Factors influencing the stable carbon isotopic signature of methane from combustion and biomass burning

Abstract. Organic tracer compounds of tropospheric aerosols, as well as organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), and stable carbon isotope ratios (δ13C) of total carbon (TC) have been investigated for aerosol samples collected during early and late periods of Mount Tai eXperiment 2006 (MTX2006) field campaign in North China Plain. Total solvent extracts were investigated by gas chromatography/mass spectrometry. More than 130 organic compounds were detected in the aerosol samples. They were grouped into twelve organic compound classes, including biomass burning tracers, biogenic primary sugars, biogenic secondary organic aerosol (SOA) tracers, and anthropogenic tracers such as phthalates, hopanes and polycyclic aromatic hydrocarbons (PAHs). In early June when the field burning activities of wheat straws in North China Plain were very active, the total identified organics (2090 ± 1170 ng m−3) were double those in late June (926 ± 574 ng m−3). All the compound classes were more abundant in early June than in late June, except phthalate esters, which were higher in late June. Levoglucosan (88–1210 ng m−3, 403 ng m−3) was found as the most abundant single compound in early June, while diisobutyl phthalate was the predominant species in late June. During the biomass-burning period in early June, the diurnal trends of most of the primary and secondary organic aerosol tracers were characterized by the concentration peaks observed at mid-night or in early morning, while in late June most of the organic species peaked in late afternoon. This suggests that smoke plumes from biomass burning can uplift the aerosol particulate matter to a certain altitude and then transported to and encountered the summit of Mt. Tai during nighttime. On the basis of the tracer-based method for the estimation of biomass-burning OC, fungal-spore OC and biogenic secondary organic carbon (SOC), we estimate that an average of 24% (up to 64%) of the OC in the Mt. Tai aerosols was due to biomass burning in early June, followed by the contribution of isoprene SOC (mean 4.3%). In contrast, isoprene SOC was the main contributor (6.6%) to OC, and only 3.0% of the OC was due to biomass burning in late June. In early June, δ13C of TC (−26.6‰ to −23.2‰, mean −25.0‰) were lower than those (−23.9‰ to −21.9‰, mean −22.9‰) in late June. In addition, a strong anti-correlation was found between levoglucosan and δ13C values. This study demonstrates that crop-residue burning activities can significantly enhance the organic aerosol loading and alter the organic molecular compositions and stable carbon isotopic compositions of aerosol particles in the troposphere over North China Plain.

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Diurnal variations of organic molecular tracers and stable carbon isotopic composition in atmospheric aerosols over Mt. Tai in the North China Plain: an influence of biomass burning

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-8359-2012 ◽

2012 ◽

Vol 12 (18) ◽

pp. 8359-8375 ◽

Cited By ~ 87

Author(s):

P. Q. Fu ◽

K. Kawamura ◽

J. Chen ◽

J. Li ◽

Y. L. Sun ◽

...

Keyword(s):

Organic Carbon ◽

Biomass Burning ◽

North China Plain ◽

North China ◽

Carbon Isotopic Composition ◽

Organic Aerosol ◽

Stable Carbon ◽

Carbon Isotopic ◽

The North ◽

The North China Plain

Abstract. Organic tracer compounds, as well as organic carbon (OC), elemental carbon (EC), water-soluble organic carbon (WSOC), and stable carbon isotope ratios (δ13C) of total carbon (TC) have been investigated in aerosol samples collected during early and late periods of the Mount Tai eXperiment 2006 (MTX2006) field campaign in the North China Plain. Total solvent-extractable fractions were investigated by gas chromatography/mass spectrometry. More than 130 organic compounds were detected in the aerosol samples. They were grouped into twelve organic compound classes, including biomass burning tracers, biogenic primary sugars, biogenic secondary organic aerosol (SOA) tracers, and anthropogenic tracers such as phthalates, hopanes and polycyclic aromatic hydrocarbons (PAHs). In early June when the field burning activities of wheat straws in the North China Plain were very active, the total identified organics (2090 ± 1170 ng m−3) were double those in late June (926 ± 574 ng m−3). All the compound classes were more abundant in early June than in late June, except phthalate esters, which were higher in late June. Levoglucosan (88–1210 ng m−3, mean 403 ng m−3) was found as the most abundant single compound in early June, while diisobutyl phthalate was the predominant species in late June. During the biomass-burning period in early June, the diurnal trends of most of the primary and secondary organic aerosol tracers were characterized by the concentration peaks observed at mid-night or in early morning, while in late June most of the organic species peaked in late afternoon. This suggests that smoke plumes from biomass burning can uplift the aerosol particulate matter to a certain altitude, which could be further transported to and encountered the summit of Mt. Tai during nighttime. On the basis of the tracer-based method for the estimation of biomass-burning OC, fungal-spore OC and biogenic secondary organic carbon (SOC), we estimate that an average of 24% (up to 64%) of the OC in the Mt. Tai aerosols was due to biomass burning in early June, followed by the contribution of isoprene SOC (mean 4.3%). In contrast, isoprene SOC was the main contributor (6.6%) to OC, and only 3.0% of the OC was due to biomass burning in late June. In early June, δ13C of TC (−26.6 to −23.2‰, mean −25.0‰) were lower than those (−23.9 to −21.9‰, mean −22.9‰) in late June. In addition, a strong anti-correlation was found between levoglucosan and δ13C values. This study demonstrates that crop-residue burning activities can significantly enhance the organic aerosol loading and alter the organic composition and stable carbon isotopic composition of aerosol particles in the troposphere over the North China Plain.

