THE IDENTIFICATION AND QUANTIFICATION OF OXYGENATED POLYCYCLIC AROMATIC HYDROCARBONS IN DISSOLVED BLACK CARBON FROM BIOCHAR

The proposed benefits of black carbon (BC) in biochar (residues of the incomplete combustion of biomass) as a carbon-negative soil amendment have led to its wide application in soils. However, recent studies have shown that BC in biochar may not be as refractory in the soil environment as previously assumed. For example, mobilization or transformation of the organic molecules in biochar may occur. Many of these molecules are referred to collectively as dissolved black carbon (DBC). Previous studies have shown that compounds found in DBC, such as polycyclic aromatic hydrocarbons and oxygenated polycyclic aromatic hydrocarbons (PAHs and OPAHs, respectively), if mobilized can have adverse effects on aquatic and terrestrial organisms. This study will identify and quantify aromatic organic compounds including OPAHs, in aqueous leachates from a range of biochar. These experiments will improve our understanding of how organic compounds in biochar may be mobilized and transformed, and as a result will help identify how DBC plays a role in the environmental C cycle.