Thèses sur le sujet « Matière organique dissoute – Échantillonnage »
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Mougin, Jérémy. « Développement d'outils pour le suivi de la matière organique dans le bassin Artois-Picardie ». Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR003.
The origin and fate of organic matter in watercourses are still poorly understood and requirethe implementation of innovative solutions in line with the problems of the environment studied.For that purpose, a mobile laboratory was entirely designed, built and then automated. Itprovides a secure structure for embedding on-line monitoring equipment, including fluorescenceprobes, allowing high frequency monitoring of the selected study site, here the Marque Rivièrein Hem (France).In addition to this high frequency data, this mobile laboratory allows sampling, a necessarystep for a more complete characterisation of dissolved organic matter. An innovative methodologyhas been developed within the framework of this project, through an optimised samplingalgorithm named « OSA ». It is based on the analysis of high frequency data generated by thelaboratory to drive an automatic sampler-filter.The samples collected provided additional insights on the behaviour of dissolved organicmatter at this site and allowed identifying some of its sources. The influence of wastewatertreatment plants located upstream of the study site was particularly pointed out, showing arelevant impact on the variability of organic matter in the river. The operational strategy alsomade it possible to monitor specific and short events, such as soil leaching following heavyrainfall, with specific organic matter inputs
De, Perre Chloé. « Etude des interactions matière organique dissoute : contaminants organiques dans l'environnement aquatique ». Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13933/document.
In relation with a widespread human impact on aquatic resources and ecosystems, many organic chemical contaminants are present at trace levels in aquatic environments. In parallel to these contaminants, dissolved organic matter (DOM), which is composed of complex mixtures of molecules and macromolecules, is also found and could be associated with these contaminants and influence their behavior and distribution. Interactions between DOM and contaminants can be very difficult to understand because they depend on many factors such as the nature of contaminants and DOM, as well as on environmental physico-chemical parameters. The aim of this work was thus to study these interactions. Organic contaminants studied were Polycyclic Aromatic Hydrocarbons (PAHs) and pharmaceuticals. On the other hand, several types of natural and commercial DOM have been used. To study the interactions, several analytical techniques have been developed like solid phase microextraction coupled to gas chromatography and mass spectrometry and fluorescence quenching
Landa-Bezwierchy, Marine. « Lien entre matière organique dissoute et diversité des communautés bactériennes hétérotrophobes marines ». Paris 6, 2013. http://www.theses.fr/2013PA066460.
Knoth, de Zarruk Katrin. « Transferts réactifs et mobilité de la matière organique dissoute dans les sols ». Avignon, 2007. http://www.theses.fr/2007AVIG0605.
DOM is present in all soils, waters and organic wastes and can be important in binding and co-transporting metals and organic polluants, there fore endangering the quality of potable waters. Dom is higly variable over space and time, which complicates its characterization. A new approach to DOM, a bottom-up approach is presented that concentrates on the molecular composition of DOM. By the means of a thorough literature research, the importance of simple individual compounds in environmental processes is demonstrated. Dialysis of DOM from different sources revealed a great variability of DOM samples in respect of molecular composition and size. Eighty, 70, 50 and 40% of the total organic carbon (TOC) was found in the fractions with low molecular weight in vinasse, leaf compost, soil and chicken manure, respectively. More than 40% of the TOC in vinasse and leaf compost belonged to the fraction with a molecular weight <500 Da, revealing the abundance of small weight in vinasse, suggesting a potential co-transport of copper by low molecular weight compounds. In order to enable us to better estimate the true co-transport of copper by low molecular weight compounds, column experiments were conducted to determine sorption and biodegradation dynamics for a set of selected compounds (glucose, glucosamine, glucuronic acid, alanine, citric acid, acetic acid, caffeic acid, dextran). Results showed that functional group content plays a major role in compound mobility. Even seemingly similar molecules that only differ in one functional group are sorbed and biodegraded in very different manners. Afters combining metal-complexing with sorption and biodegradation parameters, acetic acid was found to be the compound with the highest co-transport potential
Martin, Bénédicte. « La matière organique naturelle dissoute des eaux de surface : fractionnement, caractérisation et réactivité ». Poitiers, 1995. http://www.theses.fr/1995POIT2268.
El-Nahhal, Ibrahim. « Impact de la matière organique anthropique issue des stations d'épurations sur la fluorescence de la matière organique en zone côtière ». Thesis, Toulon, 2018. http://www.theses.fr/2018TOUL0005/document.
Anthropogenic activities have done major changes to our global system. The coastal dissolved organic matter has great influenceon the global carbon cycle and hence climate change. The riverine input of dissolved organic matter represents the terrestrialorganic matter. Urbanized rivers is greatly impacted by the anthropogenic dissolved organic matter coming from wastewatertreatment plants . Chromophoric dissolved organic matter is a subgroup of the dissolved organic matter which can absorb light.Fluorescent dissolved organic matter in turn is a subgroup of the chromophoric dissolved organic matter .The fluorescence signalof the anthropogenic dissolved organic matter in the coastal zone is not well characterized and evaluated in the literature.Photochemically induced degradations and changes at the molecular level is considered to be a great process which could influencethe dissolved organic matter . In the present study, Laboratory mixing experiments several sunlight irradiation experiments wereconducted with several modes of filtration of three endmember mixing components ( River water, Sea water , wastewater treatmentplant effluent discharge) with the objective of finding a specific signal of fluorescence which could be a tracer of the anthropogenicdissolved organic matter through using the fluorescence spectroscopy excitation emission matrices (EEMs) coupled with thechemometric statistical technique of Parallel Factor analysis CP/PARAFAC. Moreover, multilinear regression model between thecontribution of CP/PARAFAC components and two content fraction of River water and Seawater endmember was developed. Inaddition the kinetics of the multilinear regression parameters were investigated. On top of that , geographical investigations of theevolution of fluorescence signal in the Gapeau river till the sea were conducted. Furthermore, Temporal investigation of thefluorescence signal for four water points in the pathway of Gapeau river were done. The multilinear regression model developedwas applied to model the results of the geographical and temporal field experiments. Results have shown that Multilinearregression model for contribution of CP/PARAFAC components is excellent and could be done for the three endmembers. Inaddition the search for specific fluorescence signal or signature for river water, wastewater treatment plants and sea water couldn’tbe done in this work. In human impacted coastal zone, residual fluorescent organic matter come from wastewater treatment plant,and no specific signal from sea water could be detected near the coast
Semaoune, Priscillia. « Dynamique de l'azote à l'interface sol-plante, relation avec la matière organique des sols : apport de la géochimie organique et de la biogéochimie isotopique ». Paris 6, 2012. http://www.theses.fr/2012PA066122.
The purpose of this study is a better understanding of the processes involved in the N transfer in soils and soil-plant interface, and the link between the chemical structure of SOM and DOM and NO3- and NH4+ in the soil solution. We experimentally showed that the transport of NO3- in water did not affect their isotopic composition for N and O. The net uptake of maize grown hydroponically with NH4+ or NO3-, revealed a fractionation associated with absorption probably due to an efflux of enriched inorganic N from roots. 15N enrichment was observed in leaves compared to roots, the measurement of δ15N-NO3- in tissue revealed the role of assimilation in this discrimination. The study of continuum SOM, DOM and inorganic N was performed on the watershed Kerrien in permanent grassland. Samples of soil were realized at different depths and along the slope with contrasting water conditions during high and low water periods. The SOM and the DOM were characterized at the molecular level by 13C NMR and pyrolysis. Isotopic biogeochemistry was used to identify the origin of C and N and to trace the processes. We observed an influence of hydromorphic on the continuum. Evolution of δ13C along the transect reflects the preferential degradation of OM, variations with depth resulting from degradation and fractionation associated with microbial respiration. We distinguished three types of profiles along the slope: high in culture, medium in grassland, low in high waterlogging, which reveal the involvement of different processes
Cotrim, Da Cunha Leticia. « Caractérisation de la matière organique particulaire et dissoute dans un fleuve méditerranéen, le Tech ». Perpignan, 2000. http://www.theses.fr/2000PERP0376.
Characterisation of organic matter in small rivers and streams is important to qualify the impact of human activity and identify the main biogeochemical processes in the drainage basin. Small drainage basin areas enable a better approach to characterise and qualify the riverine organic matter
Massicotte, Philippe. « Modélisation et simulation de la dynamique de la matière organique dissoute en milieu fluvial ». Thèse, Université du Québec à Trois-Rivières, 2012. http://depot-e.uqtr.ca/4459/1/030309442.pdf.
