High-Resolution Record of Pyrogenic Polycyclic Aromatic Hydrocarbon Deposition during the 20th Century

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• 作者：Ana L&uacute ; cia C. Lima ; Timothy I. Eglinton ; and Christopher M. Reddy
• 刊名：Environmental Science & Technology
• 出版年：2003
• 出版时间：January 1, 2003
• 年：2003
• 卷：37
• 期：1
• 页码：53 - 61
• 全文大小：221K
• 年卷期：v.37,no.1(January 1, 2003)
• ISSN：1520-5851

文摘

A high-resolution record of polycyclic aromatic hydrocarbon(PAH) deposition in Rhode Island over the past ~180years was constructed using a sediment core from theanoxic Pettaquamscutt River basin. The record showedsignificantly more structure than has hitherto been reportedand revealed four distinct maxima in PAH flux. Thecharacteristic increase in PAH flux at the turn of the 20thcentury was captured in detail, leading to an initialmaximum prior to the Great Depression. The overall peakin PAH flux in the 1950s was followed by a maximumthat immediately preceded the 1973 Organization of PetroleumExporting Countries (OPEC) oil embargo. During the mostrecent portion of the record, an abrupt increase in PAH fluxbetween 1996 and 1999 has been found to follow aperiod of near constant fluxes. Because source-diagnosticratios indicate that petrogenic inputs are minor throughoutthe record, these trends are interpreted in terms ofpast variations in the magnitude and type of combustionprocesses. For the most recent PAH maximum, energyconsumption data suggest that diesel fuel combustion, andhence traffic of heavier vehicles, is the most probablecause for the increase in PAH flux. Systematic variationsin the relative abundance of individual PAHs in conjunctionwith the above changes in flux are interpreted in relationto the evolution of combustion processes. Coronene,retene, and perylene are notable exceptions, exhibitingunique down-core profiles.