A portion of black carbon in soils globally also comprises condensed aromatic carbon in the
form of soot particles. This, in turn, can be confused with soot similarly formed in fossil fuel
combustion. Such black carbon is considered to lie at the most stable end of a black carbon
continuum (Masiello, 2004). Over extended timescales the physical transport of this material
through the soil and into water and sediment is inevitable and is seen in its accumulation in
marine sediment (Masiello et al., 1998). This observation highlights the potential to confuse
physical transport of biochar from a trial site for oxidative loss. It also indicates the
importance of such processes to the sequestration of carbon in the natural carbon cycle
(Smittenberg et al., 2006).