Boualam, Marc. « Origine de la matière organique et devenir de bactéries coliformes dans des eaux faiblement nutritives ». Nancy 1, 2001. http://www.theses.fr/2001NAN12009.
Coliform bacteria are faecal contamination indicators and their detection in treated waters is a frequent cause of health non-compliance. Survival of these organisms is strongly related to the biodegradable dissolved organic matter (DOM) of waters. The aim ofthis research work is to underline the influence of the origin of DOM on the fate of planctonic and fixed coliform bacteria in low nutritive waters (river water sampled after heavy rainfalls and algal bloom water), conveying specific organic matrix, of which a fraction is likely to pass through the treatment barrier. The study of coliforms behaviour in drinking waters, without disruption of their nutritive status (DOC ranged from 1. 5 to 2 mg L-1 with BDOC near to 30%) indicates a rapid culturability loss and the absence of durable colonisation of pilot systems. On the other hand, these bacteria are able to keep their culturability at least 28 days in low nutritive waters having DOC concentrations classically observed in drinking waters. A relationship specific of the water type between biodegradable DOC and coliforms culturability loss, clearly appears. Finally, these bacteria keep their capacity to multiply, even when they loss their culturability, suggesting a viable but non-culturable physiological state. The following of coliforms biofilm development by FTIRIATR spectroscopy in low nutritive waters and in a drinking water confirms the previous observations. The biofilm is stable for 15 days in low nutritive waters, whereas its presence become unsignificant only after one day in the drinking water
Tedetti, Marc. « Impact du rayonnement ultraviolet sur la phototransformation de la matière organique dissoute en milieu marin ». Aix-Marseille 2, 2006. http://theses.univ-amu.fr.lama.univ-amu.fr/2006AIX22058.pdf.
Ferretto, Nicolas. « Etude de la matière organique dissoute fluorescente naturelle et anthropique en Méditerranée côtière nord-occidentale ». Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4024/document.
The Marseille bay is impacted by inputs of freshwater from the Rhône River and effluents. Their impact on composition and seasonal variability of anthropogenic (hydrocarbons and biocides) and natural dissolved organic matter (DOM), present in the Rhône river, the Rhône delta and in the Marseille Bay is still poorly documented. A part of the DOM has fluorescence properties (FDOM) and can be characterised and quantified by spectrofluorimetry. The goal of this thesis was to supply knowledge about composition and dynamic of anthropogenic and natural FDOM in inland waters of the Rhône basin and in the North-western coastal Mediterranean Sea. Standard solutions allowed to define fluorescence properties (λEx, λEm, lifetime), detection limits of hydrocarbons and targeted biocides and to show that spectrofluorimetry allow to characterise and to quantify anthropogenic FDOM in contaminated environment. These contaminants were searched in the environment with chromatography analyses and bring out in the environment during a one year monitoring. However, the spectrofluorimetry not succed to bring out contaminants only in the Fos gulf. Concerning natural FDOM, it allowed to show that terrigenous DOM predominated in continental waters, whereas the DOM produced by the biological activity was more abundant in seawater and that the Rhône River played a major role by increasing both refractory and labile DOM through direct inputs and by enhancing the primary production by nutrient inputs
Souza, Sierra Maria Marta de. « Caractérisation et réactivité de la matière organique fluorescente dissoute dans des milieux côtiers et marins ». Bordeaux 1, 1992. http://www.theses.fr/1992BOR10543.
Blanchet, Marine. « Modifications métaboliques et structurelles des communautés de bactéries marines exposées à différentes qualités de matière organique ». Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066092/document.
Heterotrophic bacterial communities in marine environment are exposed to a heterogeneous mixture of dissolved organic compounds with different bioavailability that may control both their activities and their composition. In the frame of this thesis, we studied the response of different coastal bacterial communities to the single or combined addition of various natural dissolved organic matter (DOM) photo-oxidized or not, presenting different bioavailability characteristics. Firstly, we studied the effects of the addition of highly bioreactive DOM derived from jellyfish on bacterial activities and community structure in a Mediterranean coastal lagoon. We observed that resilience of the bacterial community after the addition of DOM from the jellyfish was higher for metabolic functions than diversity, suggesting that jellyfish blooms can induce durable changes in the bacterial community structure in coastal lagoons. Secondly, we investigated the occurrence of priming effect (increase in microbial degradation of refractory DOM upon the addition of labile DOM) on coastal marine environments. Experiments with single or combined additions of recalcitrant and labile DOM sources were performed with a Mediterranean and a Patagonian fjord bacterial communities. In both cases we observed a greater effect of combined addition on bacterial community composition. However we did not observe an increase in recalcitrant DOM degradation of recalcitrant DOM following the addition of labile compounds, suggesting that priming effect did not occur during our experiments. Finally, we studied the impact of contrasted DOM (i.e. recalcitrant riverine DOM, labile phytoplankton-derived DOM) photodegradation on coastal bacterial communities activity and composition. We observed that photodegradation of phytoplankton-derived DOM led to a lower bacterial growth and changes in bacterial community diversity, in favour of Alphaproteobacteria
Louis, Yoann. « Mise au point d'une systématique de caractérisation des interactions Matière Organique Naturelle Dissoute (MOND) – Contaminants métalliques ». Phd thesis, Université du Sud Toulon Var, 2008. http://tel.archives-ouvertes.fr/tel-00410142.
Huguet, Arnaud. « Mise au point de procédés membranaires pour l'étude de la matière organique dissoute en milieux côtiers ». Bordeaux 1, 2007. http://www.theses.fr/2007BOR13504.
Goffin, Angélique. « Potentiel d’utilisation de la spectrofluorimétrie 3D pour la caractérisation en ligne de la matière organique dissoute : de la station d’épuration au milieu récepteur ». Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1218/document.
The work carried out during this PhD, in close collaboration with the Development and Prospective Development Department (DDP) of the Interdepartmental Syndicate for the Sanitation of the Paris Metropolitan Area (SIAAP), is part of the research program MOCOPEE (Research Modeling, Control and Optimization of Water Treatment Processes) and are interested in the potential applications of 3D spectrofluorimetry to characterize dissolved organic matter (DOM) quantity and quality in wastewater treatment plant (WWTP) and in natural middle. The first part of this manuscript is devoted to the potential applications of 3D fluorescence spectroscopy to characterize wastewater DOM quality and quality. A methodology for the treatment of 3D fluorescence spectra based on the use of a deconvolution algorithm named PARAFAC has been applied to wastewater from the Seine Center WWTP. Specific MOD fluorophores were observed, allowing a finer approach to the fluorescence characteristics of MOD. Resin fractionation and a biodegradability study yielded new information on raw sewage DOM fluorophores. Relationships between DOM fluorescence indicators and soluble Biological Oxygen Demand (BOD5) measurements as well as soluble Chemical Oxygen Demand (COD) measurements have been demonstrated in raw sewage from 6 Parisian WWTP (SIAAP). Prediction models of soluble BOD5 and soluble COD by 3D spectrofluorimetry can be used to anticipate variations of raw sewage quality and quantity, and to optimize biological treatment processes (eg reagent additions). Finally, DOM fluorescence was analyzed along "Seine Center" and "Seine Grésillons" WWTPs. The second part deals with applications potential of 3D fluorescence spectroscopy in natural middles. Thanks to the MeSeine monitoring network (Mesure en Seine), a total of 373 samples were taken during a weekly monitoring from July 2015 to June 2016 in the Seine catchment area and include 12 sampling points from upstream to downstream of Paris and two of its main tributaries (Marne river and Oise river). From this monitoring, a PARAFAC model with 10 components was highlighted. Variations in DOM quality were observed between the different streams studied. The impact of urban pressure on DOM quality was also observed by fluorescence, between the upstream and downstream of the Parisian agglomeration. We have also been able to monitor WWTP effluent impacts on the Seine during a maintenance operation for its treatment processes. Variations in the quality of MOD between low and high water periods were also observed. Thus, 3D spectrofluorimetry help to provide a rapid physicochemical characterization of DOM and its sources in urban aquatic environments. Theses information will help drinking water plants managers to rapidly know DOM quality to anticipate formation of disinfections by-products. Managers of aquatic environments will also be able to anticipate occurrence of surface water pollution episodes. Finally, 3D fluorescence spectroscopy and absorbance spectroscopy were combined to develop a dissolved organic carbon concentration prediction model. The findings highlighted by this work will contribute, on their scale, to a better understanding of DOM fluorescence in raw sewage water (optimization of biological treatment channels) and in aquatic environments. In this sense, the usefulness of this type of work is not limited to the scientific community, but extends to managers and the operational fields
Lavaud, Aurélien. « Extraction et caractérisation de la matière organique soluble des horizons profonds d'un sol arable ». Poitiers, 2010. http://theses.edel.univ-poitiers.fr/theses/2010/Lavaud-Aurelien/2010-Lavaud-Aurelien-These.pdf.
