Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 6 3 2009 10.5194/bg-6-309-2009 http://www.biogeosciences.net/6/309/2009/ http://www.biogeosciences.net/6/309/2009/bg-6-309-2009.html http://www.biogeosciences.net/6/309/2009/bg-6-309-2009.pdf 309 331 2009-03-05 Dynamics of ammonia exchange with cut grassland: strategy and implementation of the GRAMINAE Integrated Experiment M. A. Sutton ms@ceh.ac.uk E. Nemitz M. R. Theobald C. Milford J. R. Dorsey M. W. Gallagher A. Hensen P. A. C. Jongejan J. W. Erisman M. Mattsson J. K. Schjoerring P. Cellier B. Loubet R. Roche A. Neftel B. Hermann S. K. Jones B. E. Lehman L. Horvath T. Weidinger K. Rajkai J. Burkhardt F. J. Löpmeier U. Daemmgen Centre for Ecology and Hydrology (CEH), Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH26 0QB, UK University of Manchester (UoM), Oxford Road, Manchester, M13 9PL, UK Energy research Centre of the Netherlands (ECN), Postbus 1, 1755 ZG Petten, The Netherlands Plant and Soil Science Laboratory, University of Copenhagen (UoC), Faculty of Life Sciences, Thorvaldsensvej 40, 871 Frederiksberg C, Copenhagen, Denmark Institut National de la Recherche Agronomique (INRA), UMR Environnement et Grandes Cultures, Thiverval-Grignon, 78850, France Agroscope Reckenholz-Tänikon Research Station (formerly: FAL-CH; now: ART), Zürich-Reckenholz, 8046 Zürich, Switzerland Hungarian Meteorological Service (HMS), P.O. Box 39 1675 Budapest, Hungary (in association with the Forest Research Institute (FRI) of Hungary), Hungay Eötvös Loránd University (ELU), Dept. Meteorology, 1117 Budapest, Hungary Research Institute of Soil Science and Agrochemistry of Hungary (RISSAC), Herman Ottó út 15, 1022 Budapest, Hungary University of Bonn, Institute for Crop Science and Resource Conservation, INRES-PE, Karlrobert-Kreiten-Str. 13, 53115 Bonn, Germany Agrometeorological Research Station of Deutscher Wetterdienst (DVD), Bundesallee 50; 38116 Braunschweig, Germany Institut fur Agrarokologie, Bundesforschungsanstalt fur Landwirtschaft (FAL), (now: the von Thunen Institute), Bundesallee 50, 38116 Braunschweig, Germany now at: Institute of Earth Sciences "Jaume Almera", CSIC, Lluis Solé i Sabarís, 08028, Barcelona, Spain now at: Section for Economy & Technology, Halmstad University, 30118 Sweden formerly at: University of Bern, Hochschulstr. 4, 3012 Bern, Switzerland deceased A major international experiment on ammonia (NH₃) biosphere-atmosphere exchange was conducted over intensively managed grassland at Braunschweig, Germany. The experimental strategy was developed to allow an integrated analysis of different features of NH₃ exchange including: a) quantification of nearby emissions and advection effects, b) estimation of net NH₃ fluxes with the canopy by a range of micrometeorological measurements, c) analysis of the sources and sinks of NH₃ within the plant canopy, including soils and bioassay measurements, d) comparison of the effects of grassland management options on NH₃ fluxes and e) assessment of the interactions of NH₃ fluxes with aerosol exchange processes. Additional technical objectives included the inter-comparison of different estimates of sensible and latent heat fluxes, as well as continuous-gradient and Relaxed Eddy Accumulation (REA) systems for NH₃ fluxes. <br><br> The prior analysis established the spatial and temporal design of the experiment, allowing significant synergy between these objectives. The measurements were made at 7 measurement locations, thereby quantifying horizontal and vertical profiles, and covered three phases: a) tall grass canopy prior to cutting (7 days), b) short grass after cutting (7 days) and c) re-growing sward following fertilization with ammonium nitrate (10 days). The sequential management treatments allowed comparison of sources-sinks, advection and aerosol interactions under a wide range of NH₃ fluxes. <br><br> This paper describes the experimental strategy and reports the grassland management history, soils, environmental conditions and air chemistry during the experiment, finally summarizing how the results are coordinated in the accompanying series of papers. Achermann, B. and Bobbink, R.: Empirical critical loads for Nitrogen (Report of UNECE Expert Workshop, Berne 11–13 November 2002). SAEFL, Berne, Switzerland, 2003. Adams, P. J., Seinfeld, J. 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