Science Special - Biochar Basics

Biochar is a fascinating carbon-negative technology.  It is created through the heating of biomass feedstocks (wood, crop wastes, manure, etc.) in low or no oxygen conditions; this oxygen-deprived process is called pyrolysis.  Biochar acts as a carbon sequestration technology by storing the carbon dioxide absorbed by plants during growth within the char.  

Pictured above: Biochar product created during a slow pyrolysis process

Pictured above: Biochar product created during a slow pyrolysis process

One of the major drivers behind biochar research and industry efforts is its potential to act as an effective soil amendment. Recent research has been spurred by historic terra preta soils found in the Amazon basin. These soils, enhanced with biochar thousands of years ago by indigenous populations, were found to be significantly more fertile than surrounding untreated, red soils. This boost in soil fertility has motivated scientific interest, yet many are calling for additional trials to investigate the interaction between feedstocks, pyrolysis processes, soils, climates, and crops to better understand the best way to reduce emissions, minimize energy consumption, and maximize revenue. 

To learn more about biochar, take a look through the links below:

(1) The Overview - Johannes Lehmann and Stephen Joseph. “Biochar for Environmental Management: An Introduction.” February 2009.

This brief synopsis of the biochar industry is the most cited paper on biochar on Google Scholar and is written by one of the most prominent researchers in the field, Johannes Lehmann of Cornell Soil and Crop Sciences. It outlines the fundamentals of biochar, basic terminology, the history of biochar, uses of biochar, benefits of biochar, and its climate change mitigation potential. This document is a detailed, yet succinct, glance into the world of biochar.

(2) The Science - CSIRO. “Biochar, climate change and soil: A review to guide future research.” February 2009. Saran Sohi et al.

This document, whose primary author (Saran Sohi) is the lead researcher for the UK Biochar Research Centre, is both comprehensive and well organized. Although this document discusses many of the key aspects of biochar (and thus, could be the document used for any of the 4 categories identified here), it does a great job of consolidating the status of scientific understanding of multiple key issues in the field: the magnitude and mechanisms of agronomic benefits, its ability to address climate change, as well as future research needs.

(3) The Industry - International Biochar Initiative. “2013 State of the Biochar Industry.” March 2014. Stefan Jirka and Thayer Tomlinson.

A look at the state of the biochar industry with key metrics: retail price of biochar, number of biochar-related publications, etc. The paper explores how biochar is faring in the real world, and some of the major obstacles that have prevented incorporation into large-scale agricultural markets.

(4) The Policy - National Resources Defense Council. “Biochar: Assessing the Promise and Risks To Guide U.S. Policy.” November 2010. Stephen Brick.

Chapter 3 of this document, entitled “Recommended Research Agenda to Support U.S. Biochar Policy Development” gives a highly specific policy recommendation for biochar research. In addition to making the standard call for increased funding and research efforts, this NRDC paper calls for “five to 10 biochar production systems along with a coordinated national field trial program.” The paper then gives a program outline, establishes a timetable of this program, and an estimated budget, all in just 2 pages!

(5) The Fun Video - "Waste No More" MindFuel

A young girl and a piece of biochar (apparently from Brooklyn) engage in an battle of wills over who should get credit for the increased yields of a biochar-enhanced garden patch.