The increase in the atmospheric CO2 concentration due to the combustion of the fossil resources and deforestation is the major environmental problems today. To store carbon and thus to decrease the concentration of CO2 emitted by human activity in the atmosphere, it would be necessary to be able to operate the carbon sinks located in the continental biosphere. The largest carbon surface reservoir of the continental biosphere is the soil, which stores 1500 Mt carbon. The potential of French soil to store carbon is currently being evaluated for the plowed horizon, i. E the first 30 cm. However, recent studies showed that a significant proportion of soil carbon is stored in horizons B and C. The precise role of soluble organic carbon or DOC (Dissolved Organic Carbon) in the stabilization and / or destabilization of carbon deep horizons is indispensable to adapt the methods of land management and cropping systems to increase the stock of carbon in soils. Despite abundant literature, studies on DOC are mainly limited to soils of forest ecosystems and especially in laboratory scale. The results were never confirmed on the ground. The overall objective of this thesis is to better define the proportion of soluble organic matter of different horizons of arable soil and indicate their main structural features. This work takes into account the importance of the mode of cultural practice and the impact of prolonged drought particularly in deep horizons. Different analytical techniques (spectrofluorimetry, chromatography size exclusion, pyrolysis GC / MS, 13C NMR) were used on waters collected at the lysimeter plates and porous candles but also HPO, TPH and HPI extracts, for characterizing the OM of deep horizons, while being based on existing work on surface water. The work showed that the OM of the deep horizons was characterized by low aromaticity, a lower molecular weight and by the presence of compound lignins types and terpenoids
Abboudi, Maher. « Réponse des bactéries marines au rayonnement ultraviolet-visible et aux modifications photochimiques de la matière organique dissoute ». Aix-Marseille 2, 2007. http://www.theses.fr/2007AIX22080.
In the marine environment, solar radiation can directly affect the activity of heterotrophic bacteria by causing various cellular damages or indirectly by modifying photochemically the dissolved organic matter (DOM). These various aspects were studied by determining experimentally the contribution of ultraviolet-B (UVR-B: 280-315 nm), ultraviolet-A (UVR-A: 315-400 nm) radiations as well as visible light (VIS: 400-700 nm) on DOM consumption by natural assemblages in various environments in the Northwestern Mediterranean Sea and by the marine bacterium, Vibrio angustum. We studied the effects of the photochemical transformations of DOM on the bacterial activity including production (BP), respiration (BR), bacterial growth efficiency (BGE) as well as the bacterial diversity, in two lagoons (Leucate and Canet) and in a coastal environment (Bay of Banyuls) in the Northwesternern Mediterranean Sea. These typical environments present large differences in the concentrations of total DOM and in colored DOM (CDOM). For the experiments, after filtration on 0,2 µm, samples were exposed during one day to the natural sunlight, then inoculated with the unexposed to light bacterial community of the same origin. The phototransformations of DOM lead to an increase of BP in the most eutrophic lagoon and to a decrease of in the mesotrophic one. These modifications of activity are associated with an increase of 120 % of the BGE in the coastal environment, and a decrease of 20-40 % in the lagoons. We also observed that the assimilation of DOM after sunlight exposure lead to modification in the structure of the total and active bacterial communities. The direct effects of the solar radiation on a natural assemblage lead to an increase of BP and BR in the column of water (from the surface until 10 m of depth) for various stations in the Mediterranean Sea. The inhibition of BP is essentially bound to UVR, and more important when the phytoplankton was eliminated from the sample, underlining the role of the phytoplanktonic excretions in the bacterial response to the UVR stress. Our results showed bacterial resilience induced by an increase of production during the night following the light exposure. The BR seems more durably affected by the solar radiation compared to BP. Generally, the solar radiation decreases the BCD and increases the BGE. The effects of the solar radiation seemed very limited in depth for the studied coastal stations, whereas the effects on BP seem measurable until depths of 8 m. These effects contrasted in the column of water were directly bound to the diffuse attenuation coefficient for downwelling UV irradiance of these various stations. To complete these data obtained in natural environment, physiological and morphological modifications of the bacterial strain Vibrio angustum were studied during growth under 4 light conditions (VIS+UVR-A+UVR-B, VIS+UVR-A, and darkness) by using a solar simulator in the laboratory. Our results suggest that the growth is severely inhibited by UVR-B and of a way moderated by UVR-A. The cells exposed to UVR-B present an important filamentation (size of cell: 42 µm with regard to the witness of size ~ 1,7 µm), with a reduced accumulation of damages DNA, and an absence of modifications in the composition in fatty acids, yet. These cells were able to recover a regular size after a darkness phase. The cells exposed to VIS and VIS UVR-A presented an important change of the fluorescence very likey in relation to the DNA modification of the topology of the genome
Soares, Pereira Caroline. « Influence de la matière organique dissoute d’origine urbaine sur la spéciation des micropolluants : de la station d’épuration au milieu récepteur ». Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1154/document.
Urban discharges alter the quality of dissolved organic matter (DMO) in receiving environments and are a major source of micropollutants. Natural MOD has been shown to influence the speciation and fate of micropollutants in both the receiving and treatment media. The objective here is to study the impact of the presence and quality of MOD on the dissolved/particulate distribution of micropollutants in aquatic systems, from the treatment plant to the receiving environment. The originality of our work is to compare the influence of a natural fulvic MOD and an urban MOD, and to work at concentrations close to concentrations in the aquatic environment. Initially, we characterized the adsorption of different types of MOD (fulvic acids (AF) and releases of STEP) on different types of particles (calcite, goethite, montmorillonite, quartz and activated carbon). In a second step, we characterized the adsorption of certain micropollutants (metallic trace elements (ETMs) and As (V), Polycyclic Aromatic Hydrocarbons (PAHs) and 13 pharmaceutical products) on particles in the absence of MOD or in the presence of MOD (AF) and releases of STEPs. Concerning the influence of MOD on the adsorption of ETMs by particles, the results obtained show a significant diversity of situations depending on the ETMs and particles considered. For goethite, we observed a decrease in adsorption in the presence of urban MOD compared to what is observed in the absence of MOD. For activated carbon, on the other hand, there is more adsorption in the presence of AF for all VTE except for Cu, which is more adsorbed in the presence of urban MOD. The various particles have generally exhibited a high adsorption capacity of PAHs, but this capacity is strongly modulated by the MOD, and this varies according to the particles. For goethite and montmorillonite, adsorption of PAHs decreased in the presence of MOD. It is stronger in the presence of urban MOD than in the presence of AF in the case of adsorption of light PAHs on goethite and adsorption of all PAHs on montmorillonite. The adsorption of heavier PAHs on goethite is lower with urban MOD than in the presence of AF. Concerning the adsorption of PAHs by the CAP, we observed a decrease in the presence of MOD, particularly in the case of urban MOD. Experiments conducted with sulfamethoxyazole did not reveal any influence of the origin of MOD on adsorption of this substance. For other pharmaceutical products, adsorption on CAP in the presence of urban MOD is generally much lower than in the mineral matrix and also lower than in the fulvic acid matrix. The abatement of these contaminants will therefore be lower in the presence of urban MOD. This can be related to the fractionation of urban MOD when adsorbed on the CAP. The results obtained show that it is essential to take into account the role of urban MOD in anthropized receptor environments (where it can be the majority in low-water environments) in order to better understand the fate of micropollutants in aquatic systems and in particular their particle/dissolved distribution. In addition, in a wastewater treatment context, the abatement of micropollutants is dependent on the nature of the present MOD, therefore, the abatement results of micropollutants observed in water purification could be significantly different in wastewater treatment
Danhiez, François-Pierre. « Relations entre les propriétés optiques de la matière organique dissoute colorée et le carbone organique dissous dans des eaux côtières aux caractéristiques contrastées ». Thesis, Littoral, 2015. http://www.theses.fr/2015DUNK0395/document.
