Definitions
This website would mainly serve the soil and sediment community studying black carbon. In this context, some clarifications are given regarding the use of the term black carbon.
Black carbon (BC)
BC in soils and sediments is defined as a carbonaceous substance of pyrogenic origin, which is resistant to thermal or chemical degradation under the conditions applied in the methods used in the comparative study. According to estimates found in literature, >80 % of BC produced ends up in the soil, where it can reside for hundreds to thousands of years, being relatively resistant to biological and chemical breakdown (Forbes et al., 2006, Preston and Schmidt, 2006). Black carbon therefore represents a pool of C with a long residence time – in essence BC is a carbon sink. For soils and sediments, the light-absorbing characteristics of the substance are not part of our definition of black carbon. What is important is the chemical and thermal stability (and hence longevity) of BC either due to chemical recalcitrance that is evident from its aromatic structure or physical protection due to its surface functionality and binding with minerals and other organic compounds (Brodowski et al., 2005; Forbes et al., 2006).
Elemental carbon (EC)
This term is used in atmospheric sciences, and is in most cases referring to the fraction of carbon that is oxidised in combustion analysis above a certain temperature threshold, and only in the presence of an oxygen-containing atmosphere (Andreae & Gelencsér, 2006). The term EC is sometimes used interchangeably with BC.
References
Andreae, M.O., Gelencsér, A. 2006. Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols. Atmospheric Chemistry and Physics 6, 3131-3148.
Brodowski S., Amelung, W., Haumaier, L., Abetz, C., Zech, W. 2005. Morphological and chemical properties of black carbon in physical soil fractions as revealed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Geoderma 128, 116-129.
Forbes, M.S., Raison, R.J., Skjemstad, J.O. 2006. Formation, transformation and transport of black carbon (charcoal) in terrestrial and aquatic ecosystems. Science of the Total Environment 370, 190-206.
Preston, C.M., Schmidt, M.W.I. 2006. Black (pyrogenic) carbon: a synthesis of current knowledge and uncertainties with special consideration of boreal regions. Biogeoscience 3, 397-420.