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1. A sub km resolution global database of surface reflectance and emissivity based on 10-years of MODIS data

Author

Karine Caillault, François-Marie Bréon, Xavier Briottet, Louis Gonzalez, Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), ONERA - The French Aerospace Lab [Toulouse], ONERA, 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), and 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)

Subjects
Earth observation, 010504 meteorology & atmospheric sciences, Meteorology, Cloud cover, 0211 other engineering and technologies, 02 engineering and technology, Land cover, Residual, computer.software_genre, 01 natural sciences, Emissivity, Computers in Earth Sciences, Engineering (miscellaneous), Image resolution, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Data processing, Database, Atmospheric correction, TERRA, 15. Life on land, Atomic and Molecular Physics, and Optics, Computer Science Applications, REFLECTANCE, MODIS, 13. Climate action, AQUA, GLOBAL DATABASE, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Environmental science, computer, CLIMATOLOGY
Abstract

International audience; The MODIS instruments have been flying onboard the Terra and Aqua platforms and have acquired Earth observation data since early 2000 and mid 2002, respectively. After atmospheric correction, the collected data allows the monitoring of the land cover dynamics. Here, we describe a data processing scheme to generate Earth reflectance and emissivity time series at a sub-kilometer spatial resolution and with a period of 8 days. The data processing scheme removes residual cloud and aerosol contamination in the MODIS products, applies directional correction, and fills the gaps resulting from persistent cloud cover. The resulting database, referred to FondsDeSol, offers a significant improvement with respect to the first version proposed in (Gonzalez et al., 2010), and covers a period of ten years against only one year for the first version. The first motivation of the database is to improve the estimation of at sensor radiances for the design of future sensor in the optical domain. Nevertheless, such database opens the way to new research topics like land surface dynamics, land cover changes, and inter-annual variations due to climate perturbations.; Les instruments MODIS volent sur les plateformes TERRA et AQUA et acquièrent des données d'observation de la Terre depuis début 2000 et mi-2002 respectivement. Après correction atmosphérique, les données collectées permettent le suivi de la dynamique de l'occupation des sols. Dans ce papier, nous décrivons le traitement des données permettant la génération de séries temporelles de réflectances et d'émissivités de la surface à une résolution spatiale sub-kilométrique et avec une période de 8 jours. Au cours du traitement des données, les nuages et la contamination par les aérosols résiduels sont éliminés des produits MODIS, une correction directionnelle est appliquée et les trous résultants d'une couverture nuageuse persistante sont comblés. La base de données FondsDeSol ainsi obtenue offre une amélioration significative au regard de la première version proposée dans (Gonzalez et al. 2010), et couvre une période de 10 ans au lieu de 1 ans pour la première version. La première motivation de cette nouvelle base est d'améliorer l'estimation des luminances pour aider au développement de nouveaux capteurs optiques. Néanmoins, une telle base de données ouvre la voie à de nouveaux sujets de recherche en dynamique de la surface, pour l'étude du changement dans l'occupation des sols ou des variations inter-annuelles dues aux perturbations climatiques.

Published
2016
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2. Metal measurement in aquatic environments by passive sampling methods: Lessons learning from an in situ intercomparison exercise

Author

Aymeric Dabrin, J. P. Ghestem, Jean-Louis Gonzalez, Ian Allan, Marina Coquery, E. Peinerud, Cecile Miege, Marco Schintu, Emmanuelle Uher, Jan Balaam, Natalia Montero, Milieux aquatiques, écologie et pollutions (UR MALY), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Hydrosystèmes et Bioprocédés (UR HBAN), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), School of Earth, Atmospheric and Environmental Sciences [Manchester] (SEAES), University of Manchester [Manchester], Norwegian Institute for Water Research (NIVA), Universita degli Studi di Cagliari [Cagliari], AZTI - Tecnalia, Centre for Environment, Fisheries and Aquaculture Science [Lowestoft] (CEFAS), ALS Scandinavia, and Hydrosystèmes et bioprocédés (UR HBAN)