The coastal ocean represents an important component of the global carbon cycle however its participation to the overall carbon flux is currently not well constrained. Information on DOC stock and its variability in the coastel ocean is however still very scarce and its represents a strong limitation to our current understanding of the exact role of these ecosystems in the oceanic carbon cycle. In this context, the general aims of this study was to get more insights on dissolved organic carbon dynamics in the coastal ocean through the optical properties of dissolved organic matter (CDOM) that present the advantage to be easily measured from in situ or satellite observations. In practice, in situ data gathered during several sampling cruises conducted in three constrasted continental margins (Eastern Channel, French Guiana, Vietnam) have allowed : (i) the characterization of the strong regional discrepancies in the CDOM-DOC relationships between the three coastal sites investigated, (ii) the possible use of a generalized parameterization to retrieve DOC concentrations from CDOM optical properties (estimated in situ or from ocean color remote sensing)over a large range of coastal sites dominated by terrestrial imput of DOM. A further objective of this work was to investigate the impact on DOM dynamics of the phytoplankton bloom event of Phaeocystis.globosa known to affect the coastal waters of the eastern English Channel during the spring period. In practice, this DOM production was investigated during a 45 days mesocom experiment coupled to field survey data (2012-1014) leading to the identification of an optical marker of this marine CDOM production (i.e. S320-412). We further demonstrated that this optical parameter provides useful information to enhance our ability to retrieve DIC 1 from CDOM optical properties in a context of an algal bloom event
Patel-Sorrentino, Nathalie. « Fluorescence et évolution de la matière organique dissoute et colloi͏̈dale dans les zones de mélange du bassin amazonien ». Aix-Marseille 3, 2000. http://www.theses.fr/2000AIX30015.
This study concerns the dissolved and colloidal organic matter in the mixing zones of the Amazon basin. The separation by Sequential Tangential UltraFiltration (STUF) on site indicates an organic matter distribution in the particulate and dissolved domains, respectively, for the black and white waters. It is also shown that the Rio Negro does not produce a simple diluting effect, his waters play a key role in the composition and distribution of organic carbon of the Amazon. The sampling of the Purus River, a Southern tributary of the Rio Solimões, shows a very large concentration (>80% of the TOC concentration) in the dissolved phase. During the mixing of black and white waters, the waters of the Rio Solimões push and go under the Rio Negro ones. An insight into the nature and characterisation of organic matter in tropical river systems is then developed. The exploitation of Excitation and Emission Matrix Fluorescence (EEMF) allows the differentiation of the fluorophores A and C which are observed for all the samples and the fluorophore B which seems to be characteristic of the black waters of the amazonian basin
Boukra, Mohamed-Amine. « Caractérisation intégrée de la matière organique dissoute : recherche d'empreintes physico-chimiques pour tracer les sources de pollutions anthropiques ». Electronic Thesis or Diss., Lyon 1, 2023. http://www.theses.fr/2023LYO10094.
Anthropogenic activities at the scale of a watershed can be very numerous (e.g. agricultural practices, industries, transport, and tourism). These activities generate pressures that result in the input of pollutants to the watercourse (e.g. major elements, organic micropollutants, trace metals). The identification of these sources of pollutants in watercourses remains a challenge to date. Organic matter in its dissolved fraction (DOM) constitutes a complex mixture of molecules whose composition and physicochemical properties depend on its origin, whether natural or anthropogenic, terrigenous or autochthonous, diffuse or point source. Because of its ubiquity, the DOM present in the rivers could be used as a tracer of the anthropic activities and thus of the sources of pollutants at the scale of a catchment. In this context, the objective of this thesis is to identify markers based on physico-chemical properties of DOM (that are characteristic of natural (e.g. terrigenous inputs, autochthonous production) and anthropogenic (e.g. wastewater treatment plant discharges, urban runoff, agriculture and livestock activities) sources at the watershed scale. For this purpose, an original database was built with more than 130 water samples representative of these different sources and analyzed with a wide range of analytical techniques (dissolved organic carbon determination, analysis by UV-Visible spectroscopy and fluorescence excitation-emission, analysis by steric exclusion chromatography coupled with UV and fluorescence detection - HPSEC/UV-fluorescence - , and molecular analysis by liquid chromatography coupled with high resolution mass spectrometry - LC-HRMS - ). The exploitation of the database allowed to improve the characterization of DOM with the identification of new optical (HPSEC/UV-fluorescence) and molecular (LC-HRMS) indicators. A protocol for processing complex data from non-targeted LC-HRMS analysis was developed and validated using quality control in order to extract the most relevant molecular compounds to differentiate DOM sources. This work also validated a sampling methodology specific to land-based diffuse sources in relation to land use to build their footprints at the watershed scale. Finally, the integrated multi-analytical and multi-source approach developed in the framework of the thesis allowed the construction of specific fingerprints of the selected sources of DOM (natural, anthropogenic, diffuse, point). The results of this work clearly show that DOM can be considered as a tracer of the origin of the water masses and the associated pollutions in the rivers
Bressac, Matthieu. « Apports atmosphériques à l'océan : devenir du fer atmosphérique, interactions des particules avec la matière organique et conséquences sur l'export de carbone ». Paris 6, 2013. http://www.theses.fr/2013PA066016.
Cette thèse a pour but d’étudier l’impact des apports atmosphériques sur les cycles biogéochimiques et l’export de carbone à l’océan profond. Deux approches expérimentales complémentaires d’ensemencement artificiel au sein d’un assemblage naturel et en condition abiotique ont permis de démontrer l’importance des processus d’agrégation entre les particules lithogéniques et la matière organique dissoute (MOD) et ont confirmé le pouvoir « ballast » attribué à ces particules. Nous avons ainsi pu démontrer que le flux de carbone organique particulaire (COP) associé à ces particules pouvait représenter une part importante du flux global de COP engendré par ces dépôts atmosphériques. Cette « pompe à carbone lithogénique » peut donc être considérée comme une composante majeure de l’export de carbone dans les régions océaniques fortement soumises aux dépôts atmosphériques. L’influence de la MOD et le rôle des différents processus post-dépositionnels sur le devenir du fer dissous (DFe) d’origine atmosphérique dans l’eau de mer ont également été étudiés. De fortes interconnexions entre les processus post-dépositionnels, contrôlées par la MOD, ont induit une large gamme de dissolution du fer d’origine atmosphérique (un ordre de grandeur) dans des conditions biogéochimiques contrastées. Ces variations saisonnières sont telles que la non-prise en compte de ces processus post-dépositionnels fausse notre compréhension du rôle des apports atmosphériques sur le cycle du fer. Ainsi, les flux de DFe ne sont pas linéairement reliés aux flux atmosphériques démontrant l’inadéquation de l’utilisation d’une valeur absolue de solubilité du fer pour paramétrer les flux de fer biodisponible à l’océan
Coquillé, Nathalie. « Influence de la matière organique dissoute naturelle et d'herbicides, seuls et combinés, sur des microalgues marines et d'eau douce ». Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0564/document.
Microalgae are at the basis of aquatic food webs and may be the indirect target of herbicidesfrom agricultural and urban uses. They also interact with other compounds from their environment such asnatural dissolved organic matter (DOM), which can itself interact with herbicides. This thesis aimed tostudy, in laboratory controlled conditions, the influence of natural DOM on herbicide toxicity to microalgaeby using monospecific, non-axenic cultures. The experiments included: natural freshwater and marineDOM, three herbicides (irgarol, diuron and S-metolachlor) singly and in mixtures, two freshwatermicroalgae (Gomphonema gracile and Sphaerellopsis sp.) and two marine microalgae (Chaetoceroscalcitrans and Tetraselmis suecica). Effects were evaluated on microalgae growth, photosyntheticefficiency and relative lipid content. At the same time, changes in chemical environment over theexperiments were measured through DOM composition and properties, as well as the concentrations inherbicides and their metabolites. The results of this work, which consider for the first time natural DOM asa whole, interacting with microalgae, their associated bacteria and herbicides, demonstrate the key roleplayed by DOM in (i) the growth stimulation of four microalgae (and in return the DOM changes inducedby microalgae), (ii) the modulation of herbicide toxicity and suggest (iii) the ability of Sphaerellopsis sp.and/or its associated bacteria to biodegrade diuron in non-axenic conditions
Ouro-Boya, Boukari Sahidou. « Evaluation de l'état d'une eau de rivière par analyse multidimensionnelle utilisant des paramètres caractéristiques de la matière organique dissoute ». Poitiers, 2004. http://www.theses.fr/2004POIT2255.
