Devenir des micropolluants dans les traitements tertiaires et traitements des boues
(pp. 22, 29/08/2026)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Use of integrative samplers for the determination of the efficiency of wastewater advanced treatments: case of pharmaceuticals compounds
Introduction. The general objective of the ECHIBIOTEB research program (“Innovating tools for sampling, chemical and biological analyses for the diagnosis of wastewater advanced tertiary treatments and sludge treatments”, 2011-2014, financed by the French National Research Agency) is introduced in a previous presentation. Briefly it consists in developing new tools for the determination of the efficiency of advanced treatments, especially for the sampling. This presentation will describe the potential of Polar Organic Chemical Integrative Sampler (POCIS) for the monitoring of pharmaceuticals in water, compared to grab sampling. Analytical methodology. Until today, two campaigns were performed in order to follow the efficiency of ozone (O3) treatment, alone and coupled with Granular Activated Carbon (GAC) by exposing 20 POCIS before and after the wastewater treatment during 28 days. Each triplicate, associated to a field blank, is dedicated to a kind of analysis (pharmaceuticals, alkylphenols, and biological analysis, for example). In parallel, grab samplings were achieved after 0, 14 and 28 days of POCIS exposition in order to compare these two approaches. 104 molecules belonging to several therapeutic classes such as antibiotics, -blockers, antineoplastics, antivirals, phosphodiesterase type 5 inhibitor (PDE 5), analgesics, broncholidators, non-steroidal anti-inflammatory and psychiatric drugs, lipid regulators and stimulants, were analysed. Therefore, in order to determine the in-situ rate constants of exposed POCIS, 3 Reference Performance Compounds (PRC) were previously added in the adsorbant phase: salbutamol-d3, caffeine-13C and desisopropylatrazin-d5 (DIA d5) and laboratory calibration on pharmaceuticals were performed. Solid Phase Extractions (SPE) were carried out on the different samples depending on compound classes and, then, analyses were performed by liquid phase chromatography coupled with tandem mass spectrometry (LC-MS/MS). Results. Among targeted compounds, 39 molecules were not detected in any samples of wastewater, in the dissolved phase and 32 molecules in any POCIS samplers. As illustrated in Figure 1a, concentrations upstream from the treatments are higher than those downstream; whatever is the nature of wastewater process. Betablockers, macrolides, psychiatric drugs, fluoroquinolones and quinolones are the most abundant compounds upstream these processes and downstream, only two classes (Betablockers and stimulants) remain present as relatively high concentrations. Therefore, it seems that GAC and GAC+O3 treatments involve a drastic reduction of micropollutant concentrations in wastewaters. Regarding concentrations determined in the adsorbant phase of passive samplers (Figure 1b), the tendency between upstream and downstream coincides well with the one of wastewater samples, in terms of pharmaceutical abundances and between samples too. Figure 2 shows that the number of detected targeted compounds depends on the place of sampling (up or downstream) and on the way of sampling (POCIS vs. grab sampling). For the process using granular activated carbon, based on the measurements of 103 molecules, 13 extra compounds are detected in the adsorbant phase of POCIS compared to the dissolved phase, upstream and downstream the process. Until today, regarding the analysis of 93 molecules for ozone+GAC process, the trend is also observed with the detection of 23 and 17 extra compounds, upstream and downstream respectively. These results show the real interest of this sampling mode by the improvement of methodology sensitivity. Laboratory calibration of passive samplers allow to determine rate constants for more than 25 of target compounds and so, to compare directly the results between integrative and grab sampling in terms of concentrations. This methodology of sampling reveals its interest for the quantification of targeted compounds and has been also applied to the analysis of non-targeted compounds in order to complete the knowledge on the efficiency of such process. The presence of pharmaceuticals and non-targeted compounds could explain the potential toxicity of these samples (wastewater and POCIS extracts). Acknowledgements. The authors wish to thank the program ECOTECH-ECHIBIOTEB, the Aquitaine Region and the European Union (CPER A2E project) for financial support. Europe is moving in Aquitaine with the European Regional Development Fund.
