Mitigation and Adaptation Strategies for Global Change

, Volume 11, Issue 2, pp 395–419

Bio-char Sequestration in Terrestrial Ecosystems – A Review

Authors

    • Department of Crop and Soil SciencesCollege of Agriculture and Life Sciences, Cornell University
  • John Gaunt
    • GY Associates Ltd.
  • Marco Rondon
    • Climate Change ProgramCentro Internacional de Agricultura Tropical (CIAT)
Article

DOI: 10.1007/s11027-005-9006-5

Cite this article as:
Lehmann, J., Gaunt, J. & Rondon, M. Mitig Adapt Strat Glob Change (2006) 11: 395. doi:10.1007/s11027-005-9006-5

Abstract

The application of bio-char (charcoal or biomass-derived black carbon (C)) to soil is proposed as a novel approach to establish a significant, long-term, sink for atmospheric carbon dioxide in terrestrial ecosystems. Apart from positive effects in both reducing emissions and increasing the sequestration of greenhouse gases, the production of bio-char and its application to soil will deliver immediate benefits through improved soil fertility and increased crop production. Conversion of biomass C to bio-char C leads to sequestration of about 50% of the initial C compared to the low amounts retained after burning (3%) and biological decomposition (< 10–20% after 5–10 years), therefore yielding more stable soil C than burning or direct land application of biomass. This efficiency of C conversion of biomass to bio-char is highly dependent on the type of feedstock, but is not significantly affected by the pyrolysis temperature (within 350–500 C common for pyrolysis). Existing slash-and-burn systems cause significant degradation of soil and release of greenhouse gases and opportunies may exist to enhance this system by conversion to slash-and-char systems. Our global analysis revealed that up to 12% of the total anthropogenic C emissions by land use change (0.21 Pg C) can be off-set annually in soil, if slash-and-burn is replaced by slash-and-char. Agricultural and forestry wastes such as forest residues, mill residues, field crop residues, or urban wastes add a conservatively estimated 0.16 Pg C yr−1. Biofuel production using modern biomass can produce a bio-char by-product through pyrolysis which results in 30.6 kg C sequestration for each GJ of energy produced. Using published projections of the use of renewable fuels in the year 2100, bio-char sequestration could amount to 5.5–9.5 Pg C yr−1 if this demand for energy was met through pyrolysis, which would exceed current emissions from fossil fuels (5.4 Pg C yr−1). Bio-char soil management systems can deliver tradable C emissions reduction, and C sequestered is easily accountable, and verifiable.

Keywords

black carboncarbon sequestrationcharcoalemissions tradingglobal warming potentialgreenhouse gas emissionssoilsterra preta de indio

Copyright information

© Springer Science+Business Media, Inc. 2006