Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland
<p>The exchange ratio (ER) between atmospheric <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> is a useful tracer for better understanding the carbon budget on global an...
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2023-01-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/23/851/2023/acp-23-851-2023.pdf |
| _version_ | 1828059228385837056 |
|---|---|
| author | K. A. P. Faassen L. N. T. Nguyen E. R. Broekema B. A. M. Kers I. Mammarella T. Vesala T. Vesala P. A. Pickers A. C. Manning J. Vilà-Guerau de Arellano J. Vilà-Guerau de Arellano H. A. J. Meijer W. Peters W. Peters I. T. Luijkx |
| author_facet | K. A. P. Faassen L. N. T. Nguyen E. R. Broekema B. A. M. Kers I. Mammarella T. Vesala T. Vesala P. A. Pickers A. C. Manning J. Vilà-Guerau de Arellano J. Vilà-Guerau de Arellano H. A. J. Meijer W. Peters W. Peters I. T. Luijkx |
| author_sort | K. A. P. Faassen |
| collection | DOAJ |
| description | <p>The exchange ratio (ER) between atmospheric <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> is a useful tracer for better understanding the carbon budget on global and
local scales. The variability of ER (in <span class="inline-formula">mol O<sub>2</sub> per mol CO<sub>2</sub></span>) between terrestrial ecosystems is not well known, and there is no consensus on how to derive
the ER signal of an ecosystem, as there are different approaches available, either based on concentration (<span class="inline-formula">ER<sub>atmos</sub></span>) or flux measurements
(<span class="inline-formula">ER<sub>forest</sub></span>). In this study we measured atmospheric <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> concentrations at two heights (23 and 125 <span class="inline-formula">m</span>) above
the boreal forest in Hyytiälä, Finland. Such measurements of <span class="inline-formula">O<sub>2</sub></span> are unique and enable us to potentially identify which forest carbon
loss and production mechanisms dominate over various hours of the day. We found that the <span class="inline-formula">ER<sub>atmos</sub></span> signal at 23 <span class="inline-formula">m</span> not only represents the diurnal cycle of the forest exchange but also includes other factors, including entrainment of air masses in the atmospheric boundary layer before midday, with different thermodynamic and atmospheric composition characteristics. To derive <span class="inline-formula">ER<sub>forest</sub></span>, we infer <span class="inline-formula">O<sub>2</sub></span> fluxes
using multiple theoretical and observation-based micro-meteorological formulations to determine the most suitable approach. Our resulting
<span class="inline-formula">ER<sub>forest</sub></span> shows a distinct difference in behaviour between daytime (0.92 <span class="inline-formula">±</span> 0.17 <span class="inline-formula">mol mol<sup>−1</sup></span>) and nighttime
(1.03 <span class="inline-formula">±</span> 0.05 <span class="inline-formula">mol mol<sup>−1</sup></span>). These insights demonstrate the diurnal variability of different ER signals above a boreal forest, and we
also confirmed that the signals of <span class="inline-formula">ER<sub>atmos</sub></span> and <span class="inline-formula">ER<sub>forest</sub></span> cannot be used interchangeably. Therefore, we recommend measurements on
multiple vertical levels to derive <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> fluxes for the <span class="inline-formula">ER<sub>forest</sub></span> signal instead of a single level time series of the
concentrations for the <span class="inline-formula">ER<sub>atmos</sub></span> signal. We show that <span class="inline-formula">ER<sub>forest</sub></span> can be further split into specific signals for respiration
(1.03 <span class="inline-formula">±</span> 0.05 <span class="inline-formula">mol mol<sup>−1</sup></span>) and photosynthesis (0.96 <span class="inline-formula">±</span> 0.12 <span class="inline-formula">mol mol<sup>−1</sup></span>). This estimation allows us to separate the
net ecosystem exchange (NEE) into gross primary production (GPP) and total ecosystem respiration (TER), giving comparable results to the more
commonly used eddy covariance approach. Our study shows the potential of using atmospheric <span class="inline-formula">O<sub>2</sub></span> as an alternative and complementary method to
gain new insights into the different <span class="inline-formula">CO<sub>2</sub></span> signals that contribute to the forest carbon budget.</p> |
| first_indexed | 2024-04-10T21:38:46Z |
| format | Article |
| id | doaj.art-07cb97a9b1224faa9cd34219330805e2 |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-04-10T21:38:46Z |
| publishDate | 2023-01-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-07cb97a9b1224faa9cd34219330805e22023-01-19T06:27:09ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242023-01-012385187610.5194/acp-23-851-2023Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern FinlandK. A. P. Faassen0L. N. T. Nguyen1E. R. Broekema2B. A. M. Kers3I. Mammarella4T. Vesala5T. Vesala6P. A. Pickers7A. C. Manning8J. Vilà-Guerau de Arellano9J. Vilà-Guerau de Arellano10H. A. J. Meijer11W. Peters12W. Peters13I. T. Luijkx14Meteorology and Air Quality, Wageningen University and Research, Wageningen, the NetherlandsCentre for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, the NetherlandsCentre for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, the NetherlandsCentre for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, the NetherlandsInstitute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, Helsinki, FinlandInstitute for Atmospheric and Earth System Research (INAR)/Physics, Faculty of Science, University of Helsinki, Helsinki, FinlandINAR/Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, FinlandCentre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, United KingdomCentre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, United KingdomMeteorology and Air Quality, Wageningen University and Research, Wageningen, the NetherlandsAtmospheric Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, GermanyCentre