In the current economic climate, its been a bit rough for those that want to go green on a budget. Not everyone can...Read the rest of this article
Ancient fertilizer biochar joins modern fight against greenhouse gases
by Bryce Wolfe on August 15, 2010
What do bone fragments, cow patties and banana peels have in common? They all help gardens grow. When processed into a charcoal-like substance called biochar instead of being burned directly for fuel, researchers say organic materials could offset as much as 12 percent of the world's greenhouse gases.
Benefits of biochar include improved soil fertility, reduced nitrous oxide and methane emissions from the soil and, during processing, the production of gas and oil that can be used to generate electricity in place of fossil fuels, according to a recent study published in the journal Nature Communications.
The study focused on sources of biomass not used for food, such as corn stalks, rice husks, livestock manure and yard trimmings. Researchers calculated the carbon content of each material and found that, at maximum, using biochar could offset up to 1.8 billion tons of carbon emissions each year. Their most conservative estimate put the carbon offset at just under 1 billion tons each year.
However, researchers stated that reducing greenhouse gas emissions at these levels will require significant commitment from governments and citizens around the world. Everyone will need to change the way they think about carbon. The study concluded that biochar would be most beneficial if tilled into the planet's poorest soils, which have lost their ability to hold onto nutrients due to erosion. Biochar increases fertility by locking in water and nutrients.
In Western Kenya, villagers often use traditional open fires that require a large amount of firewood. As the land is stripped, kindling is sometimes taken illegally from national forests. The International Biochar Initiative describes how providing villagers with redesigned stoves and enabling them to use biochar has reduced deforestation and increased yield on farms.
The study researchers also noted that no farmland needs to be diverted into making biochar in place of food crops. To be made sustainably, the plant waste should only be taken from existing sources, like the remnants of food crops and livestock. Some biomass should be left on the soil to protect it from erosion and it should be processed using modern technologies that fully recover energy and eliminate soot, methane and nitrous oxide emissions. Biochar is produced by heating biomass in the absence of oxygen, a process known as low-temperature pyrolysis.
Humans have been using biochar for thousands of years to improve soil quality. Adding biochar to soils creates a positive feedback cycle, encouraging greater plant growth and greater biomass for future biochar production. There is virtually no downside to the ancient fertilizer as long as it's produced sustainably. Biochar is more stable than biomass and can trap greenhouse gases like carbon dioxide for hundreds of years. So instead of throwing out that yard waste, consider helping the atmosphere and donating it to your regional biochar group.