Quantifying Charcoal Degradation and Negative Priming of Soil Organic Matter with a 14 C-Dead Tracer

Converting biomass to charcoal produces physical and chemical changes greatly increasing environmental recalcitrance, leading to great interest in the potential of this carbon form as a long-term sequestration strategy for climate change mitigation. Uncertainty remains, however, over the timescale of charcoal’s environmental stability, with estimates varying from decadal to millennial scales. Uncertainty also remains over charcoal’s effect on other aspects of carbon biogeochemical cycling and allied nutrient cycles such as nitrogen. Radiocarbon is a powerful tool to investigate charcoal mineralization due to its sensitivity; here we report the results of a study using 14 C-dead charcoal (pMC=0.137±0.002) in organic-rich soil (pMC=99.76±0.46), assessing charcoal degradation over 55 days of incubation. Using this method, we discriminated between decomposition of indigenous soil organic matter (SOM) and charcoal by microorganisms. SOM was the major source of carbon respired from the soil, but there was also a contribution from charcoal carbon mineralization. This contribution was 2.1 and 1.1% on days 27 and 55, respectively. We also observed a negative priming effect due to charcoal additions to soil, where SOM mineralization was repressed by up to 14.1%, presumably arising from physico-chemical interactions between soil and charcoal

Biogeochemical cycle · Biology · Carbon cycle · Carbon fibers · Charcoal · Dissolved organic carbon · Ecosystem · Organic matter · Soil carbon · Soil organic matter · Soil water · Amazonian Archaeology and Ethnohistory · Cassava research and cyanide · Chemistry · Environmental Science · Recycling and Waste Management Techniques · Ecology · Environmental Chemistry · Soil Science

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  Open Access•Niels C Munksgaard, Anna V McBeath et al.•Radiocarbon•2019

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• Carbon Dioxide Capture Using a Zeolite Molecular Sieve Sampling System for Isotopic Studies ( 13 C and 14 C) of Respiration

  Open Access•S M L Hardie, M H Garnett et al.•Radiocarbon•2005

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• Processing of CO 2 Samples Collected Using Zeolite Molecular Sieve for 14 C Analysis at the Nerc Radiocarbon Facility (East Kilbride, UK)

  Open Access•M H Garnett, C Murray•Radiocarbon•2013

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• Processing of CO2 Samples Collected Using Zeolite Molecular Sieve for 14C Analysis at the Nerc Radiocarbon Facility (East Kilbride, UK)

  Mark Garnett•Radiocarbon•2013

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• Discussion Reporting of 14 C Data

  Open Access•Minze Stuiver, Henry A Polach•Radiocarbon•1977

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