Title data
Stella, Patrick ; Kortner, Michael ; Ammann, Christof ; Foken, Thomas ; Meixner, Franz X. ; Trebs, Ivonne:
Measurements of nitrogen oxides and ozone fluxes by eddy covariance at a meadow: evidence for an internal leaf resistance to NO2.
In: Biogeosciences Discussions.
Vol. 10
(2013)
.
- pp. 4461-4514.
ISSN 1810-6285
DOI: https://doi.org/10.5194/bgd-10-4461-2013
Abstract in another language
Nitrogen dioxide (NO2) plays an important role in atmospheric pollution, in particular for tropospheric ozone production. However, the removal processes involved in NO2 deposition to terrestrial ecosystems are still subject of ongoing discussion. This study reports NO2 flux measurements made over a meadow using the eddy covariance method. The measured NO2 deposition fluxes during daytime were about a factor of two lower than a priori calculated fluxes using the Surfatm model without taking into account an internal (also called mesophyllic or sub-stomatal) resistance. Neither an underestimation of the measured NO2 deposition flux due to chemical divergence or direct NO2 emission, nor an underestimation of the resistances used to model the NO2 deposition explained the large difference between measured and modelled NO2 fluxes. Thus, only the existence of the internal resistance could account for this large discrepancy between model and measurements. The median internal resistance was estimated to 300 s m−1 during daytime, but exhibited a large variability (100 s m−1 to 800 s m−1). In comparison, the stomatal resistance was only around 100 s m−1 during daytime. Hence, the internal resistance accounted for 50% to 90% of the total leaf resistance to NO2. This study presents the first clear evidence and quantification of the internal resistance using the eddy covariance method, i.e. plant functioning was not affected by changes of microclimatological (turbulent) conditions that typically occur when using enclosure methods.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | No |
Additional notes: | BAYCEER114352 |
Institutions of the University: | Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences > Professor Micrometeorology Research Institutions > Central research institutes > Bayreuth Center of Ecology and Environmental Research- BayCEER Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Earth Sciences Research Institutions Research Institutions > Central research institutes |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science |
Date Deposited: | 18 May 2015 09:01 |
Last Modified: | 14 Apr 2018 02:48 |
URI: | https://eref.uni-bayreuth.de/id/eprint/13862 |