Major J B Nguyen Lehmann J Rondon J
Major J, B, Nguyen Lehmann J, Rondon J, Hockaday M, Goodale WC, Joseph C (2010 a) S, Masiello Fate of. CA soil-applied (2010) Temperature black carbon: sensitivity downward of black migration, carbonleaching decomposition and soiland respiration. oxidation. Glob Environ Change Sci. Biol Tech 16: 1366 -1379 DOI: 10. 1021/es 903016 y Modeling black carbon in the environment Bente Foereid, Johannes Lehmann, Julie Major Crop and Soil Sciences, Cornell University • Black carbon (BC) is produced in fires and is assumed to be stable in the environment • “Biochar” is BC intentionally produced for soil amendment • BC has not yet been explicitly introduced into carbon turnover models • Here we make a simple model accounting for loss of BC by decomposition and horizontal as well as vertical movement out of the area Results Lab data for decomposition Nguyen et al. , 2010 Environ Sci Tech 44, 3324– 3331 Whitman , 2010 M. Sc. thesis, Cornell University Model structure Field data for leaching Predicted and measured CO 2 production. Data from Major et al. 2010 Predicted and measure BC in topand sub-soil. Data from Major et al. 2010 Major et al. , 2010 Glob Change Biol 16: 1366 -1379 Conclusions 100 y 2000 y • Erosion is poorly quantified, but probably Effect of changing parameter values, erosion the largest flux of BC out of a given area rate ± 50%, slow pool turnover rate 500 -5000 • A two pool model can adequately describe y, alternative values for temperature and moisture modifier BC decomposition dynamics Next step – earth system model, CLM • Decomposition rate of the slowest carbon pool is unimportant on time-scales < 100 y • Downwards movement is small as a mass flux, but not the only downward flux of BC
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