Feeding Biochar to Cows; An Innovative Solution for Improving Soil

Fertility and Farm Productivity

ABSTRACT
Addition of biochar produced through thermal decomposition of biomass has been seen as a strategy to improve soils and to sequester carbon. Recently, a number of authors have highlighted the barriers to wide scale implementation of the technology and the need to devise innovative profitable solutions.

In particular, there has been a suggestion that biochar utilisation needs to be developed with an integrated systems approach. An innovative program was implemented in 2012 on a 53ha farm in Western Australia to determine the costs and benefits of integrating biochar with animal husbandry and improvement of pastures.

Stephen Joseph, Doug how, Kathy Dawson, David R.G. Mitchell, Aditya Rawal, James Hook, Sarasadat Taherymoosavi, Lucas Van Zwieten, Joshua Rust, Scott Donne, Paul Munroe, Ben Pace, Ellen Graber, Torsten Thomas, Shaun Nielsen, Jun Ye, Yu Lin, G.X. Pan, Li Lianqing, Zakaria M. Solaiman

Biochar was mixed with molasses and feed directly to cows. The dung/biochar mixture was incorporated into the soil profile by dung beetles. While this innovative technology and practice was initiated by the farmer and was not established initially as an independent scientific trial, the researchers have gained a valuable insight into this unique practice through careful analysis of both the soil and the biochar extracted from the soil.

Our research studied the changes in soil properties over three years. Biochar extracted from fresh dung and from biochar extracted from the soil to a depth of 40cm was characterised. A preliminary financial analysis of the costs and benefits of this integrated approach was also undertaken.

This preliminary investigation concludes that this strategy is effective in improving soil properties and increasing returns to the farmer. It also concludes that the biochar absorbs nutrients from the cow’s gut and from the dung. Dung beetles can transport this nutrient rich biochar into the soil profile.

There is little evidence that the recalcitrant component of the biochar was reduced through reactions inside the gut or on or in the soil. Further research is required to quantify the long-term impact of integrating biochar and dung beetles into the rearing of cows.