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Variability of stable carbon isotopic compositions in individual fatty acids from combustion of C4 and C3 plants: implications for biomass burning

Chemical Geology ◽

10.1016/s0009-2541(98)00103-x ◽

1998 ◽

Vol 152 (1-2) ◽

pp. 151-161 ◽

Cited By ~ 70

Author(s):

Donna C. Ballentine ◽

Stephen A. Macko ◽

Vaughan C. Turekian

Keyword(s):

Fatty Acids ◽

Biomass Burning ◽

C3 Plants ◽

Stable Carbon ◽

Isotopic Compositions ◽

Carbon Isotopic

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Molecular distribution and compound-specific stable carbon isotopic composition of dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls in PM<sub>2.5</sub> from Beijing, China

10.5194/acp-2017-410 ◽

2017 ◽

Author(s):

Wanyu Zhao ◽

Kimitaka Kawamura ◽

Siyao Yue ◽

Lianfang Wei ◽

Hong Ren ◽

...

Keyword(s):

Isotopic Composition ◽

Succinic Acid ◽

Biomass Burning ◽

Fossil Fuel ◽

Carbon Isotopic Composition ◽

Dicarboxylic Acids ◽

Fossil Fuel Combustion ◽

Stable Carbon ◽

Carbon Isotopic ◽

Oxocarboxylic Acids

Abstract. This study investigates the seasonal variation, molecular distribution and stable carbon isotopic composition of diacids, oxocarboxylic acids and α-dicarbonyls to better understand the sources and formation processes of fine aerosols (PM2.5) in Beijing. The concentrations of total dicarboxylic acids varied from 110 to 2580 ng m−3, whereas oxoacids (9.50–353 ng m−3) and dicarbonyls (1.50–85.9 ng m−3) were less abundant. Oxalic acid was found to be the most abundant individual species, followed by succinic acid or occasionally by terephthalic acid (tPh), a plastic burning tracer. Ambient concentrations of phthalic acid (37.9±27.3 ng m−3) and tPh (48.7±51.1 ng m−3) are larger in winter than in other seasons, illustrating that fossil fuel combustion and plastic waste incineration contribute more significantly to wintertime aerosols. The year-round mass concentration ratios of malonic acid to succinic acid (C3/C4) are relatively by comparison with those in other urban aerosols and remote marine aerosols, most of which are less than or equal to unity in Beijing; thus, the degree of photochemical formation of diacids in Beijing is insignificant. Moreover, positive correlations of some oxocarboxylic acids and α-dicarbonyls with nss-K+, a tracer for biomass burning, suggest biogenic combustion activities accounting for a large contribution of these organic acids and related precursors. The mean δ13C value of succinic acid is highest among all species with values of −17.1±3.9‰ (winter) and −17.1±2.0‰ (spring), while malonic acid is less enriched in 13C than others in autumn (−17.6±4.6‰) and summer (−18.7±4.0‰). The δ13C values of major species in the Beijing aerosols are generally lower with a wider range than those in downwind regions in the western North Pacific, which indicates that Beijing has diverse emission sources with weak photooxidation. Thus, our study demonstrates that in addition to photochemical oxidation, high abundances of diacids, oxocarboxylic acids and α-dicarbonyls in Beijing are largely associated with anthropogenic primary emissions, such as biomass burning, fossil fuel combustion, and plastic burning.

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