Subjects
In situ, Health, Toxicology and Mutagenesis, Blank, 010501 environmental sciences, Toxicology, CONTINENTAL WATERS, 01 natural sciences, Metal, Environmental monitoring, 0105 earth and related environmental sciences, Pollutant, Continental waters, Aquatic ecosystem, 010401 analytical chemistry, Uncertainty, Sampling (statistics), General Medicine, DGT, Pollution, 0104 chemical sciences, Fresh water, Metals, 13. Climate action, Environmental chemistry, visual_art, [SDE]Environmental Sciences, Coastal waters, visual_art.visual_art_medium, Environmental science, BLANK, COASTAL WATERS, Water Pollutants, Chemical, Environmental Monitoring, Passive sampling
Abstract

International audience; Passive sampling devices (PS) are widely used for pollutant monitoring in water, but estimation of measurement uncertainties by PS has seldom been undertaken. The aim of this work was to identify key parameters governing PS measurements of metals and their dispersion. We report the results of an in situ intercomparison exercise on diffusive gradient in thin films (DGT) in surface waters. Interlaboratory uncertainties of time-weighted average (TWA) concentrations were satisfactory (from 28% to 112%) given the number of participating laboratories (10) and ultra-trace metal concentrations involved. Data dispersion of TWA concentrations was mainly explained by uncertainties generated during DGT handling and analytical procedure steps. We highlight that DGT handling is critical for metals such as Cd, Cr and Zn, implying that DGT assembly/dismantling should be performed in very clean conditions. Using a unique dataset, we demonstrated that DGT markedly lowered the LOQ in comparison to spot sampling and stressed the need for accurate data calculation.

Published
2016
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3. Impact of Galvanic Anode Dissolution on Metal Trace Element Concentrations in Marine Waters

Author

Christelle Caplat, Anne-Marie Grolleau, Samuel Pineau, Philippe Refait, Jonathan Deborde, Olivier Basuyaux, Paco Bustamante, Jean-Louis Gonzalez, Marie-Laure Mahaut, Christophe Brach-Papa, Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences de l'Ingénieur pour l'Environnement - UMR 7356 (LaSIE), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Sorbonne Université (SU)-Université des Antilles (UA)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Recherche pour le Développement (IRD), Synergie MEr et Littoral (SMEL), DCNS Group (DCNS), DCNS group, Laboratoire de Chimie Biologique (LCB), Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire Biogéochimie des Contaminants Métalliques (LBCM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre atlantique, Nantes, Perception, decision and action of real and virtual humans in virtual environments and impact on real environments (BUNRAKU), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Cachan (ENS Cachan)-Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria), Chercheur indépendant, Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Institut national des sciences et techniques de la mer (INTECHMER), Conservatoire National des Arts et Métiers [CNAM] (CNAM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM), Biogéochimie et Ecotoxicologie (BE), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)

Subjects
Environmental Engineering, Materials science, 010504 meteorology & atmospheric sciences, Galvanic anode, chemistry.chemical_element, Zinc, 010501 environmental sciences, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 01 natural sciences, Corrosion, Cathodic protection, Metal transfer, contamination, Galvanic cell, Environmental Chemistry, Seawater, 14. Life underwater, Dissolution, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Water Science and Technology, seawater, Ecological Modeling, Metallurgy, zinc, Pollution, 6. Clean water, Anode, chemistry, 13. Climate action, aluminum, [SDE]Environmental Sciences, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, Aluminum
Abstract

International audience; Submerged harbor steel structures often employ cathodic protection using galvanic anodes to guard against corrosion. A laboratory experiment, with three different cathodic protection config-urations by galvanic aluminum-based anodes, was performed to evaluate the potential metal trans-fer from the anodic alloy dissolution into the surrounding marine water. The anode dissolution rate is proportional to the imposed current demands and induced a significant Al, In, and Zn trans-fer in the dissolved and particulate fractions of the corrosion product layers covering the anode surface. These layers were poorly adherent, even under low hydrodynamic conditions. Conse-quently, at the anode vicinity, the suspended particle matter and dissolved fraction of surrounding marine waters showed strong enrichments in Al and Zn, respectively, the values of which could potentially affect the adjacent biota. After the anode activation period, however, the metal inputs from galvanic anode dissolution are rapidly diluted by seawater renewal. At regional scale, these metal fluxes should be negligible compared to river and wastewater fluxes. These results also showed that it is difficult to assess the impact of the anode dissolution on the concentrations of metals in the natural environment, especially for metals included in trace amounts in the anode alloy (i.e., Cu, Fe, In, Mn, and Si) in the aquatic compartment.