for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, the NetherlandsMeteorology and Air Quality, Wageningen University and Research, Wageningen, the NetherlandsCentre for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, the NetherlandsMeteorology and Air Quality, Wageningen University and Research, Wageningen, the Netherlands<p>The exchange ratio (ER) between atmospheric <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> is a useful tracer for better understanding the carbon budget on global and local scales. The variability of ER (in <span class="inline-formula">mol O<sub>2</sub> per mol CO<sub>2</sub></span>) between terrestrial ecosystems is not well known, and there is no consensus on how to derive the ER signal of an ecosystem, as there are different approaches available, either based on concentration (<span class="inline-formula">ER<sub>atmos</sub></span>) or flux measurements (<span class="inline-formula">ER<sub>forest</sub></span>). In this study we measured atmospheric <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> concentrations at two heights (23 and 125 <span class="inline-formula">m</span>) above the boreal forest in Hyytiälä, Finland. Such measurements of <span class="inline-formula">O<sub>2</sub></span> are unique and enable us to potentially identify which forest carbon loss and production mechanisms dominate over various hours of the day. We found that the <span class="inline-formula">ER<sub>atmos</sub></span> signal at 23 <span class="inline-formula">m</span> not only represents the diurnal cycle of the forest exchange but also includes other factors, including entrainment of air masses in the atmospheric boundary layer before midday, with different thermodynamic and atmospheric composition characteristics. To derive <span class="inline-formula">ER<sub>forest</sub></span>, we infer <span class="inline-formula">O<sub>2</sub></span> fluxes using multiple theoretical and observation-based micro-meteorological formulations to determine the most suitable approach. Our resulting <span class="inline-formula">ER<sub>forest</sub></span> shows a distinct difference in behaviour between daytime (0.92 <span class="inline-formula">±</span> 0.17 <span class="inline-formula">mol mol<sup>−1</sup></span>) and nighttime (1.03 <span class="inline-formula">±</span> 0.05 <span class="inline-formula">mol mol<sup>−1</sup></span>). These insights demonstrate the diurnal variability of different ER signals above a boreal forest, and we also confirmed that the signals of <span class="inline-formula">ER<sub>atmos</sub></span> and <span class="inline-formula">ER<sub>forest</sub></span> cannot be used interchangeably. Therefore, we recommend measurements on multiple vertical levels to derive <span class="inline-formula">O<sub>2</sub></span> and <span class="inline-formula">CO<sub>2</sub></span> fluxes for the <span class="inline-formula">ER<sub>forest</sub></span> signal instead of a single level time series of the concentrations for the <span class="inline-formula">ER<sub>atmos</sub></span> signal. We show that <span class="inline-formula">ER<sub>forest</sub></span> can be further split into specific signals for respiration (1.03 <span class="inline-formula">±</span> 0.05 <span class="inline-formula">mol mol<sup>−1</sup></span>) and photosynthesis (0.96 <span class="inline-formula">±</span> 0.12 <span class="inline-formula">mol mol<sup>−1</sup></span>). This estimation allows us to separate the net ecosystem exchange (NEE) into gross primary production (GPP) and total ecosystem respiration (TER), giving comparable results to the more commonly used eddy covariance approach. Our study shows the potential of using atmospheric <span class="inline-formula">O<sub>2</sub></span> as an alternative and complementary method to gain new insights into the different <span class="inline-formula">CO<sub>2</sub></span> signals that contribute to the forest carbon budget.</p>https://acp.copernicus.org/articles/23/851/2023/acp-23-851-2023.pdf |
| spellingShingle | K. A. P. Faassen L. N. T. Nguyen E. R. Broekema B. A. M. Kers I. Mammarella T. Vesala T. Vesala P. A. Pickers A. C. Manning J. Vilà-Guerau de Arellano J. Vilà-Guerau de Arellano H. A. J. Meijer W. Peters W. Peters I. T. Luijkx Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland Atmospheric Chemistry and Physics |
| title | Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland |
| title_full | Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland |
| title_fullStr | Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland |
| title_full_unstemmed | Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland |
| title_short | Diurnal variability of atmospheric O<sub>2</sub>, CO<sub>2</sub>, and their exchange ratio above a boreal forest in southern Finland |
| title_sort | diurnal variability of atmospheric o sub 2 sub co sub 2 sub and their exchange ratio above a boreal forest in southern finland |
| url | https://acp.copernicus.org/articles/23/851/2023/acp-23-851-2023.pdf |
| work_keys_str_mv | AT kapfaassen diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT lntnguyen diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT erbroekema diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT bamkers diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT imammarella diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT tvesala diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT tvesala diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT papickers diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT acmanning diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT jvilagueraudearellano diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT jvilagueraudearellano diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT hajmeijer diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT wpeters diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT wpeters diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland AT itluijkx diurnalvariabilityofatmosphericosub2subcosub2subandtheirexchangeratioaboveaborealforestinsouthernfinland |