Seasonal characteristics of biogenic secondary organic aerosol tracers in a deciduous broadleaf forest in northern Japan

Md Mozammel Haque; Santosh Kumar Verma; Dhananjay K Deshmukh; Bhagawati Kunwar; Kimitaka Kawamura

doi:10.1016/j.chemosphere.2022.136785

Seasonal characteristics of biogenic secondary organic aerosol tracers in a deciduous broadleaf forest in northern Japan

Chemosphere. 2023 Jan;311(Pt 1):136785. doi: 10.1016/j.chemosphere.2022.136785. Epub 2022 Oct 15.

Authors

Md Mozammel Haque¹, Santosh Kumar Verma², Dhananjay K Deshmukh³, Bhagawati Kunwar⁴, Kimitaka Kawamura⁵

Affiliations

¹ Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change (ILCEC), Nanjing University of Information Science & Technology, Nanjing, 210044, China; School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China; Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan. Electronic address: mhaque@nuist.edu.cn.
² Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan; State Forensic Science Laboratory, Home Department, Government of Chhattisgarh, Raipur, 492-001, India.
³ Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram, 695-002, India; Chubu Institute for Advanced Studies, Chubu University, Kasugai, 487-8501, Japan.
⁴ Chubu Institute for Advanced Studies, Chubu University, Kasugai, 487-8501, Japan.
⁵ Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan; Chubu Institute for Advanced Studies, Chubu University, Kasugai, 487-8501, Japan. Electronic address: kkawamura@isc.chubu.ac.jp.

PMID: 36257396
DOI: 10.1016/j.chemosphere.2022.136785

Abstract

We collected total suspended particulate (TSP) samples from January 2010 to December 2010 at Sapporo deciduous forest to understand the oxidation processes of biogenic volatile organic compounds (BVOCs). The gas chromatography-mass spectrometric technique was applied to determine biogenic secondary organic aerosols (BSOAs) in the TSP samples. We found the predominance of the isoprene SOA (iSOA) tracers (20.6 ng m^-3) followed by α/β-pinene SOA (pSOA) tracers (8.25 ng m^-3) and β-caryophyllene SOA (cSOA) tracer (1.53 ng m^-3) in the forest aerosols. The results showed large isoprene fluxes and relatively high levels of oxidants in the forest atmosphere. The iSOA and pSOA tracers showed a clear seasonal trend with summer and autumn maxima and winter and spring minima. Their seasonal trends were mainly controlled by BVOCs emission from the local broadleaf deciduous forest. Additionally, the regional level of isoprene emissions from the oceanic sources may also be contributed during summertime aerosols. cSOA tracer showed high concentrations in the winter and spring, possibly due to an additional contribution of biomass burning (BB) aerosols from the local or regional BB activities. The biogenic secondary organic carbon (BSOC) was contributed mainly by the oxidation products of isoprene (136 ngC m^-³) followed by β-caryophyllene (63.0 ngC m^-3) and α/β-pinene (35.9 ngC m^-3). The mass concentration ratio (0.92) of pinonic acid + pinic acid and 3-methyl-1,2,3-butanetricarboxylic acid ((PNA + PA)/3-MBTCA) indicates the photochemical transformation of first-generation oxidation products to the higher generation oxidation products. The average ratios of isoprene to α/β-pinene (1.64) and β-caryophyllene (18.6) oxidation products suggested a large difference in the emissions of isoprene and α/β-pinene compared to β-caryophyllene. The cSOA tracers in the forest aerosols are also contributed by BB during the winter and spring. Positive matrix factorization analyses of the BSOA tracers confirmed that organic aerosols of deciduous forests are mostly related to isoprene emissions. This study suggests that isoprene is a more significant precursor for the BSOA than α/β-pinene and β-caryophyllene in a broadleaf deciduous forest.

Keywords: Biogenic emissions; Biogenic secondary organic aerosols; Deciduous forest; Isoprene abundance.

MeSH terms

Aerosols / analysis
Air Pollutants* / analysis
Forests
Japan
Seasons
Volatile Organic Compounds* / analysis

Substances

isoprene
beta-pinene
caryophyllene
Air Pollutants
Aerosols
alpha-pinene
Volatile Organic Compounds