Published
2015
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4. Evidencing the Impact of Coastal Contaminated Sediments on Mussels Through Pb Stable Isotopes Composition

Author

Lionel Dutruch, Jean François Chiffoleau, Cédric Garnier, Véronique Lenoble, Jörg Schäfer, Duc Huy Dang, Gaël Durrieu, Gérard Blanc, Jean Louis Gonzalez, Christophe Brach-Papa, Jean Ulrich Mullot, Stéphane Mounier, PROcessus de Transfert et d'Echanges dans l'Environnement - EA 3819 ( PROTEE ), Université de Toulon ( UTLN ), Institut Français de Recherche pour l'Exploitation de la Mer ( IFREMER ), LASEM, Processus de Transfert et d'Echanges dans l'Environnement - EA 3819 (PROTEE), Université de Toulon (UTLN), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)

Subjects
Pollution, Geologic Sediments, media_common.quotation_subject, Aquaculture, Environment, Isotopic signature, Water column, Mediterranean sea, Isotopes, Rivers, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Mediterranean Sea, Animals, Environmental Chemistry, Seawater, 14. Life underwater, Ecosystem, media_common, Stable isotope ratio, Sediment, General Chemistry, Bivalvia, Coal, Oceanography, Lead, 13. Climate action, [ CHIM.ANAL ] Chemical Sciences/Analytical chemistry, France, Bay, Geology, Environmental Monitoring
Abstract

International audience; Heavily-contaminated sediments are a serious concern for ecosystem quality, especially in coastal areas, where vulnerability is high due to intense anthropogenic pressure. Surface sediments (54 stations), 50-cm interface cores (5 specific stations), river particles, coal and bulk Pb plate from past French Navy activities, seawater and mussels were collected in Toulon Bay (NW Mediterranean Sea). Lead content and Pb stable isotope composition have evidenced the direct impact of sediment pollution stock on both the water column quality and the living organisms, through the specific Pb isotopic signature in these considered compartments. The history of pollution events including past and present contaminant dispersion in Toulon Bay were also demonstrated by historical records of Pb content and Pb isotope ratios in sediment profiles. The sediment resuspension events, as simulated by batch experiments, could be a major factor contributing to the high Pb mobility in the considered ecosystem. A survey of Pb concentrations in surface seawater at 40 stations has revealed poor seawater quality, affecting both the dissolved fraction and suspended particles and points to marina/harbours as additional diffuse sources of dissolved Pb.\backslashnHeavily-contaminated sediments are a serious concern for ecosystem quality, especially in coastal areas, where vulnerability is high due to intense anthropogenic pressure. Surface sediments (54 stations), 50-cm interface cores (5 specific stations), river particles, coal and bulk Pb plate from past French Navy activities, seawater and mussels were collected in Toulon Bay (NW Mediterranean Sea). Lead content and Pb stable isotope composition have evidenced the direct impact of sediment pollution stock on both the water column quality and the living organisms, through the specific Pb isotopic signature in these considered compartments. The history of pollution events including past and present contaminant dispersion in Toulon Bay were also demonstrated by historical records of Pb content and Pb isotope ratios in sediment profiles. The sediment resuspension events, as simulated by batch experiments, could be a major factor contributing to the high Pb mobility in the considered ecosystem. A survey of Pb concentrations in surface seawater at 40 stations has revealed poor seawater quality, affecting both the dissolved fraction and suspended particles and points to marina/harbours as additional diffuse sources of dissolved Pb.

