Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications
Polycyclic aromatic hydrocarbons (PAHs), produced via incomplete combustion of organics, convey signatures of vegetation burned in the geologic past. New and published burn experiments reveal how the quantity, distributions, and isotopic abundances of fire-derived PAHs were influenced by fuel types,...
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| Format: | Journal Article |
| Language: | English |
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PERGAMON-ELSEVIER SCIENCE LTD
2020
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| Online Access: | http://purl.org/au-research/grants/arc/DP130100577 http://hdl.handle.net/20.500.11937/90114 |
| _version_ | 1848765328935354368 |
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| author | Karp, A.T. Holman, Alex Hopper, Peter Grice, Kliti Freeman, K.H. |
| author_facet | Karp, A.T. Holman, Alex Hopper, Peter Grice, Kliti Freeman, K.H. |
| author_sort | Karp, A.T. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Polycyclic aromatic hydrocarbons (PAHs), produced via incomplete combustion of organics, convey signatures of vegetation burned in the geologic past. New and published burn experiments reveal how the quantity, distributions, and isotopic abundances of fire-derived PAHs were influenced by fuel types, burn conditions, and also phase. PAH concentrations were higher in burn residues from moderate burn temperatures (400–500 °C), and significantly lower in residues from cooler (<300 °C) or hotter (>600 °C) conditions, especially when oxygen was limited. PAH forms tended to be smaller in smoke samples and larger in residues, consistent with molecular physical and chemical properties. Plant functional types were distinguished by relative amounts of retene and dimethyl phenanthrene isomers. Isotopically distinct photosynthetic pathways of the burned material were reflected in the δ13C values of PAHs, which faithfully captured biomass signatures as well as the ∼12‰ offset between C3 and C4 plant types. PAH size, alkylation, and isotope characteristics can differentiate combusted plant types and distinguish between air-borne and sedimentary transport mechanisms. New proxy approaches using PAH amounts, distributions, and isotope signatures can aid and refine interpretations of paleofire ecology in the geologic record. |
| first_indexed | 2025-11-14T11:33:31Z |
| format | Journal Article |
| id | curtin-20.500.11937-90114 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:33:31Z |
| publishDate | 2020 |
| publisher | PERGAMON-ELSEVIER SCIENCE LTD |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-901142023-02-09T07:03:03Z Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications Karp, A.T. Holman, Alex Hopper, Peter Grice, Kliti Freeman, K.H. Science & Technology Physical Sciences Geochemistry & Geophysics Polycyclic aromatic hydrocarbons (PAHs) Compound-specific delta C-13 Paleofire Experimental biomass burning CARBON ISOTOPIC COMPOSITION MOLECULAR TRACERS ORGANIC-COMPOUNDS PYROGENIC CARBON EMISSION FACTORS SOURCE IDENTIFICATION CHEMICAL-COMPOSITION LAKE-SEDIMENTS BIOMASS CHARCOAL Polycyclic aromatic hydrocarbons (PAHs), produced via incomplete combustion of organics, convey signatures of vegetation burned in the geologic past. New and published burn experiments reveal how the quantity, distributions, and isotopic abundances of fire-derived PAHs were influenced by fuel types, burn conditions, and also phase. PAH concentrations were higher in burn residues from moderate burn temperatures (400–500 °C), and significantly lower in residues from cooler (<300 °C) or hotter (>600 °C) conditions, especially when oxygen was limited. PAH forms tended to be smaller in smoke samples and larger in residues, consistent with molecular physical and chemical properties. Plant functional types were distinguished by relative amounts of retene and dimethyl phenanthrene isomers. Isotopically distinct photosynthetic pathways of the burned material were reflected in the δ13C values of PAHs, which faithfully captured biomass signatures as well as the ∼12‰ offset between C3 and C4 plant types. PAH size, alkylation, and isotope characteristics can differentiate combusted plant types and distinguish between air-borne and sedimentary transport mechanisms. New proxy approaches using PAH amounts, distributions, and isotope signatures can aid and refine interpretations of paleofire ecology in the geologic record. 2020 Journal Article http://hdl.handle.net/20.500.11937/90114 10.1016/j.gca.2020.08.024 English http://purl.org/au-research/grants/arc/DP130100577 http://purl.org/au-research/grants/arc/LE110100119 http://creativecommons.org/licenses/by-nc-nd/4.0/ PERGAMON-ELSEVIER SCIENCE LTD fulltext |
| spellingShingle | Science & Technology Physical Sciences Geochemistry & Geophysics Polycyclic aromatic hydrocarbons (PAHs) Compound-specific delta C-13 Paleofire Experimental biomass burning CARBON ISOTOPIC COMPOSITION MOLECULAR TRACERS ORGANIC-COMPOUNDS PYROGENIC CARBON EMISSION FACTORS SOURCE IDENTIFICATION CHEMICAL-COMPOSITION LAKE-SEDIMENTS BIOMASS CHARCOAL Karp, A.T. Holman, Alex Hopper, Peter Grice, Kliti Freeman, K.H. Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title | Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title_full | Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title_fullStr | Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title_full_unstemmed | Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title_short | Fire distinguishers: Refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| title_sort | fire distinguishers: refined interpretations of polycyclic aromatic hydrocarbons for paleo-applications |
| topic | Science & Technology Physical Sciences Geochemistry & Geophysics Polycyclic aromatic hydrocarbons (PAHs) Compound-specific delta C-13 Paleofire Experimental biomass burning CARBON ISOTOPIC COMPOSITION MOLECULAR TRACERS ORGANIC-COMPOUNDS PYROGENIC CARBON EMISSION FACTORS SOURCE IDENTIFICATION CHEMICAL-COMPOSITION LAKE-SEDIMENTS BIOMASS CHARCOAL |
| url | http://purl.org/au-research/grants/arc/DP130100577 http://purl.org/au-research/grants/arc/DP130100577 http://hdl.handle.net/20.500.11937/90114 |