Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic
Volume 9, issue 4
Biogeosciences, 9, 1537–1552, 2012
https://doi.org/10.5194/bg-9-1537-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: Nitrogen and global change

Biogeosciences, 9, 1537–1552, 2012
https://doi.org/10.5194/bg-9-1537-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 26 Apr 2012

Research article | 26 Apr 2012

Investigating the stomatal, cuticular and soil ammonia fluxes over a growing tritical crop under high acidic loads

B. Loubet1, C. Decuq1, E. Personne2, R. S. Massad1, C. Flechard3, O. Fanucci1, N. Mascher1, J.-C. Gueudet1, S. Masson1, B. Durand1, S. Genermont1, Y. Fauvel3, and P. Cellier1 B. Loubet et al.
  • 1INRA, UMR 1091-INRA-AgroParisTech, Environnement et Grandes Cultures, 78850 Thiverval-Grignon, France
  • 2AgroParisTech, UMR 1091-INRA-AgroParisTech, Environnement et Grandes Cultures, 78850 Thiverval-Grignon, France
  • 3INRA, AgroCampus Ouest, UMR 1069 SAS, 65, rue de St-Brieuc, 35042 Rennes, France

Abstract. Ammonia concentration and fluxes were measured above a growing triticale field for two months during May and June 2010 at the NitroEurope crop site in Grignon (Fr-Gri) near Paris, France. The measurement campaign started 15 days following a 40 kg N ha−1 application of an ammonium nitrate solution. A new mini-wedd (Wet Effluent Denuder) flow injection analyser with three channels (ROSAA, RObust and Sensitive Ammonia Analyser) was used to measure NH3 fluxes using the aerodynamic gradient method. The measured ammonia concentrations varied from 0.01 to 39 μg NH3 m−3 and were largely influenced by advection from the nearby farm. The ammonia fluxes ranged from –560 to 220 ng NH3 m−2 s−1 and averaged –29 ng NH3 m−2 s−1. During some periods the large deposition fluxes could only be explained by a very small surface resistance, which may be partly due to the high concentrations of certain acid gases (HNO3 and SO2) observed in this suburban area. Ammonia emissions were also observed. The canopy compensation point Cc was around 1.5 μg NH3 m−3 on average. The canopy emission potential Γc (Cc normalised for the temperature response of the Henry equilibrium) decreased over the course of the measurement campaign from Γc = 2200 to Γc = 450, the latter value being close to the median stomatal emission potential (Γs) and lower than the median ground emission potential (Γg) for managed ecosystems reported in the literature. The temporal dynamics of the measured NH3 flux compared well with the Surfatm-NH3 model using fitted parameters. The subjectivity of the model fitting is discussed based on a sensitivity analysis.

Publications Copernicus
Download
Citation