New directions in black carbon organic geochemistry

Biochar: Pyrogenic Carbon for Agricultural Use - A Critical Review

“…The quantification of pyrogenic C is of paramount importance to evaluate its role in soil C stocks and its fate in the environment, but is a great methodological challenge (Derenne and Largeau, 2001;Masiello, 2004;Simpson and Hatcher, 2004;Novotny et al, 2006Novotny et al, , 2007Hammes et al, 2007). The reason is that, first of all, the pyrogenic C pool must be considered in a continuum model of carbonization (Figure 3) (Masiello, 2004), which is very complex and comprises different products, ranging from slightly charred, degradable biomass to highly condensed, refractory soot, with gradual changes in properties and structures, in which the co-existence of several of the continuum products is common.…”

“…The reason is that, first of all, the pyrogenic C pool must be considered in a continuum model of carbonization (Figure 3) (Masiello, 2004), which is very complex and comprises different products, ranging from slightly charred, degradable biomass to highly condensed, refractory soot, with gradual changes in properties and structures, in which the co-existence of several of the continuum products is common. Etelvino Henrique Novotny et al According to Masiello (2004), pyrogenic C measurement techniques could be grouped into six general classes: microscopic; optical; thermal; chemical; spectroscopic; molecular marker; and also combinations of these six techniques.…”

Long term change in chemical properties of preindustrial charcoal particles aged in forest and agricultural temperate soil

“…On one hand, the presence of BC in geological records since the Devonian and of millennial BC in a range of soils at global scale provides evidence that some persists for a very long time in the environment (Schmidt and Noack, 2000). On the other hand, the content of BC stored in soil is low with respect to annual production rate from wildfires, which demonstrates that large amounts are lost from soil (Schmidt and Noack, 2000;Masiello, 2004;Schmidt, 2004), possibly by microbial decomposition (Baldock and Smernik, 2002;Hamer et al, 2004;Wengel et al, 2006), erosion (Rumpel et al, 2006) or dissolution and transport with water fluxes (Hockaday et al, 2007;Jaffé et al, 2013). The longevity of BC in soil seems to depend on both intrinsic quality and the environmental conditions where it is deposited (Bird et al, 2015).…”

Black carbon contents and distribution in sediments from the southeastern Brazilian coast (Guanabara Bay)

“…For example, Oen et al 10 found that in harbor sediments from Norway with BC/TOC ratio in the range of 6.4 to 12.3% (similar to those found in many stations in Guanabara Bay) the distribution of PAH was dominated by the presence of BC. Since it is well documented that interaction by sorption to BC particles reduces bioaccumulation and biodegradation of organic contaminants like polycyclic aromatic hydrocarbons (PAH) and dioxins, 5,7,21 the results of the present work indicate the need for considering the BC fraction as a factor controlling the fate and effect of PAH contamination in Guanabara Bay.…”

“…2,3,5,6 In the last 20-30 years, the research on BC expanded from the traditional field of atmospheric science to a growing interest in the organic geochemistry of these particles, including sources, transport and accumulation in aquatic systems, and characterization of chemical composition and structure. 7,8 Such interest draws from the increasing emissions of anthropogenic-derived black carbon originated from agricultural activities and consumption of fossil fuels associated with the complex role of BC in environmental process. 9,10 BC particles may contribute to global warming through absorption of solar irradiance and decrease of Earth's albedo when present in polar ice sheets, and may be a carrier for carcinogenic contaminants with possible health effects.…”