable Agriculture: A 12 month funded project, [to] look at the possible agronomic benefits which the addition of biochar can have to agricultural systems in South and South East Asia.
• Project on Biochar and African Dark Earths: This project investigates an overlooked dimension of African farmers’ management of soil fertility: the importance of charred carbon in soil systems and landscapes, and its potential contribution to sustainable and equitable land management.

Biochar is charcoal, a stable form of carbon that will persist in the environment for a very long time, and assist in the biological and nutrient status of topsoil.

It is the only possible viable carbon capture and storage technology that has the opportunity to both reduce greenhouse gas in the atmosphere, and enhance the productivity of our soils.

For more information about this company, please see dynamotive.com/

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