Mass Spectrometry Imaging of Varved Sediments of the Santa Barbara Basin Reveals the Wildfire History in Southern California

Summary Wildfire-related biomarkers monosaccharide anhydrides (Mas) formed during biomass burning were analyzed using the direct and extraction-free approach of mass spectrometry imaging (MSI) in varved sediments of the Santa Barbara Basin (SBB) in order to reconstruct the recent wildfire history in southern California’s hinterland. The resulting laser-based MA record, spanning a period from AD 1900 to 2009 with approximately monthly resolution, strongly matches the areal extent of recorded wildfires since AD 1950. Potential constraints of MSI with respect to pyrolytic interaction of the laser with lignocellular biomass in the sediment, as well as a closer comparison with conventional chromatographic methods for separation of MA isomers will be needed to implement MSI as an approach for high-resolution wildfire reconstruction.