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Challenges in quantifying biosphere-atmosphere exchange of nitrogen species
2007
Sutton, M.A. | Nemitz, E. | Erisman, J.W | Beier, C. | Butterbach Bahl, K. | Cellier, Pierre | de Vries, W. | Cotrufo, F. | Skiba, U | Di Marco, C. | Jones, S. | Laville, Patricia | Soussana, Jean-François | Loubet, Benjamin | Twigg, M. | Famulari, D. | Whitehead, J. | Gallagher, M.W. | Neftel, A. | Flechard, C.R. | Herrmann, B. | Calanca, P.L. | Schjoerring, J.K. | Daemmgen, U. | Horvath, L. | Tang, Y.P. | Emmett, B.A. | Tietema, A. | Penuelas, J. | Kesik, M. | Brueggemann, N. | Pilegaard, K. | Vesala, T. | Campbell, C.L. | Olesen, J.E. | Dragosits, U. | Theobald, M.R. | Levy, P. | Mobbs, D.C. | Milne, R. | Viovy, N. | Vuichard, N. | Smith, J.U. | Smith, P. | Bergamaschi, P. | Fowler, D. | Reis, S. | Centre for Ecology and Hydrology | Clean Fossil Fuels ; Energy Research Centre of the Netherlands (ECN) | Risø National Laboratory ; Danish Ministry of Science, Technology and Innovation | Institut für Meteorologie und Klimaforschung - Atmosphärische Umweltforschung (IMK-IFU) ; Karlsruher Institut für Technologie (KIT) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Wageningen University and Research [Wageningen] (WUR) | Seconda Università degli Studi di Napoli = Second University of Naples | Unité de recherche Agronomie de Clermont (URAC) ; Institut National de la Recherche Agronomique (INRA) | University of Manchester [Manchester] | Agroscope | Royal Veterinary and Agricultural University = Kongelige Veterinær- og Landbohøjskole (KVL ) | Institut für Agrarekologie | Hungarian Meteorological Service (OMSZ) | Centre for Ecology and Hydrology [Bangor] (CEH) ; Natural Environment Research Council (NERC) | University of Amsterdam [Amsterdam] (UvA) | Center for Ecolological Research and Forestry Applications | Helsingin yliopisto = Helsingfors universitet = University of Helsinki | Danish Institute of Agricultural Sciences | Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Modélisation des Surfaces et Interfaces Continentales (MOSAIC) ; Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE) ; Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | University of Aberdeen | JRC Institute for Environment and Sustainability (IES) ; European Commission - Joint Research Centre [Ispra] (JRC)
Recent research in nitrogen exchange with the atmosphere has separated research communities according to N form. The integrated perspective needed to quantify the net effect of N on greenhouse-gas balance is being addressed by the NitroEurope Integrated Project (NEU). Recent advances have depended on improved methodologies, while ongoing challenges include gas-aerosol interactions, organic nitrogen and N2 fluxes. The NEU strategy applies a 3-tier Flux Network together with a Manipulation Network of global-change experiments, linked by common protocols to facilitate model application. Substantial progress has been made in modelling N fluxes, especially for N2O, NO and bi-directional NH3 exchange. Landscape analysis represents an emerging challenge to address the spatial interactions between farms, fields, ecosystems, catchments and air dispersion/deposition. European up-scaling of N fluxes is highly uncertain and a key priority is for better data on agricultural practices. Finally, attention is needed to develop N flux verification procedures to assess compliance with international protocols
Show more [+] Less [-]Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France
2008
Banas, Damien | Masson, Gérard | Leglize, L. | Usseglio-Polatera, Philippe | Boyd, C.E. | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Université Paris-Sud - Paris 11 (UP11) | Centre National de la Recherche Scientifique (CNRS) | AgroParisTech | Université Paul Verlaine - Metz (UPVM) | Auburn University (AU)
International audience | Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2–620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L. Effluent phosphorus loads were higher than those reported for more intensive aquaculture ponds, but the pollutant source was catchments rather than feeds and fertilizers.
Show more [+] Less [-]Vertical flow constructed wetlands subject to load variations : an improved design methodology connected to outlet quality objectives. | Filtres plantés de roseaux soumis à variation de charges : quel dimensionnement pour quel objectif de qualité ?
2014
Boutin, Catherine | Prost Boucle, S.
This study set out to assess how vertical flow constructed wetlands (vfCW) adapt to different types of tourism-driven variations in influent load, i.e. (i) campsites, closed for six months of the year and featuring a two-month-only window of high-season activity, and (ii) tourist-interest villages either hosting tourists over at least the six months of summer while the permanent population is resident or summer festivals that create intense pollution loads in a short burst of just a few days. The study surveyed 4 campsites and 4 tourist-interest villages that were monitored for several years, generating over 70 performance balances for vfCW that were intentionally scaled down in relation to the conventional French design for experimental trials. The influent wastewater effectively qualifies as domestic sewage, although relatively concentrated, with the campsites presenting particularly high nitrogen concentrations (122 gTKN.L-1). The applied daily loads were also particularly high, with some combinations of load parameters (hydraulic load, organic matter, TKN) leading to 400% overloading. Even under these drastic conditions, quality of effluent remained excellent on the characteristic organic matter parameters, with removal performances always over 85%. However, nitrification performances were poor to good. Analysis of the dataset points to two major design thresholds: For campsites, in order to keep a 73% nitrification rate even at the height of the summer season, the load applied to the 1st stage filter in operation has to be capped at less than 600 gCOD.m-².d-1. For tourist-interest villages, in order to keep an 85% nitrification rate in the summer season, the load applied to the 2nd stage filter in operation has to be capped at less than 22 gTKN.m-².d-1. Here, vfCW were demonstrated to robustly handle a massive increase in loads applied, providing the wetland construction and operation stringently follow best design standards and practices.
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