The next revolution in agriculture and greenhouse gas reduction may be a 3000-year old farming practice of adding biomass charcoal to the soil. The practice was re-discovered by archeologists who were studying a site in the central-Amazon basin. Some 1500 years earlier the indigenous tribes had enriched the soil using charcoal from animal bone and tree bark. The soil remains today some of the richest and most fertile soil yet found.
Scientists from the American Chemical Society have begun a five-year study of the use of biomass charcoal for soil enrichment in order to understand its impact on fertilization, soil carbon changes, crop productivity and any impact on the microorganisms in the soil.
The practice holds promise for several reasons:
- Soil need only be fertilized once with this method and the effect lasts for hundreds to thousands of years.
- The resulting agricultural method is carbon-negative since the enriched soil traps and holds carbon in the soil, which may offer significant benefits to decreasing global warming from agriculture and reducing greenhouse gases in the atmosphere.
- The charcoal required would be made from biomass like compost, leaves, wood chips and organic matter resulting in a non-toxic and stable fertilizer.
- Smoke generated during the burning process, called pyrolysis, could even be collected and cooled to use as a bio-oil renewable energy source.
- The practice could be a low-cost way to enrich soil in the most impoverished areas where poor soil quality and drought have led to high rates of hunger and malnutrition.
Scoring points on the altruism scale, scientists involved say they will not seek a patent on the process if the study is successful. They want the practice they call “Black Gold Agriculture” put into use as soon and as widely as possible. It’s a fascinating prospect that an answer to help save our earth would come from that very earth, and was in use for thousands of years.
Currently the only foreseeable downsides to the approach is the cost to transport the biochar mass and the need for different farming tools to spread the product over large areas.