This study aims to show the possibilities offered by the PCA in the description of the physicochemical quality of a river and to evaluate the anthropic contribution of the dissolved organic matter (DOM) to the degradation of this quality. Being based on an analytical follow-up in 13 stations of Vienne river, it was shown that the study of the bivaried correlations allows to reveal perturbations of the environment, by the organic discharges. Various PCA made it possible to specify with a good objectivity the spatial and temporal changes in water quality in Vienne river. In addition, dispersion in the PCA plan of the individuals representative of the same station can be used to evaluate the disturbances related to the anthropic contributions. In order to acquire a better knowledge of the evolution of the DOM of a rivers, research were carried out on the study of OM extracts isolated through various analytical techniques from characterization
Boutrif, Mehdi. « Dégradation de la matière organique dissoute de haut poids moléculaire par les communautés procaryotiques des zones méso- et bathypélagique ». Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4040.
This main objective of this work is the study of interactions between prokaryotic compartments of meso-and bathypelagic zones with different size classes of dissolved organic carbon (DOC). Several measurements of monomers assimilation (3H-Glucose), of complex molecules degradation (3H-EPS and HMW-DOC) and prokaryotic heterotrophic production were realized through the water column of NW Mediterranean Sea (Gulf of Lion, DYFAMED and ANTARES station) and NE Atlantic Ocean (PAP site). During these studies, all measurements realized below 1000 m depth, were carry out under in situ condition of hydrostatic pressure (> 10 MPa, HP) and compared to their decompressed counterpart measurements, realized at atmospheric pressure (0.1 MPa, ATM). These coupled measurements determine the role of hydrostatic pressure on deep sea microbial activity following the Pressure effect (Re) ration (=HP measurement / ATM measurement). The results show that microbial activities measured under HP condition during stratified water period, were more important than those measured under ATM condition (mean Pe = 4.01, n=120), and confirm the abilities of deep sea prokaryotes to degrade complex organic molecules. Moreover, the cell-specific activity of deep sea prokaryotes in 3H-EPS degradation are 6 time more active than the surface, indicating the ability of autochthonous deep sea prokaryotes to degrade complex molecules under high conditions of pressure
Breitenstein, Johann. « Application de la chromatographie d'exclusion stérique multi-détection à l'étude de la spéciation de la matière organique dissoute en milieu estuarien et côtier Measuring dissolved organic matter in estuarine and marine waters : size-exclusion chromatography with various detection methods, in Environmental Chemistry 15(7), October 2018 ». Thesis, Brest, 2019. http://www.theses.fr/2019BRES0074.
Dissolved organic matter (DOM) is one of the most important vector of carbon to the ocean.However, DOM is deeply altered during its transit through estuarine waters and its residence time in Coastal waters. The purpose of this thesis is to bring new insights on the DOM composition, role in biogeochemical cycles during land-sea transfer and fate in Coastal areas. DOM analysis was performed with a global and semi-specific tool: size-exclusion chromatography multi-detection (SEC-mDEC), which allow the separation of DOM into six size fractions of different nature. Dynamics of these compounds are studied seasonally in the Aulne estuary and the bay of Brest. The coupling between SEC-mDEC and 3D fluorescence was studied in the estuary.Initially design for freshwater analysis, the adapted SEC-mDEC for estuarine and marine water analyses permitted the demonstration that DOM is involved in several biogeochemical processes. In the Aulne estuary, DOM tracks the contribution of both riverine and marine sources. Substantial changes are made to the DOM by microorganisms and flocculation processes upstream. In the Bay of Brest, ail fractions enable to design a reactivity continuum from the bacterial degradation of the phytoplanktonic bloom.Results demonstrate that the single use of the global dissolved organic carbon is not enough to constrain DOM dynamic in the land-sea continuum
Marie, Lauriane. « Composition, transfert et dynamique de la matière organique dissoute (MOD) dans les eaux fluviales et estuariennes : impact des activités agricoles ». Thesis, Brest, 2016. http://www.theses.fr/2016BRES0101/document.
In watersheds under strong agricultural pressure, manuring activities, particularly animal farming, are the main source of dissolved organic matter (DOM). However, the composition, the role and the fate of this DOM have been poorly studied. This study focuses on the sources, dynamics and transformation of the DOM and its constituents in riverine and estuarine systems affected by different agricultural practices. The analysis of DOM was performed using two recent and innovative analytical techniques: (i) an electrochemical method (DP-CSV), allowed us to characterize simultaneously three dissolved organic compounds: glutathione (GSH-like), thioacetamide (TA-like), and fulvic acids (FA-like), (ii) a size exclusion liquid chromatography coupled to an carbon, nitrogen and UV detector (LC-OCD-OND-UVD) allowed the DOM pool to be subdivided into 6 major sub-fractions. Relative to the pristine river, concentrations of organic compounds were found to be 1.5 to 4 times higher in impacted systems. These anomalies are related to the agricultural pressure and also to the type of livestock. Our results also showed that the seasonal variations were controlled by different processes: soil washing-out during high precipitation events for FA-like compounds which represent the major part of DOM, formation in deep horizons then rising of groundwater for TA-like compounds and a pedogenic and aquatic origin for GSH-like compounds. Along the salinity gradient, GSH-like and FA-like displayed a conservative behaviour whereas TA-like do not behave conservatively with important removals
Djaoudi, Kahina. « Rôle de l'apport atmosphérique sur les processus de biodégradation et la stoechiométrie de la matière organique dissoute en mer Méditerranée ». Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0074/document.
Establishing a link between atmospheric deposition and the dissolved organic matter (DOM) pool in the Mediterranean Sea is currently hampered by: (1) a poor knowledge on the surface dissolved phosphate (P) pool, mainly due to low concentrations of dissolved inorganic phosphate (DIP), (2) a critical lack of data on atmospheric fluxes of organic C, N and P and (3) the lack of information on their bioavailability. This PhD thesis aimed at filling these gaps. (1) Relying upon a sensitive determination of DIP, the coverage of the valid dissolved organic phosphate data was enhanced up to 70%, revealing a vertical pattern in the dissolved phosphate biogeochemistry in surface waters. (2) Atmospheric fluxes of soluble organic C, N and P were quantified and were 59 mmol C m-2 yr-1, 16.4 mmol N m-2 yr-1 and 23.6 μmol P m-2 yr-1, respectively. The contribution of the organic fraction to the total atmospheric fluxes of N and P was of 40% and 25%, respectively. The labile fraction of atmospheric deposition of organic phosphate was also quantified during the study period and showed a wide variability, ranging from 0 to 97%. (3) The bioavailability of atmospheric organic matter was experimentally assessed. DOM contained in a Saharan rainwater could support the activity of marine heterotrophic bacteria, with an amount of labile carbon of 29%. The labile fraction of carbon contained in desert dust and anthropogenic aerosols was also substantial, 26 ± 2% and 15 ± 5%, respectively. The results obtained from this PhD thesis emphasize the non-negligible character of atmospheric deposition and highlight the key role that this external source could have on the oceanic DOM cycle
Djaoudi, Kahina. « Rôle de l'apport atmosphérique sur les processus de biodégradation et la stoechiométrie de la matière organique dissoute en mer Méditerranée ». Electronic Thesis or Diss., Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0074.
Establishing a link between atmospheric deposition and the dissolved organic matter (DOM) pool in the Mediterranean Sea is currently hampered by: (1) a poor knowledge on the surface dissolved phosphate (P) pool, mainly due to low concentrations of dissolved inorganic phosphate (DIP), (2) a critical lack of data on atmospheric fluxes of organic C, N and P and (3) the lack of information on their bioavailability. This PhD thesis aimed at filling these gaps. (1) Relying upon a sensitive determination of DIP, the coverage of the valid dissolved organic phosphate data was enhanced up to 70%, revealing a vertical pattern in the dissolved phosphate biogeochemistry in surface waters. (2) Atmospheric fluxes of soluble organic C, N and P were quantified and were 59 mmol C m-2 yr-1, 16.4 mmol N m-2 yr-1 and 23.6 μmol P m-2 yr-1, respectively. The contribution of the organic fraction to the total atmospheric fluxes of N and P was of 40% and 25%, respectively. The labile fraction of atmospheric deposition of organic phosphate was also quantified during the study period and showed a wide variability, ranging from 0 to 97%. (3) The bioavailability of atmospheric organic matter was experimentally assessed. DOM contained in a Saharan rainwater could support the activity of marine heterotrophic bacteria, with an amount of labile carbon of 29%. The labile fraction of carbon contained in desert dust and anthropogenic aerosols was also substantial, 26 ± 2% and 15 ± 5%, respectively. The results obtained from this PhD thesis emphasize the non-negligible character of atmospheric deposition and highlight the key role that this external source could have on the oceanic DOM cycle
Thibault, Alexandre. « Dynamique de la matière organique dans la Seine : approche globale et moléculaire ». Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS284.
