Teses / dissertações sobre o tema "Qualité de l'eau – Effets des herbicides"
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Mohamed, Ali Antoissi. "Etude d'un procédé d'oxydation avancée couplé plasma non thermique/carbone activé fonctionnalisé pour le traitement d'herbicides dans l'eau". Electronic Thesis or Diss., Orléans, 2024. http://www.theses.fr/2024ORLE1004.
Texto completo da fonteHerbicides are among the most common and dangerous contaminants found in aquatic environments. These pollutants can have carcinogenic and mutagenic effects on humans. They also pose potential dangers to the environment. It is therefore necessary to develop innovative treatment processes. Among these, Non-Thermal Plasmas (NTP) can be used effectively. NTP are capable to generate oxidizing species (HO°, O3, O°, H2O2, etc.), with high oxidation potentials, which can react with organic molecules in water. However, these treatments are not always sufficient. One of the solutions being studied is to couple plasma with activated carbons (AC). This work presents the study of targeted herbicide treatment (2,4-dichlorophenoxyacetic acid and glyphosate) and the main glyphosate metabolite aminomethylphosphonic acid (AMPA) by non-thermal plasma (NTP) coupled with AC. Initially, the study focused on the treatment of 2,4-D in order to implement the processes on a pollutant that has already been studied with other treatment processes. The obtained results shows a strong synergistic effect of the NTP/AC coupling. The best coupling was obtained by associating NTP with Fe-L27 AC, allowing a complete degradation and a high mineralization of 65% for a 2,4-D solution (with a concentration of 50 ppm) for a treatment time of 120 minutes. During alone NTP treatments, for the same treatment time, the degradation rate was 79% with no mineralization. The various analyses carried out confirmed that the observed degradation and mineralization were actually linked to a catalytic effect of the AC and not due to adsorption. After validating of the synergistic effects of the coupled process, the thesis work continued by studing the NTP/Fe-AC coupling for the treatment of glyphosate and AMPA to assess the process's ability to be generalized to treat other herbicides in natural matrices. Complete degradation was achieved after 120 minutes of treatment for glyphosate and 180 minutes of treatment for AMPA and a complete mineralization of the treated solution after 240 minutes for the treatment of a glyphosate/AMPA mixture (20 ppm/10 ppm)
Perrin-Ganier, Corinne. "Dispersion et transformation de l'isoproturon dans le sol et l'eau". Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL074N.
Texto completo da fonteLn order to identify processes that act on herbicide isoproturon transfer in soil and water, several experimental studies were attempted. Ln the field, isoproturon appeared to reach surface soil water early after treatment. Then, the same soil was used to fill lysimeters placed under natural climatic conditions. Rainwater was able to produce large exportations only during the first month after treatment, because isoproturon, not yet fully degraded, was very mobile. Last, experiments under laboratory controlled conditions showed that isoproturon was sorbed only weakly on soil components. On the opposite, some of its degradation products, which rapidly represent the greatest part of residues, were more strongly held to soil
Loiseau, Liguori Maria. "La qualité des plantes en pots : influence du substrat et du régime d'irrigation". Angers, 1991. http://www.theses.fr/1991ANGE0015.
Texto completo da fonteMalotaux, Christophe. "Les Triazines-atrazine entre autres, présences dans l'environnement et dans l'eau". Paris 5, 1992. http://www.theses.fr/1992PA05P242.
Texto completo da fonteCastañeda, Pinzon Eduardo Alberto. "Contribution de méthodes non destructives à l'évaluation de l'effet de l'eau sur les enrobés bitumineux". Nantes, 2004. http://www.theses.fr/2004NANT2074.
Texto completo da fonteMoisture and stripping (debonding of bitumen and aggregate) are a key element in the distress of bituminous mixtures in the tropical countries. Most of the laboratory testing procedures are destructive and require many specimens. This study aims at understanding the mechanical characteristics evolution for compacted bitumen-aggregate mixtures, using a non-destructive test. The classical study of stiffness evolution highlights the effect of the mineralogical nature of the aggregate skeleton and the bitumen content. The evolution of complex modulus appears to be relevant in evaluating moisture damage, showing the consistent results. It's modelling allows to determine a factor (D) related to moisture-induced damage
Nivelle, Élodie. "Évaluation des effets de l'azote et des herbicides sur les indicateurs qualitatifs du sol dans des agrosystèmes contrastés". Thesis, Amiens, 2017. http://www.theses.fr/2017AMIE0026/document.
Texto completo da fonteNowadays, the use of synthetic nitrogen fertilizers and herbicides is required to ensure cropping systems productivity and meet the demand for food of a growing population. However, the potential effects of these synthetic products on agrosystem’s below- and above-ground properties have been described to be dependent of soil physicochemical and biological characteristics on which they are applied. Especially, it seems that soils under no-till and continuous cover-cropping, characterized by contrasted edaphic properties as compared to soils managed under annual plowing, may change the non-target effects of certain herbicides. Several field experiments, as well as two mesocosm studies, evidenced that cropping systems conducted under no-till with continuous cover-cropping were associated to increased organic carbon and nitrogen contents, microbial functional activities, arbuscular mycorrhizal fungi (AMF) spore density, and maize root colonization by AMF. Secondly, nitrogen fertilization induced negative effects on soil biological indicators such as dehydrogenase activity while it improved plant productivity and nymph survival of certain above-ground pests. Thirdly, glyphosate, a total herbicide, increased degradation time of organic substrates, while it did not change AMF activity when applied alone. However, the combinaison of glyphosate plus nitrogen fertilization in a soil fertilized over a 6-year period led to a decreased root colonization of bean by AMF. Thus, the long term nitrogen fertilization is capable to change the non-target effects of glyphosate. Finally, S-Metolachlor, a selective herbicide, increased nitrate content of soils subjected to no-till, while those conducted under annual plowing revealed no effect, and increased ammonium content of earthworm casts in soils managed under no-till with nitrogen fertilization for 6 years. We conclude that the effects of herbicides on agrosystem's above- and below-ground properties are mainly due to the combination with other agricultural practices such as nitrogen fertilization
Masselot, Gérard. "La synécoparcimonie : un outil d'évaluation biologique de la qualité des eaux courantes : Théorie et applications". Paris, Muséum national d'histoire naturelle, 2005. http://www.theses.fr/2002MNHN0027.
