Articles | Volume 22, issue 21
https://doi.org/10.5194/bg-22-6669-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-6669-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Nov 2025
Research article |
| 10 Nov 2025
| 10 Nov 2025
Aerodynamic flux–gradient measurements of ammonia over four spring seasons in grazed grassland: environmental drivers, methodological challenges and uncertainties
Mubaraq Olarewaju Abdulwahab
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Christophe Flechard
CORRESPONDING AUTHOR
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Yannick Fauvel
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Christoph Häni
School of Agricultural, Forest and Food Sciences HAFL, Bern University of Applied Sciences, Zollikofen, 3052, Switzerland
Adrien Jacotot
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Chrono-Environnement, UMR 6249, Université Marie et Louis Pasteur, CNRS, 25000 Besançon, France
SARL SEMBIOSE, 53500 Saint-Denis-de-Gastines, France
Anne-Isabelle Graux
UMR PEGASE, INRAE, Institut Agro, Saint-Gilles, 35590, France
Nadège Edouard
UMR PEGASE, INRAE, Institut Agro, Saint-Gilles, 35590, France
Pauline Buysse
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Valérie Viaud
UMR 1069 SAS, INRAE, Institut Agro, Rennes, 35042, France
Albrecht Neftel
Neftel Research Expertise, Wohlen b. Bern, 3033, Switzerland
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Short summary
Pastures are an important source of ammonia, a major atmospheric pollutant with manifold environmental impacts. Ammonia is emitted from the decomposition of cattle urine in soils during grazing. We used micrometeorological methods to measure emissions over four grazing seasons. The results show the influence of weather and grassland management on emission processes. Emission factors, used to compile regional inventories, are hugely variable and still very uncertain despite decades of research.
Pastures are an important source of ammonia, a major atmospheric pollutant with manifold...
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