Estuaries are important ecosystems from environmental and economical point of views and are the place of numerous transformations of organic matter (OM). The dynamics of OM in estuarine systems is complex and was only rarely investigated at the structural or molecular level. The aim of this study was to constrain the sources and fate of the OM in the Seine Estuary. The spatiotemporal dynamics of the OM along the estuary was investigated by comparing the bulk (elemental and isotopic composition), structural (solid state 13C nuclear magnetic resonance) and molecular (lipids and thermochemolysis) features of the different pools of OM – dissolved OM (DOM), particulate OM (POM) and sediment OM collected during five sampling campaigns. All analyses show that each compartment has different chemical properties: DOM is enriched in degraded aquatic OM, while POM and sediment OM are enriched in terrigenous OM. The maximum turbidity zone has an impact on OM quality with a high bacterial activity leading to the degradation of terrigenous OM and a higher proportion of aquatic OM. This study shows that sediment OM does not reflect the composition of the POM in the water column and is enriched in terrigenous OM. Moreover, when the sediment is aging, the proportion of terrigenous OM is increasing
Matar, Zeinab, et Zeinab Matar. « Influence de la matière organique dissoute d'origine urbaine sur la spéciation et la biodisponibilité des métaux dans les milieux récepteurs anthropisés ». Phd thesis, Université Paris-Est, 2012. http://pastel.archives-ouvertes.fr/pastel-00806323.
Mejbri, Rakha. « Fractionnement et caractérisation de la matière organique dissoute dans les lixiviats de décharges d'ordures ménagères : effets du traitement par lagunage aéré ». Limoges, 1997. http://www.theses.fr/1997LIMO0031.
Matar, Zeinab. « Influence de la matière organique dissoute d'origine urbaine sur la spéciation et la biodisponibilité des métaux dans les milieux récepteurs anthropisés ». Thesis, Paris Est, 2012. http://www.theses.fr/2012PEST1151/document.
This thesis was carried out on the framework of the OPUR and Piren-Seine programs. The main objectives were to improve the current knowledge on the influence of combined sewer overflows (CSO) on metal speciation and bioavailability in urban aquatic system. Indeed, the impact of heavy metals in the receiving environment on the life of microorganisms depends on a portion of their total concentrations but also and especially of their bioavailability. It is generally recognized that the bioavailable heavy metals to microorganisms is dissolved free. The CSO's will be able to significantly change the content and bioavailability of heavy metals in the environment in so far as these discharges are heavily loaded with dissolved organic matter (DOM) which will considerably influence with the DOM already present in course of water the speciation of metals in the environment given its ability to complex metals and its tendency to decrease their bioavailability. The understanding of the influence of DOM on trace metal speciation and bioavailability required that the chemical composition of DOM, more exactly its binding sites should be well understood. Therefore, one part of this research focused on the characterization of DOM of natural and urban origin by fractionation according to the criteria of polarity. A finer characterization was performed using functional analyses that were of prime importance to better understand the influence of DOM on copper speciation and bioavailability. Alongside the characterization study of the DOM, this work aims to better understand the role of urban DOM in particular hydrophilic fraction on the speciation and bioavailability of copper. To accomplish these objectives, the technique such as potentiometry with ionic selective electrode and bioassay such as an acute toxicity test (Daphnia magna) were performed in order to: - Study the copper binding by DOM in order to give some binding parameters of hydrophilic DOM and to better predict the fate of the trace metal. - Evaluate the protective role of urban DOM on copper bioavailability. Results showed some particular characteristics of urban DOM such as a high proportion of hydrophilic DOM, i.e. a low hydrophobicity and a low degree of aromaticity underlying the low refractory character of this DOM. Nevertheless a higher content of various functional groups was determined in urban DOM than in natural DOM. A very high content of proteinaceous structures was particularly identified in urban DOM. Binding experiments revealed a higher content of binding sites in urban discharges than in natural DOM and these sites are strongly correlated to amino groups. The approach used to evaluate copper bioavailability depicted a protective role of DOM to the organisms Daphnia magna(...)
Trudel, Geneviève. « Sources, biodisponibilité et transformation de la matière organique dissoute en zone littorale du lac Saint-Pierre : importance de la connectivité hydrologique ». Thèse, Université du Québec à Trois-Rivières, 2007. http://depot-e.uqtr.ca/1949/1/030000415.pdf.
Blanchet, Marine. « Modifications métaboliques et structurelles des communautés de bactéries marines exposées à différentes qualités de matière organique ». Electronic Thesis or Diss., Paris 6, 2015. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2015PA066092.pdf.
Heterotrophic bacterial communities in marine environment are exposed to a heterogeneous mixture of dissolved organic compounds with different bioavailability that may control both their activities and their composition. In the frame of this thesis, we studied the response of different coastal bacterial communities to the single or combined addition of various natural dissolved organic matter (DOM) photo-oxidized or not, presenting different bioavailability characteristics. Firstly, we studied the effects of the addition of highly bioreactive DOM derived from jellyfish on bacterial activities and community structure in a Mediterranean coastal lagoon. We observed that resilience of the bacterial community after the addition of DOM from the jellyfish was higher for metabolic functions than diversity, suggesting that jellyfish blooms can induce durable changes in the bacterial community structure in coastal lagoons. Secondly, we investigated the occurrence of priming effect (increase in microbial degradation of refractory DOM upon the addition of labile DOM) on coastal marine environments. Experiments with single or combined additions of recalcitrant and labile DOM sources were performed with a Mediterranean and a Patagonian fjord bacterial communities. In both cases we observed a greater effect of combined addition on bacterial community composition. However we did not observe an increase in recalcitrant DOM degradation of recalcitrant DOM following the addition of labile compounds, suggesting that priming effect did not occur during our experiments. Finally, we studied the impact of contrasted DOM (i.e. recalcitrant riverine DOM, labile phytoplankton-derived DOM) photodegradation on coastal bacterial communities activity and composition. We observed that photodegradation of phytoplankton-derived DOM led to a lower bacterial growth and changes in bacterial community diversity, in favour of Alphaproteobacteria
Retamal, Leira. « Effet optique de la matière organique dissoute colorée sur la production primaire dans des systèmes d'estuaires nordiques : qualité, quantité et changements climatiques ». Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24859/24859.pdf.
Para, Julien. « Etude de la Matière Organique Dissoute Chromophorique et du rayonnement solaire (UV-visible) dans les eaux de surfaces côtières méditerranéennes et articques ». Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22041/document.
To understand, characterize, and predict the evolution of oceanic biogeochemical cycles in relation to the global climate change, it is necessary to better understand the dynamics of organic matter (OM). In this context, the overall objective of this thesis was to get more insights chromophoric dissolved fraction of OM (CDOM) dynamics in surface Mediterranean and Arctic coastal waters and to determine the impact on attenuation of ultraviolet (UVR) and visible (PAR) underwater radiation. For this, the study of optical properties of absorbance and fluorescence of CDOM, coupled with atmospheric and underwater radiometric measurements, were made during a seasonal cycle in the Bay of Marseille (SOFCOM station), and in the Beaufort Sea during summer 2009. The Bay of Marseilles is characterized by low amounts of CDOM (aCDOM(350) = 0.10 ± 0.02 m-1), particularly in end summer stratification period due to the intensity of the solar irradiance, enriched in UVR-B, which degrades and bleaches CDOM (SCDOM = 0.023 ± 0.003 nm-1). In this highly urbanized coastal area, the dynamics of CDOM are driven by biotic processes (in situ biological production and within the Rhône River plume) and abiotic (photo-bleaching and mixing). Our results showed that CDOM is mostly of autochthonous origin, even during Rhône plume intrusion events (photo-degradation of terrestrial CDOM during the transit). During bloom periods, the CDOM consists mainly of a recent type protein (peak T), which preferentially absorbs in the short UVR. These pulses of recent CDOM are superimposed on a persistent background of CDOM mainly composed of aged material, humic-type (peaks M and C), which absorbs UVR and PAR. Over the Canadian shelf of the Beaufort Sea, CDOM is highly abundant (aCDOMmax (350) = 6.36 m-1) and strongly influenced by allochthonous inputs from the Mackenzie (peaks A-C and M) decreasing conservatively with salinity. In marine waters (salinity> 25), CDOM had lower concentrations (aCDOM(350) = 0.21 ± 0.13 m-1) and originated from a recent in situ biological production favored by upwelling and brine injections (peaks B-T and M). Surprisingly, the main source of the marine humic-like component (peak M) was not autochthonous. This material originates from allochthonous inputs from the Mackenzie River, which traverses numerous lakes where intense biological activity occurs. We suggest that this activity is mainly due to the macrophytes development, which may in part explain the origin of the peak M. This source of organic allochthonous CDOM coupled to other processes such as photobleaching and absorption on the particles of terrestrial CDOM, could explain the high values of SCDOM (≈ 0.020 nm-1) recorded in the Mackenzie during summertime
Sánchez-Pérez, Elvia Denisse. « Rôle des mécanismes biotiques et abiotiques dans la dynamique de la matière organique dissoute dans les écosystèmes marins pélagiques (Méditerranée Nord Occidentale) ». Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066474/document.
