Biochar: The science behind the hype

Presented on April 5, 2013, by Kurt Spokas - USDA-ARS Soil Scientist Abstract: Biochar (a form of black carbon) has been recently heralded as an amendment to revitalize worn-out/weathered soils, increase soil carbon sequestration, enhance agronomic productivity, and enter into future carbon trading markets. Soil application has been the assumed target for biochar. Biochar has been shown to occasionally cause immense benefits to both crop yields and soil fertility when added to degraded/weathered soils, but simultaneously has a documented history of negative to negligible agronomic impacts. Past research, as far back as the 1800's, has demonstrated that biochar has variable properties, which spans the full spectrum of black carbon residuals. Thus, suggesting that biochar is not a panacea for all soils. The mechanisms behind these biochar impacts are complex with multiple potential hypotheses. This presentation will summarize on-going research into the mechanisms behind the mitigation potential for N2O emissions and the role of biochar in improving water quality through nitrate and agrochemical sorption/reactions. With population expansion and the finite area of tillable ground, improving nonproductive soils with biochar could be a vital key to future global food production, food security, and energy supplies. Download slides: http://hdl.handle.net/2142/106765