(pp. 36, 29/08/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR MALY, IRSTEA
Etude intégrée de l’effet des apports amont et locaux sur le fonctionnement de la Garonne estuarienne (ETIAGE) : Addendum année 2 Avril 2011 - Mars 2012
Le programme ETIAGE a été mis en place avec pour objectif de répondre aux questions suivantes : que représentent les apports des effluents de la Communauté Urbaine de Bordeaux (CUB) par rapport à ceux venant de l’amont en termes de charge organique et de micro-polluants ? Quels rôles sur le devenir des effluents jouent la présence du bouchon vaseux et la stagnation résiduelle des eaux (déplacement net entre mouvement de flot et de jusant) au niveau de l’estuaire fluvial amont en période d’étiage estival ? Réciproquement, à quels moments et jusqu’où s’étend l’impact de ces effluents sur la qualité des eaux de la Garonne estuarienne ? Quelles incidences des effluents sur le comportement des populations biologiques en place ou migratoires dans la Garonne estuarienne ? Quelle tendance évolutive va connaître l’oxygénation des eaux ? Quel sera l’impact sur le comportement des micro-polluants et des populations biologiques ? Quelles recommandations de gestion pourraient être préconisées à partir de la synthèse des pressions exercées sur les eaux de la Garonne estuarienne ? Le programme est divisé en 5 axes, dont les bilans de travail sont présentés axe par axe.
(pp. 172, 29/08/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR EPBX, IRSTEA
A note about the critical bandwidth for a kernel density estimator with the uniform kernel
Among available bandwidths for kernel density estimators, the critical bandwidth is a data-driven one, which satisfies a constraint on the number of modes of the estimated density. When using a random bandwidth, it is of particular interest to show that it goes toward 0 in probability when the sample size goes to infinity. Such a property is important to prove satisfying asymptotic results about the corresponding kernel density estimator. It is shown here that this property is not true for the uniform kernel.
(17/12/2012)
IMB, UB, Bordeaux INP, CNRS, CQFD, IMB, UB, Bordeaux INP, CNRS, Inria, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LMBA, UBS, UBO EPE, CNRS
High-resolution architecture of a polygonal fault interval inferred from geomodel applied to 3D seismic data from the Gjallar Ridge, Vøring Basin, Offshore Norway
3D seismic data located in the Gjallar Ridge (Vøring Basin, offshore Norway) reveals a closely-spaced polygonal fault system affecting more than 800 m of homogeneous mud-dominated Quaternary and Tertiary sequences. As some faults reach the modern seafloor, they represent an active polygonal fault system at present day. Even if the processes remain unclear and are still under debate, it is generally agreed that the initiation of polygonal faults is the result of shallow burial dewatering of fine-grained unconsolidated sediments by volumetric compaction. 3D seismic data are commonly interpreted by propagating horizons automatically and by picking faults manually. However, in the case of polygonal fault intervals, this approach is time consuming due to the huge number of faults and because automatic propagation can be misleading. In this study, we applied a new technique of 3D seismic interpretation based on a sequential stratigraphy analysis, using the new PaleoScan© software (Eliis Company). It allowed us to build a 3D geological model computing more than 300 horizons within the faulted intervals. We then used the coherency attribute, depicting anomalies in the shape of seismic waveform like faults, in order to constrain a possible link between fault distribution and stratigraphic levels. Our approach allows fault throws to be calculated in milliseconds on any polygonal fault plane. The result shows that fault segments have been reactivated by dip-linkage. Distribution of faults depends on mechanical units, intervals characterized by different petrophysical properties, which are independent from lithological and diagenetic changes. According to these results, we propose a model showing the evolution of polygonal fault intervals in which faulting stages are separated by a quiescence phase during burial. A first tier of polygonal faults is initiated at a specific depth, according to the Cam-clay model. Then, following a period of quiescence during which mud-rich sediments continued to accumulate, new fault segments are initiated above the first mechanical unit and within this undeformed interval. New nucleated faults then connect downward to pre-existing underlying polygonal fault system, thus progressively increasing the thickness of the faulted interval.
