Sustainable biochar to mitigate global climate change.
Production of biochar (the carbon (C)-rich solid formed by pyrolysis of biomass) and its storage in soils have been suggested as a means of abating climate change by sequestering carbon, while simultaneously providing energy and increasing crop yields. Substantial uncertainties exist, however, regarding the impact, capacity and sustainability of biochar at the global level. In this paper we estimate the maximum sustainable technical potential of biochar to mitigate climate change. Annual net emissions of carbon dioxide (CO(2)), methane and nitrous oxide could be reduced by a maximum of 1.8 Pg CO(2)-C equivalent (CO(2)-C(e)) per year (12% of current anthropogenic CO(2)-C(e) emissions; 1 Pg=1 Gt), and total net emissions over the course of a century by 130 Pg CO(2)-C(e), without endangering food security, habitat or soil conservation. Biochar has a larger climate-change mitigation potential than combustion of the same sustainably procured biomass for bioenergy, except when fertile soils are amended while coal is the fuel being offset.
School of the Environment and Society, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
Dominic
D
Woolf
James E
JE
Amonette
F Alayne
FA
Street-Perrott
Johannes
J
Lehmann
Stephen
S
Joseph
D002245:Carbon Dioxide / Q000378:metabolism; D002606:Charcoal; D057231:Climate Change; D008697:Methane / Q000378:metabolism; D009609:Nitrous Oxide / Q000378:metabolism
C540010:biochar; D002245:Carbon Dioxide; D002606:Charcoal; D009609:Nitrous Oxide; D008697:Methane