Lohmann, Rainer [faculty advisor, Graduate School of Oceanography]




sediment record; black carbon; Sequoia National Forest; environment


This project investigates the interaction between Black Carbon and Polycyclic Aromatic Hydrocarbons (PAHs) in lake sediments from Oriole Lake in Sequoia National Park California. The interaction between Black Carbon and PAHs is of interest because little is known with respect to the availability and the time scale within which black carbon adsorbs PAHs in a natural system. Black Carbon and PAHs both will eventually be degraded in the environment but the relevant timescales of sorption and degradation are unknown. Field work for this project was conducted July 16-21, 2007 at Oriole Lake in Sequoia National Park California. Sequoia National Park provides a unique environment for PAH and Black Carbon research in that its frequent natural fires are recorded in the giant Sequoias and in Park Service records. The relative isolation of Oriole Lake allowed for a clear sediment record that was primarily influenced by regional scale fire events. A strong correlation in the sediment of Black Carbon percentages to the historical recorded of local fires around Oriole Lake was found. Total PAHs showed neither a trend with time nor with Black Carbon Percentage, suggesting that in this sediment core the PAHs are not strongly bound by the Black Carbon. This project confirmed that Oriole Lake is indeed a prime location for analysis of PAH/ Black Carbon interactions and has provided the starting point for future research on the fire history of the Oriole Lake Watershed.