Chromophoric dissolved organic matter (CDOM) is a major fraction of dissolved organic matter (DOM). CDOM absorbs light over a broad range of ultraviolet (UV-R) and visible wavelengths. A small fraction of CDOM can emit fluorescence when excited by ultraviolet radiation; so called fluorescent dissolved organic matter (FDOM). CDOM plays a key role in regulating light penetration into the ocean, absorbing high-energy electromagnetic spectrum (visible and ultraviolet light) waves. On one hand, it protects aquatic organisms of potential photo-damage; in the other hand it induces a negative effect by reducing light for photosynthesis. The optical properties of the CDOM are sensitive to biological (biotic) and physical (abiotic) processes and for this reason the colored matter can provide valuable information about the biogeochemical processes in aquatic environments. CDOM monitoring in Mediterranean coastal areas has shown different temporal trends, which go from weak to strong seasonality. Interestedly, these temporal trends were uncoupled with those of the total dissolved organic carbon. In temperate areas, episodic meteorological events can induce much more abrupt changes in the littoral than in the open sea, where changes tend to be more gradual along the year. In addition, the input of nutrients and pollutants in coastal areas is strongly influenced by the anthropogenic activity on land, and those inputs do not necessarily follow seasonal trends. In the present study, weekly and monthly samplings were performed to investigate the temporal variability in SOLA and MOLA stations, respectively. The fluctuation of different fractions of dissolved organic matter (DOM) was evaluated from February 2013 to April 2014 and referred to long time-frame databases of SOLA and MOLA stations. Inorganic nutrients and chlorophyll shown the classical seasonal patterns, with a winter period characterized by an enrichment of surface waters favoring the spring bloom, followed by a calm period that allows the summer stratification and the depletion of nutrients in the photic zone. The stratification extended until autumn winds and low temperatures eroded the thermocline. In contrast, colored DOM fractions did not follow a clear temporal trend. Interestingly, dissolved organic carbon (DOC) exhibited the highest variability in summer, when the rest of parameters showed minimum variations. To explain this mismatch we proposed a sequence of abiotic and biotic phenomena driving the DOC dynamics. In the suggested conceptual frame, DOC dynamics depended strongly on episodic meteorological events (winds, rains, etc.) along the year, except in summer, where the biological factors were more relevant. In order to better understand the influence of biological factors, we examined the temporal trends of phytoplankton composition in relation to those of the different colored DOM fractions. We found that both phytoplankton and CDOM were strongly influenced by abiotic factors such as the intrusions of fresh waters, the vertical mixing due to convection and the light exposure. However we did not find a correlation between any of the CDOM fractions and any of phytoplankton groups. In addition, we use the dust deposition database of ADEPT project (ICM-CSIC, Barcelona) to investigate the potential role of atmospheric deposition in the CDOM temporal variability, and also performed two dust addition experiments with natural plankton communities collected in the Catalan coast
Sánchez-Pérez, Elvia Denisse. « Rôle des mécanismes biotiques et abiotiques dans la dynamique de la matière organique dissoute dans les écosystèmes marins pélagiques (Méditerranée Nord Occidentale) ». Electronic Thesis or Diss., Paris 6, 2015. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2015PA066474.pdf.
Chromophoric dissolved organic matter (CDOM) is a major fraction of dissolved organic matter (DOM). CDOM absorbs light over a broad range of ultraviolet (UV-R) and visible wavelengths. A small fraction of CDOM can emit fluorescence when excited by ultraviolet radiation; so called fluorescent dissolved organic matter (FDOM). CDOM plays a key role in regulating light penetration into the ocean, absorbing high-energy electromagnetic spectrum (visible and ultraviolet light) waves. On one hand, it protects aquatic organisms of potential photo-damage; in the other hand it induces a negative effect by reducing light for photosynthesis. The optical properties of the CDOM are sensitive to biological (biotic) and physical (abiotic) processes and for this reason the colored matter can provide valuable information about the biogeochemical processes in aquatic environments. CDOM monitoring in Mediterranean coastal areas has shown different temporal trends, which go from weak to strong seasonality. Interestedly, these temporal trends were uncoupled with those of the total dissolved organic carbon. In temperate areas, episodic meteorological events can induce much more abrupt changes in the littoral than in the open sea, where changes tend to be more gradual along the year. In addition, the input of nutrients and pollutants in coastal areas is strongly influenced by the anthropogenic activity on land, and those inputs do not necessarily follow seasonal trends. In the present study, weekly and monthly samplings were performed to investigate the temporal variability in SOLA and MOLA stations, respectively. The fluctuation of different fractions of dissolved organic matter (DOM) was evaluated from February 2013 to April 2014 and referred to long time-frame databases of SOLA and MOLA stations. Inorganic nutrients and chlorophyll shown the classical seasonal patterns, with a winter period characterized by an enrichment of surface waters favoring the spring bloom, followed by a calm period that allows the summer stratification and the depletion of nutrients in the photic zone. The stratification extended until autumn winds and low temperatures eroded the thermocline. In contrast, colored DOM fractions did not follow a clear temporal trend. Interestingly, dissolved organic carbon (DOC) exhibited the highest variability in summer, when the rest of parameters showed minimum variations. To explain this mismatch we proposed a sequence of abiotic and biotic phenomena driving the DOC dynamics. In the suggested conceptual frame, DOC dynamics depended strongly on episodic meteorological events (winds, rains, etc.) along the year, except in summer, where the biological factors were more relevant. In order to better understand the influence of biological factors, we examined the temporal trends of phytoplankton composition in relation to those of the different colored DOM fractions. We found that both phytoplankton and CDOM were strongly influenced by abiotic factors such as the intrusions of fresh waters, the vertical mixing due to convection and the light exposure. However we did not find a correlation between any of the CDOM fractions and any of phytoplankton groups. In addition, we use the dust deposition database of ADEPT project (ICM-CSIC, Barcelona) to investigate the potential role of atmospheric deposition in the CDOM temporal variability, and also performed two dust addition experiments with natural plankton communities collected in the Catalan coast
Falantin, Cécilia. « Influence du soufre sur la complexation de cations métalliques par la matière organiques dissoute : du milieu naturel au modèle ». Electronic Thesis or Diss., Lille 1, 2017. http://www.theses.fr/2017LIL10173.
Organic matter (OM) of aquatic systems is a complex mixture of macromolecules which has a high capacity for interaction with metals and thus modifies their bioavailability. There is a wide variety of complexing sites available to bind metal ions. The objective of this work is to have a better understanding of the process of complexation of certain cations by different oxygenated and sulfur-containing chelating sites of OM. To achieve this objective, three categories of OM were studied: dissolved OM (DOM) from fresh water, fractionated DOM and model compounds of OM. In each of these classes, sulfur and oxygen samples were compared to evaluate the influence of the presence of sulfur-containing sites on the complexing properties of metals by OM. The studies were conducted using chemometric and quantum chemistry methods combined with electronic spectroscopy techniques. The results obtained showed that the MON, characterized initially, sees its complexing capacities increase with the concentration of sulfur. Sulfur appears to have an effect on the complexing power, but no spectral information has been able to prove the presence of complexes obtained from sulfur-containing sites. The use of model molecules has shown the higher complexing power of the sulfur-containing sites compared to the oxygenated one for a large number of cations and for two types of functions. It has also been shown that a dithiol function has a greater binding power of metals than a hydroxy-thioketone function
Jacquin, Céline. « Caractérisation de la Matière Organique Dissoute (DOM) et de ses interactions avec une séparation par membrane pour l'amélioration du contrôle des BioRéacteurs à Membranes (BàM) ». Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT063/document.
