There is a popular saying among organic gardeners: “feed the soil not the plants”. For the past 80 years, organic gardeners have fed their soils with a wide range of composts, from the home-made, high-fertility wormy stuff to nutritionally-balanced nursery-bought bags based on peat.

But recently, an additive has been discovered, or rather rediscovered, prompting excitement among gardeners. Available alone or now as pre-mixed, peat-free compost, the wonder material is biochar, a charcoal-like substance produced through the oxygen-free, slow burning of woody biomass garden cuttings, grasses, crop waste.

THE demand for energy production as well as agriculture's need for soil improvement is often incompatible. But biofuel and biochar made in the same process could soon become a reality. Curtin University's Fuels and Energy Technology Institute is halfway through a $4.7 million research project that uses mallee trees as the feedstock to produce liquid fuel.

The two stage process converts the biomass into a liquid bio-oil which can be transported to a refinery to produce liquid biofuel. Director Professor Chun-Zhu Li said the high nutrient biochar produced from the process was a source for carbon sequestration that could be used to improve soil conditions. "The carbon in the biochar comes from the carbon dioxide in the air when the plant grows," Professor Li said.

Nitrous oxide is a potent greenhouse gas and a precursor to compounds that contribute to the destruction of the ozone. Intensively managed, grazed pastures are responsible for an increase in nitrous oxide emissions from grazing animals' excrement. Biochar is potentially a mitigation option for reducing the world's elevated carbon dioxide emissions, since the embodied carbon can be sequestered in the soil. Biochar also has the potential to beneficially alter soil nitrogen transformations.

A graduate student in biofuels at Iowa State University is researching what’s called biochar as a possible remedy to concerns about climate change and greenhouse gas emissions. Lernardo del Campos says biochar is similar to charcoal except it’s not used as fuel but instead, may be able to capture harmful carbons from the air, like carbon dioxide.

“It’s supposed to be wonderful, one of the main tools for sequestering CO2,” says del Campo. “It has many environmental benefits.” Del Campo, a 29-year-old from Uruguay, says capturing carbon dioxide is only half the battle, as that ties up vital oxygen. With biochar, he says the CO2 can be broken up and the oxygen is released back into the atmosphere.

The current international food system is “totally broken,” leaving one-sixth of the global population hungry, one-sixth malnourished and one-sixth over-nourished, Montgomery Fellow Dan Barber said in a lecture in Filene Auditorium on Tuesday.

Although he is a chef, Barber — who also co-owns the New York-based Blue Hill restaurants — emphasized the importance of how food is produced rather than focusing on how it is cooked, citing the health and environmental benefits of food produced through sustainable agricultural systems, as well as improvements in the quality of the ultimate product.

. Stone Barns’ grass is completely green, while that of other nearby farms is so degraded that the farmers choose to chemically treat it, according to Barber. Barber also discussed Blue Hill’s enthusiasm for testing new cooking methods. After experiments with new methods for feeding pigs left the farm with large amounts of lumber, Stone Barns began utilizing biochar — pulverized charcoal — as a fertilizer, which produced better-tasting, larger and more nutritious vegetables, Barber said. The Darthmouth

The projected rise in global temperatures could be cut in half in coming years if world governments focused on reducing emissions of two harmful pollutants - black carbon and ground-level ozone, including methane - rather than carbon dioxide alone, according to a U.N. study released Wednesday.

The study, "Integrated Assessment of Black Carbon and Tropospheric Ozone," by the U.N. Environment Programme, shows the impact that the two short-lived pollutants have on the environment, compared with carbon dioxide, which can stay in the atmosphere for decades.

"I think what this study does that hasn't been done in the past is look at the contributions to global warming by gases with short lifetimes," said Steve Seidel, vice president of policy analysis for the Pew Center on Global Climate Change.

Black carbon, a component of soot, is a threat to human health and is known to hasten the melting of snow. Ground-level ozone kills farm crops and also adversely affects health. Reducing the two, the study said, would improve health outcomes in the regions where they are implemented and "slow the rate of climate change within the first half of this century."

The impact from reducing short-lived pollutants such as black carbon and ground-level ozone such as methane is more immediately felt. Carbon dioxide remains in the atmosphere for years, so the effects of reducing the emissions take longer to register.

To reduce black carbon emissions, the study recommends placing a ban on open-field burning of agricultural waste, replacing industrial coke ovens with modern recovery ovens, introducing clean-burning biomass cook stoves for cooking and heating in developing countries and eliminating high-emitting vehicles. Read more Washington Post I PEW Research Center

Biochar researchers have expanded their research to around 350 sites on the North Coast, including coffee, macadamia and sugar cane farms.

Principal research scientist Lukas Van Zwieten said trials at the Wollongbar Primary Industries Institute had shown a 100% increase in the production of corn and faba beans and significant increases in nitrogen in the soil, whereas other trials had shown no significant influence from the biochar.

Biochar is a charcoal-like substance made from organic waste that can enhance soil productivity and store carbon.

“Different biochar have different properties depending on the material they are made from and the processing conditions,” he said.

Biochar is a key technology for reaching low carbon dioxide atmospheric concentration targets.

The negative emissions that can be produced by BECCS has been estimated by the Royal Society to be equivalent to a 50 to 150 ppm decrease in global atmospheric carbon dioxide concentrations^[3] and according to the International Energy Agency, the BLUE map climate change mitigation scenario calls for more than 2 gigatonnes of negative emissions with BECCS in 2050. BECCS Wikipedia