PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest
<p>Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution to atmospheric chemistry and biogeochemical cycles. Tropical forests are the largest source of the dominant BVOC emissions (e.g. isoprene and monoterpenes). In this study, we rep...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2020-06-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/20/7179/2020/acp-20-7179-2020.pdf |
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doaj-12c15e3c979441b68c0afb7b82758e45 |
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Article |
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DOAJ |
| language |
English |
| format |
Article |
| sources |
DOAJ |
| author |
C. Sarkar A. B. Guenther J.-H. Park R. Seco R. Seco E. Alves E. Alves S. Batalha R. Santana S. Kim J. Smith J. Tóta O. Vega |
| spellingShingle |
C. Sarkar A. B. Guenther J.-H. Park R. Seco R. Seco E. Alves E. Alves S. Batalha R. Santana S. Kim J. Smith J. Tóta O. Vega PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest Atmospheric Chemistry and Physics |
| author_facet |
C. Sarkar A. B. Guenther J.-H. Park R. Seco R. Seco E. Alves E. Alves S. Batalha R. Santana S. Kim J. Smith J. Tóta O. Vega |
| author_sort |
C. Sarkar |
| title |
PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest |
| title_short |
PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest |
| title_full |
PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest |
| title_fullStr |
PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest |
| title_full_unstemmed |
PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforest |
| title_sort |
ptr-tof-ms eddy covariance measurements of isoprene and monoterpene fluxes from an eastern amazonian rainforest |
| publisher |
Copernicus Publications |
| series |
Atmospheric Chemistry and Physics |
| issn |
1680-7316 1680-7324 |
| publishDate |
2020-06-01 |
| description |
<p>Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution to atmospheric chemistry and biogeochemical cycles. Tropical forests are the largest source of the dominant BVOC emissions (e.g. isoprene and monoterpenes). In this study, we report isoprene and total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using the eddy covariance (EC) method at the Tapajós National Forest (2.857<span class="inline-formula"><sup>∘</sup></span> S, 54.959<span class="inline-formula"><sup>∘</sup></span> W), a primary rainforest in eastern Amazonia. Measurements were carried out from 1 to 16 June 2014, during the wet-to-dry transition season. During the measurement period, the measured daytime (06:00–18:00 LT) average isoprene mixing ratios and fluxes were <span class="inline-formula">1.15±0.60</span> ppb and <span class="inline-formula">0.55±0.71</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively, whereas the measured daytime average total monoterpene mixing ratios and fluxes were <span class="inline-formula">0.14±0.10</span> ppb and <span class="inline-formula">0.20±0.25</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively. Midday (10:00–14:00 LT) average isoprene and total monoterpene mixing ratios were <span class="inline-formula">1.70±0.49</span> and <span class="inline-formula">0.24±0.05</span> ppb, respectively, whereas midday average isoprene and monoterpene fluxes were <span class="inline-formula">1.24±0.68</span> and <span class="inline-formula">0.46±0.22</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively. Isoprene and total monoterpene emissions in Tapajós were correlated with ambient temperature and solar radiation. Significant correlation with sensible heat flux, SHF (<span class="inline-formula"><i>r</i><sup>2</sup>=0.77</span>), was also observed. Measured isoprene and monoterpene fluxes were strongly correlated with each other (<span class="inline-formula"><i>r</i><sup>2</sup>=0.93</span>). The MEGAN2.1 (Model of Emissions of Gases and Aerosols from Nature version 2.1) model could simulate most of the observed diurnal variations (<span class="inline-formula"><i>r</i><sup>2</sup>=0.7</span> to 0.8) but declined a little later in the evening for both isoprene and total monoterpene fluxes. The results also demonstrate the importance of site-specific vegetation emission factors (EFs) for accurately simulating BVOC fluxes in regional and global BVOC emission models.</p> |
| url |