Published
2015
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5. Impact of a river flash flood on microbial carbon and nitrogen production in a Mediterranean Lagoon (Thau Lagoon, France)

Author

Marc Bouvy, Behzad Mostajir, Sébastien Mas, Aurore Trottet, Marie-George Tournoud, Francesca Vidussi, Emma Rochelle-Newall, Christian Salles, Christine Roques, Eric Fouilland, E. Hatey, E. Le Floc'h, Chrystelle Bancon-Montigny, David Pecqueur, J. Nouguier, Claire Rodier, Jean-Louis Gonzalez, Ecologie des systèmes marins côtiers (Ecosym), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS), Hydrosciences Montpellier (HSM), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre d'Ecologie marine expérimentale (MEDIMEER), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Biogéochimie et écologie des milieux continentaux (Bioemco), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), MARine Biodiversity Exploitation and Conservation (UMR MARBEC), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Ecosystèmes lagunaires : organisation biologique et fonctionnement (ECOLAG), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Universidad Politécnica de Valencia, Observatoire de REcherche Méditerranéen de l'Environnement (OSU OREME), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut des Sciences de la MER de Rimouski (ISMER), Université du Québec à Rimouski (UQAR), UR 103 Camélia, Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Laboratoire de génie chimique [ancien site de Basso-Cambo] (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de Synthèse et Fonctionnalisation de Céramiques (UMR 3080), Saint Gobain, Laboratoire d'océanographie de Villefranche (LOV), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS), and Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, chemistry.chemical_element, metal contaminants, Aquatic Science, Oceanography, 01 natural sciences, phytoplankton and bacteria production, Dissolved organic carbon, Phytoplankton, Trace metal, 14. Life underwater, Turbidity, Mediterranean coastal waters, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Hydrology, Brackish water, DIN uptake rates, 010604 marine biology & hydrobiology, Phosphorus, Sedimentation, Nitrogen, 6. Clean water, chemistry, Environmental chemistry, [SDE]Environmental Sciences, Environmental science, river discharge
Abstract

Over half of the total nitrogen, phosphorus, silicate and dissolved organic carbon (DOC) loading was discharged from the Wile River into the Thau Lagoon waters within the first five days of what was considered to be the autumn flash flood period. Such loads represented about 8% and 3% of the yearly averaged total nitrogen and phosphorus load in Thau Lagoon, respectively. Although this event affected >20% of the total lagoon volume, river trace metal loads contributed apparently only weakly to the increase in labile trace metal concentrations in the lagoon surface waters. Differences between theoretical dilution values and observed values were also noticed for phosphate, silicate and dissolved organic carbon (DOC) concentrations. DOC losses (10-50%) mainly through flocculation, together with the substantial increases in some metallic contaminants such as Zn (from 6 to >30 mu g L-1) observed during the flash flood in saline lagoon waters, may have limited the carbon production of bacterial communities. The potential osmotic shock and the increase in turbidity may mainly explain the low phytoplankton C turnover rates (average of 0.02 h(-1)) measured in brackish waters (

Published
2012
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6. On a statistical Sofware package for non-expert users

Author

Dimitris Karlis, Gilbert Saporta, Antonis Spinakis, Panagiota Anastasiou, Luan Jaupi, Pierre-Louis Gonzalez, Athens University of Economics and Business (AUEB), CEDRIC. Méthodes statistiques de data-mining et apprentissage (CEDRIC - MSDMA), Centre d'études et de recherche en informatique et communications (CEDRIC), Ecole Nationale Supérieure d'Informatique pour l'Industrie et l'Entreprise (ENSIIE)-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Ecole Nationale Supérieure d'Informatique pour l'Industrie et l'Entreprise (ENSIIE)-Conservatoire National des Arts et Métiers [CNAM] (CNAM), Quantos, and Eurostat

Subjects
[STAT]Statistics [stat], attributes, statistical practice, semi-expert system, user requirements
Abstract

International audience; In recent days, statistical methods are applied in a vast extent of different disciplines by a lot of people that, very often, have a rather little knowledge of statistics. This fact can lead to misuse of statistical methods, mainly due to the fact that the users are not able to evaluate the appropriateness and the applicability of the selected methodology, although these methods are rather simple. In addition, these users can be terrified by a statistical output with which they are not familiar. The statistical community has recognized this fact and now statistical packages try to offer some guidance to their users. This paper presents the design of a statistical package, oriented to users with medium or little knowledge of statistics. This package enhances some kind of ‘expertise’ in order to prevent the users from statistical maltreatment. We focus on the statistical part of such software and mainly on the idea of providing statistical guidance in several steps of the analysis to the user in an elegant way. These steps include selection of the appropriate method, application of the method in an optimum way and construction of outputs that beyond plain numbers offer an explanation of the results in simple language. The results of a survey about the user requirements of such a software are presented.

Published
2001

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