Membrane BioReactors (MBR) are suitable technology to face one of the major 21th century challenges : wastewater reuse.Combining biological treatment with membrane separation step, MBR produce reusable water through total physical disinfection. Nevertheless, it democratization is limited by membrane fouling that is mainly caused by Dissolved Organic Matter (DOM) compounds when the system is optimized.In order to understand and control membrane fouling, tools were developed to identify DOM compounds responsible for this phenomenon.Thus, this PhD work, focused on studying the DOM taken from two MBR fed with real wastewater: a full-scale MBR treating urban wastewater (La Grande-Motte wastewaster treatment plant) and a lab-scale MBR treating urine from source-separated toilets.Dissolved organic matter collected in the first MBR was fractionated by size and hydrophobicity to identify fractions’ fouling mechanisms. Then, filtration tests performed on the different fractions highlighted the role of colloids (proteins) in external fouling (cake) and humic substances in internal fouling. Filtration tests were combined with fluorescence3D (3DEEM) measurements, which is a quick identification method with an easy extracted signal, allowing to define qualitative indicators for both foulants classes.After, coupling 3DEEM with a size separation and quantification method (LC-OCD), qualitative signals from foulants indicators were calibrated. Thus, using 3DEEM it was possible to obtain a quantitative and size information about DOM foulants. These new indicators were used on-site and allowed establishing links between DOM and operating parameters or influent quality, which is necessary for DOM global control and its impact on membrane fouling. These tools highlight the potentiality for 3DEEM on-line application for separation step monitoring, control and optimization
Paillard, Hervé. « Etude de la minéralisation de la matière organique dissoute en milieu aqueux dilué par ozonation, oxydation avancée O3/H2O2 et ozonation catalytique hétérogène ». Poitiers, 1994. http://www.theses.fr/1994POIT2357.
Martias, Chloé. « Dynamique de la matière organique dissoute colorée et fluorescente en zone lagonaire tropicale dans le Pacifique Sud (Nouvelle Calédonie) : influences climatiques et anthropogéniques ». Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0133/document.
New Caledonia (South-West Pacific) is a tropical area under strong environmental pressure (climate change and local anthropogenic forcing). The aim of this thesis was to gain a better understanding of the colored (CDOM) and fluorescent (FDOM) dissolved organic matter dynamic in the New Caledonia Lagoon where strong ultramafic erosion pressure is associated with trace metals (i.e., nickel, manganese and cobalt). 3D spectrofluorimetry was used to characterize the CDOM/FDOM. The West and East coasts were sampled during one year and a half in a context of El Niño (2015-2016), interrupted by strong rainy events (storms) and during CALIOPE 3 cruise (East coast). A parallel factor analysis (PARAFAC) of EEMF led to the identification of 5 fluorophores: marine humic-like, 2 tyrosine-like and tryptophan-like peaks (T2 peak) from the biological balance between phytoplankton and bacterioplankton and a terrestrial humic-like from rivers draining caledonian coast. The CDOM signal at 350 and 442 nm had a strong dependency on river inputs accentuated during storms and revealed photodegraded CDOM. The FDOM signal in the East showed a seasonal cycle (wet/dry season) contrary to the West coast depending on sporadic rainy events. Data acquired during the CALIOPE 3 were coupled with trace metal concentrations, biogeochemical parameters, and plankton communities. Some fluorophores displayed a preferential association with nickel and cobalt. The complexation capacities of these fluorophores toward trace metals were revealed by a quenching experiment that allowed to derive complexation constants
Martias, Chloé. « Dynamique de la matière organique dissoute colorée et fluorescente en zone lagonaire tropicale dans le Pacifique Sud (Nouvelle Calédonie) : influences climatiques et anthropogéniques ». Electronic Thesis or Diss., Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0133.
New Caledonia (South-West Pacific) is a tropical area under strong environmental pressure (climate change and local anthropogenic forcing). The aim of this thesis was to gain a better understanding of the colored (CDOM) and fluorescent (FDOM) dissolved organic matter dynamic in the New Caledonia Lagoon where strong ultramafic erosion pressure is associated with trace metals (i.e., nickel, manganese and cobalt). 3D spectrofluorimetry was used to characterize the CDOM/FDOM. The West and East coasts were sampled during one year and a half in a context of El Niño (2015-2016), interrupted by strong rainy events (storms) and during CALIOPE 3 cruise (East coast). A parallel factor analysis (PARAFAC) of EEMF led to the identification of 5 fluorophores: marine humic-like, 2 tyrosine-like and tryptophan-like peaks (T2 peak) from the biological balance between phytoplankton and bacterioplankton and a terrestrial humic-like from rivers draining caledonian coast. The CDOM signal at 350 and 442 nm had a strong dependency on river inputs accentuated during storms and revealed photodegraded CDOM. The FDOM signal in the East showed a seasonal cycle (wet/dry season) contrary to the West coast depending on sporadic rainy events. Data acquired during the CALIOPE 3 were coupled with trace metal concentrations, biogeochemical parameters, and plankton communities. Some fluorophores displayed a preferential association with nickel and cobalt. The complexation capacities of these fluorophores toward trace metals were revealed by a quenching experiment that allowed to derive complexation constants
Falantin, Cécilia. « Influence du soufre sur la complexation de cations métalliques par la matière organiques dissoute : du milieu naturel au modèle ». Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10173.
Organic matter (OM) of aquatic systems is a complex mixture of macromolecules which has a high capacity for interaction with metals and thus modifies their bioavailability. There is a wide variety of complexing sites available to bind metal ions. The objective of this work is to have a better understanding of the process of complexation of certain cations by different oxygenated and sulfur-containing chelating sites of OM. To achieve this objective, three categories of OM were studied: dissolved OM (DOM) from fresh water, fractionated DOM and model compounds of OM. In each of these classes, sulfur and oxygen samples were compared to evaluate the influence of the presence of sulfur-containing sites on the complexing properties of metals by OM. The studies were conducted using chemometric and quantum chemistry methods combined with electronic spectroscopy techniques. The results obtained showed that the MON, characterized initially, sees its complexing capacities increase with the concentration of sulfur. Sulfur appears to have an effect on the complexing power, but no spectral information has been able to prove the presence of complexes obtained from sulfur-containing sites. The use of model molecules has shown the higher complexing power of the sulfur-containing sites compared to the oxygenated one for a large number of cations and for two types of functions. It has also been shown that a dithiol function has a greater binding power of metals than a hydroxy-thioketone function
Lambert, Thibault. « Sources, production et transfert du carbone organique dissous dans les bassins versants élémentaires sur socle : apports des isotopes stables du carbone ». Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00857422.
Pernet-Coudrier, Benoit. « Influence de la matière organique dissoute sur la spéciation et la biodisponibilité des métaux : cas de la Seine, un milieu sous forte pression urbaine ». Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00366692.
Djae, Tanalou. « Propriétés de complexation de la matière organique dissoute vis-à-vis du cuivre dans les systèmes sol-plante amendés avec des produits résiduaires organiques ». Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0092.
Understanding copper (Cu) bioavailability determinants in agricultural soils amended with organic waste (OW) is a major ecotoxicological issue in order to preserve soil fertility. Copper speciation in soil solution is conventionally considered in predictive ecotoxicology as the main chemical determinant of Cu bioavailability for soil organisms. Considering the high affinity of Cu for dissolved organic matter (DOM), Cu speciation in soil solution is highly influenced by its complexation with DOM. The speciation models conventionally used in predictive ecotoxicology take into account the variability of DOM concentration but are parameterized by default regarding DOM complexing properties (density and site affinity). However, OW inputs and root activities in the rhizosphere appear able to alter both DOM concentration and its complexing properties. My PhD work proposed (i) to demonstrate the variability in DOM complexing properties in soil-plant systems amended with OW and (ii) to evaluate the impact of this variability on Cu speciation prediction in soil solution.A very wide variability in DOM complexing properties was observed between the 55 soils studied. Plants induced strong changes in DOM complexing properties. The contributions of OW to soil induced an almost systematic increase in DOM complexing properties. Besides considering changes in DOM concentration, pH and total Cu concentration in soil solution, the consideration of variability in DOM complexing properties has substantially improved the Cu speciation prediction in soil solution in comparison with WHAM default setting