Australian climate-carbon cycle feedback reduced by soil black carbon

A - Papers appearing in refereed journals

Lehmann, J., Skjemstad, J., Sohi, S., Carter, John, Barson, M., Falloon, P., Coleman, K., Woodbury, P. and Krull, E. 2008. Australian climate-carbon cycle feedback reduced by soil black carbon. Nature Geoscience. 1, pp. 832-835.

AuthorsLehmann, J., Skjemstad, J., Sohi, S., Carter, John, Barson, M., Falloon, P., Coleman, K., Woodbury, P. and Krull, E.
Abstract

Annual emissions of carbon dioxide from soil organic carbon are an order of magnitude greater than all anthropogenic carbon dioxide emissions taken together1. Global warming is likely to increase the decomposition of soil organic carbon, and thus the release of carbon dioxide from soils2,3,4,5, creating a positive feedback6,7,8,9. Current models of global climate change that recognize this soil carbon feedback are inaccurate if a larger fraction of soil organic carbon than postulated has a very slow decomposition rate. Here we show that by including realistic stocks of black carbon in prediction models, carbon dioxide emissions are reduced by 18.3 and 24.4% in two Australian savannah regions in response to a warming of 3 ∘C over 100 years1. This reduction in temperature sensitivity, and thus the magnitude of the positive feedback, results from the long mean residence time of black carbon, which we estimate to be approximately 1,300 and 2,600 years, respectively. The inclusion of black carbon in climate models is likely to require spatially explicit information about its distribution, given that the black carbon content of soils ranged from 0 to 82% of soil organic carbon in a continental-scale analysis of Australia. We conclude that accurate information about the distribution of black carbon in soils is important for projections of future climate change.

Year of Publication2008
JournalNature Geoscience
Journal citation1, pp. 832-835
Digital Object Identifier (DOI)doi:10.1038/ngeo358
Open accessPublished as green open access
Funder project or codeSEF
Microbial function in nitrogen and carbon transformations
Dynamics of organic carbon in soil
Publisher's version
Copyright license
CC BY
Supplemental file
Copyright license
CC BY
Output statusPublished
Publication dates
Online16 Nov 2008
ISSN1752-0894
PublisherNature Publishing Group

Permalink - https://repository.rothamsted.ac.uk/item/8q113/australian-climate-carbon-cycle-feedback-reduced-by-soil-black-carbon

31 total views
7 total downloads
0 views this month
0 downloads this month
Download files as zip