https://www.atmos-chem-phys.net/20/7179/2020/acp-20-7179-2020.pdf |
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doaj-12c15e3c979441b68c0afb7b82758e452020-11-25T03:20:16ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242020-06-01207179719110.5194/acp-20-7179-2020PTR-TOF-MS eddy covariance measurements of isoprene and monoterpene fluxes from an eastern Amazonian rainforestC. Sarkar0A. B. Guenther1J.-H. Park2R. Seco3R. Seco4E. Alves5E. Alves6S. Batalha7R. Santana8S. Kim9J. Smith10J. Tóta11O. Vega12Department of Earth System Science, University of California, Irvine, California 92697, USADepartment of Earth System Science, University of California, Irvine, California 92697, USAClimate and Air Quality Research Department, National Institute of Environmental Research (NIER), Incheon, 22689, Republic of KoreaTerrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, DenmarkCenter for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, DenmarkDepartment of Climate and Environment, National Institute for Amazonian Research, Manaus, 69067-375, Amazonas, Brazilnow at: Department of Biogeochemical Processes, Max Planck Institute for Biogeochemistry, 07745 Jena, GermanyCentro Universitário da Amazônia, Universidade da Amazônia, UNAMA, Santarém, 68010-200, Pará, BrazilInstituto de Engenharia e Geociências, Universidade Federal do Oeste do Pará, Santarém, 68040-255, Pará, BrazilDepartment of Earth System Science, University of California, Irvine, California 92697, USADepartment of Chemistry, University of California, Irvine, California 92697, USAInstituto de Engenharia e Geociências, Universidade Federal do Oeste do Pará, Santarém, 68040-255, Pará, BrazilCentro de Química e Meio Ambiente, Instituto de Pesquisas Energéticas e Nucleares, São Paulo, 05508-000, Brazil<p>Biogenic volatile organic compounds (BVOCs) are important components of the atmosphere due to their contribution to atmospheric chemistry and biogeochemical cycles. Tropical forests are the largest source of the dominant BVOC emissions (e.g. isoprene and monoterpenes). In this study, we report isoprene and total monoterpene flux measurements with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) using the eddy covariance (EC) method at the Tapajós National Forest (2.857<span class="inline-formula"><sup>∘</sup></span> S, 54.959<span class="inline-formula"><sup>∘</sup></span> W), a primary rainforest in eastern Amazonia. Measurements were carried out from 1 to 16 June 2014, during the wet-to-dry transition season. During the measurement period, the measured daytime (06:00–18:00 LT) average isoprene mixing ratios and fluxes were <span class="inline-formula">1.15±0.60</span> ppb and <span class="inline-formula">0.55±0.71</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively, whereas the measured daytime average total monoterpene mixing ratios and fluxes were <span class="inline-formula">0.14±0.10</span> ppb and <span class="inline-formula">0.20±0.25</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively. Midday (10:00–14:00 LT) average isoprene and total monoterpene mixing ratios were <span class="inline-formula">1.70±0.49</span> and <span class="inline-formula">0.24±0.05</span> ppb, respectively, whereas midday average isoprene and monoterpene fluxes were <span class="inline-formula">1.24±0.68</span> and <span class="inline-formula">0.46±0.22</span> mg C m<span class="inline-formula"><sup>−2</sup></span> h<span class="inline-formula"><sup>−1</sup></span>, respectively. Isoprene and total monoterpene emissions in Tapajós were correlated with ambient temperature and solar radiation. Significant correlation with sensible heat flux, SHF (<span class="inline-formula"><i>r</i><sup>2</sup>=0.77</span>), was also observed. Measured isoprene and monoterpene fluxes were strongly correlated with each other (<span class="inline-formula"><i>r</i><sup>2</sup>=0.93</span>). The MEGAN2.1 (Model of Emissions of Gases and Aerosols from Nature version 2.1) model could simulate most of the observed diurnal variations (<span class="inline-formula"><i>r</i><sup>2</sup>=0.7</span> to 0.8) but declined a little later in the evening for both isoprene and total monoterpene fluxes. The results also demonstrate the importance of site-specific vegetation emission factors (EFs) for accurately simulating BVOC fluxes in regional and global BVOC emission models.</p>https://www.atmos-chem-phys.net/20/7179/2020/acp-20-7179-2020.pdf |