(Marine Geology. vol. 332-334, n° 0025-3227, pp. 134-161, 01/12/2012)
UAG, INSU - CNRS, UM, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NOC, Géosciences Montpellier, UAG, INSU - CNRS, UM, CNRS, UiO, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS
Early mid-Holocene SST variability and surface-ocean water balance in the southwest Pacific
[1] We present early mid-Holocene records of Sr/Ca,δ18O and δ18Osw from marine archives collected in Vanuatu: two Porites sp. corals (6.7–6.5 ka BP) and a Tridacna maxima giant clam (6.2–6.0 ka BP). Sr/Ca, δ18O, and δ18Osw were used as proxies for sea surface temperature (SST) and sea surface salinity (SSS). The fossil geochemical records were compared to modern Porites sp. and T. maxima records. Reconstructed mean SSTs from the two fossil Porites sp.and from the modern coral are similar, implying that the Western Pacific Warm Pool (WPWP)' southern edge had reached its modern location by 6.7–6.5 ka BP. The post-glacial SST rise in the Southwest Pacific was thus completed by the early mid-Holocene. The two early mid-Holocene corals and the giant clam recorded saltier conditions than modern related to 1) a decoupling between the precipitation regime and the SPCZ due to a northerly position of this climatic feature and 2) an increase of the moisture transport to the extra-tropics, driven by a strengthened or extended Hadley cell. The longest δ18O coral profile displays an El Niño Southern Oscillation (ENSO) signal reduced by 20–30% compared to the period 1928–1992, in concordance with the reduced ENSO variability observed in the Pacific area during the first half of the Holocene. However, the decoupling between the SPCZ and the precipitation regime may have also contributed to the weak ENSO signal recorded in the early mid-Holocene coral δ18O profile.
(Paleoceanography. vol. 27, n° 0883-8305, 01/12/2012)
PALEOPROXUS, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, LOCEAN, IPSL, ENS-PSL, PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, IP Paris, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS
In situ study of short-term variations of redox species chemistry in intertidal permeable sediments of the Arcachon lagoon
(Hydrobiologia. vol. 699, n° 0018-8158, pp. 69-84, 01/12/2012)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS
Seagrass burial by dredged sediments: Benthic community alteration, secondary production loss, biotic index reaction and recovery possibility
In 2005, dredging activities in Arcachon Bay (France) led in burying 320,000m(2) of Zostera noltii intertidal seagrass. Recovery by macrobenthos and seagrass was monitored. Six months after works, seagrass was absent and macrobenthos drastically different from surrounding vegetated stations. Rapidly and due to sediment dispersal, disposal area was divided into a sandflat with a specific benthic community which maintained its difference until the end of the survey (2010), and a mudflat where associated fauna became similar to those in adjacent seagrass. Macrobenthic community needs 3years to recover while seagrass needs 5years to recover in the station impacted by mud. The secondary production loss due to works was low. In this naturally carbon enriched system, univariate biotic indices did not perform well to detect seagrass destruction and recovery. Multivariate index MISS gave more relevant conclusions and a simplified version was tested with success, at this local scale.
(Marine Pollution Bulletin. vol. 64, n° 0025-326X, pp. 2340-2350, 01/11/2012)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Accounting for Rough Bed Friction Factors of Mud Beds as a Result of Biological Activity in Erosion Experiments
(Journal of Hydraulic Engineering. vol. 138, n° 0733-9429, pp. 979-984, 01/11/2012)
LECOB, OOB, UPMC, CNRS, UPMC, CNRS, BOREA, UNICAEN, NU, MNHN, IRD, SU, CNRS, UA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IFREMER
Antarctic temperature changes during the last millennium: evaluation of simulations and reconstructions
This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: a b s t r a c t Temperature changes in Antarctica over the last millennium are investigated using proxy records, a set of simulations driven by natural and anthropogenic forcings and one simulation with data assimilation. Over Antarctica, a long term cooling trend in annual mean is simulated during the period 1000e1850. The main contributor to this cooling trend is the volcanic forcing, astronomical forcing playing a dominant role at seasonal timescale. Since 1850, all the models produce an Antarctic warming in response to the increase in greenhouse gas concentrations. We present a composite of Antarctic temperature, calculated by averaging seven temperature records derived from isotope measurements in ice cores. This simple approach is supported by the coherency displayed between model results at these data grid points and Antarctic mean temperature. The composite shows a weak multi-centennial cooling trend during the pre-industrial period and a warming after 1850 that is broadly consistent with model results. In both data and simulations, large regional variations are superimposed on this common signal, at decadal to centennial timescales. The model results appear spatially more consistent than ice core records. We conclude that more records are needed to resolve the complex spatial distribution of Antarctic temperature variations during the last millennium.
(Quaternary Science Reviews. vol. 55, n° 0277-3791, pp. 75-90, 01/11/2012)
TECLIM, ELI, UCLouvain, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, GLACCIOS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, BAS, NERC, AWI, LAL, UP11, IN2P3, CNRS, UvA, ACE-CRC, UGent