|
Titel |
Polar organic tracers in PM2.5 aerosols from forests in eastern China |
VerfasserIn |
W. Wang, M. H. Wu, L. Li, T. Zhang, X. D. Liu, J. L. Feng, H. J. Li, Y. J. Wang, G. Y. Sheng, M. Claeys, J. M. Fu |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1680-7316
|
Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 8, no. 24 ; Nr. 8, no. 24 (2008-12-16), S.7507-7518 |
Datensatznummer |
250006514
|
Publikation (Nr.) |
copernicus.org/acp-8-7507-2008.pdf |
|
|
|
Zusammenfassung |
Photooxidation products of biogenic volatile organic compounds, mainly
isoprene and monoterpenes, are significant sources of atmospheric
particulate matter in forested regions. The objectives of this study were to
examine time series and diel variations of polar organic tracers for the
photooxidation of isoprene and α-pinene to investigate whether they
are linked with meteorological parameters or trace gases, and to determine
their carbon contributions. In addition, the biogenic
secondary organic carbon contributions from isoprene were estimated.
PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm)
aerosol samples were collected from forests in eastern China and compared
with data from forested sites in Europe and America. Aerosol sampling was
conducted at four sites located along a gradient of ecological succession in
four different regions, i.e. Changbai Mountain Nature Reserve
(boreal-temperate), Chongming National Forest Park (temperate), Dinghu
Mountain Nature Reserve (subtropical) and Jianfengling Nature Reserve in
Hainan (tropical) during summer periods when the meteorological conditions
are believed to be favorable for photochemical processes. Fifty PM2.5
samples were collected; eighteen organic compounds, organic
carbon (OC), elemental carbon and trace gases were measured. Results
indicate that the concentration trends of the secondary organic compounds
reflected those of the trace gases and meteorological parameters. Very good
correlations between the sum concentrations of isoprene oxidation products
and atmospheric SO2, O3, NO2, NOx, as well as CO2,
at the Changbai site were found. The secondary OC due to isoprene was
relatively high in tropical Hainan (0.27 μgC/m3) where
isoprene-emitting broadleaf species are dominant, but was comparable in
boreal Changbai (0.32 μgC/m3) where coniferous species are
prevalent. The contribution of malic acid, which may have both biogenic and
anthropogenic sources, to the OC mass was comparable at the four sites. |
|
|
Teil von |
|
|
|
|
|
|