This crumbly black substance is often made as a by-product of forestry and other industries. It is created when biomass is left in high-temperature, low-oxygen conditions, where it undergoes a process called pyrolysis. Long before its recent uptake in modern farming, biochar was created and added to soil by indigenous farmers in Amazonia from around the 5th Century BC, to form the rich black earth of the Amazon Basin known as “terra preta.”
…In 2012, a research group in Vietnam found that adding 0.5-1% biochar to cattle’s feed could reduce methane emissions by more than 10%, while other studies have found reductions of up to 17%. Studies on beef cows in the Great Plains of the US found that adding biochar to feed reduces cows’ methane emissions by between 9.5% and 18.4%. Given that methane makes up 90% of greenhouse gas emissions from cattle farming, this could considerably cut cattle’s environmental footprint.
…He was originally drawn to it not for its potential to reduce his herd’s methane emissions, but as a way to sequester more carbon into the soil. This had the dual prospect of sinking carbon and improving soil health.
“Due to the highly porous nature and high surface area of biochar, it improves soil’s ability to hold more water,” says Bhawana Bhatta, a soil science lecturer of the University of Melbourne. “The fine network of pores within biochar gives room for soil microorganisms to live. This increases the microbial diversity in the soil.”
…Enticed by the addition of molasses along with the biochar, Pow’s cattle dutifully chowed down their enriched feed, produced their cowpats, and then the beetles got to work. The bovine beetles then got started on the cows’ dung, working in pairs. The male brings the dung to the female beetles who dig a tunnel into the soil. Every time a beetle burrows into the soil, it also brings to the surface new soil with high levels of phosphorus, which acts as a natural [fertilizer.]
Studies over a three-year period on Doug’s farm showed an increase in total organic carbon, and enhancing soil fertility from when he first started. The research showed that he was also improving soil water retention and increasing the amount of carbon that was being retained in the soil.