Texto completo da fonteA new freshwater biomonitoring tool, the synecoparsimony method, is proposed and tested. The methodological bases are explained. Its validity is tested on several real cases, of various geographical origins (neartic and west-palearctic). It is shown that this method can be used as well to analyze faunistic data as microfloristic. The new tool makes it possible to minimize the ad hoc hypothesis. It enables direct and rigorous confrontation between biological data and the mesologic characteristics of the rivers. The concept of “bio-indicator” taxa is discussed, and the concept of “significant taxa” is proposed. The new European freshwater biomonitoring tools ara studied and criticized. It is shownthat the new suggested method can allow a relevant approach of the quality of water and/or of aquatic environments. Its validity field is specified, and the complementary studies necessary to improve this new tool are exposed. The need for the use of “total evidence” matrices of qualitative biological data, necessary including “rare” taxa, is shown. The specific level of determination of taxa is confirmed as being the most informative. The method we propose could be integrated as a complementary tool available for freshwater managers in Europe
Shinn, Cândida. "Impact of toxicants on stream fish biological traits". Toulouse 3, 2010. http://thesesups.ups-tlse.fr/1131/.
Texto completo da fonteIn order to guarantee a basis for adequate water quality for humans and the natural environment, the European Union has requested that all member states attain at least good ecological and chemical water quality in all surface waters by 2015, in what is know as the Water Framework Directive. Biologically-based tools are thus needed to adequately assess the ecological status of water bodies. Such tools will aid water managers in assessing, reporting, and eventually protecting such an important resource. The main objective of this thesis work was to evaluate the status of native fish populations in toxicant-impacted rivers in South-West France using a number of fish biological traits. The historically polluted environment of the River Lot has been strongly impacted by heavy metals during and after mining activities took place in certain parts of the river basin. The concentration of copper, zinc, cadmium and lead were quantified in muscle and liver of 3 fish species, as well as in environmental samples (water, sediment, moss) in 1987 and 2007. The situation of the River Lot has improved over the last 2 decades although there is still margin for amelioration according to criterion for the protection of freshwater aquatic life. The average concentrations of cadmium in fish muscle in 2007 were above the maximum safe for human consumption defined by the European Commission. More than half of the Adour-Garonne river catchment area is covered by agricultural land. In this context, the impact of agrochemical pollution on wild gudgeon and chub populations was assessed. A set of biological traits were measured for each species and the link to pesticide toxicity levels tested. Upon removal of confounding effects (genetic variation, geographical distance, water parameters), 4 of the 17 morphological traits studied on the gudgeon were significantly linked to pesticide toxicity. Such differences in body shape are susceptible to take place during early developmental stages, thus indicating that fish were indeed exposed to change-inducing stressors such as toxicants throughout their development. Chub general condition decreased while gonad size increased with increasing toxicity. Histopathological observations of liver tissue indicate that chubs from more polluted sites have reduced lipid storage and increased immunological stress. In order to verify whether pesticides found in the Adour-Garonne river basin cause sub-lethal effects on fish, farm-raised juvenile rainbow trout were exposed in laboratory conditions to low levels of a mixture of herbicides (atrazine, linuron and metolachlor). During the 5-day exposure, trout behaviour was monitored. The increase in number of aggressions of control fish was reflected in an increase of movements per fish, whilst this relationship was not seen in exposed fish. In average, exposed fish tended to occupy lower compartments than control fish. Juvenile trout exposed to a mixture of pesticides thus presented a general hypoactivity, possibly a handicap to survival in the long term. The overall results of these investigations indicate that fish are relevant as environmental bioindicators and as model test organisms to evaluate the effect of sub-lethal levels of contaminant mixtures, in the field and in laboratory conditions. When testing whether there is a significant relationship between contamination and a biological response, it is important to take into account multiple confounding factors, both environmental as well as innate to the organism. In this way, the link between presence/magnitude of contamination and effect on the ecosystem can be clearly established, and used to promote preventive and protective measures for species conservation and the protection of a basic resource - water
Cassan, Delphine. "Santé et qualité de l'environnement de piscines publiques chlorées". Montpellier 1, 2005. http://www.theses.fr/2005MON14001.
Texto completo da fonteAguilar, Ibarra Alonso. "Les peuplements de poissons comme outil pour la gestion de la qualité environnementale du réseau hydrographique de la Garonne". Phd thesis, Toulouse, INPT, 2004. http://oatao.univ-toulouse.fr/7394/1/aguilar.pdf.
Texto completo da fonteBrunet, Claude. "Effets interactifs d'une forte charge en éléments nutritifs et de la vitesse du courant sur la communauté périphytique : études en canaux artificiels". Lyon 1, 2000. http://www.theses.fr/2000LYO10091.
Texto completo da fonteGallien, Manon. "La résilience des Systèmes Alimentaires de qualité différenciée : approche pour la compréhension des dynamiques de protection de la qualité de l'eau en agriculture". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE2067/document.
Texto completo da fonteIn 2009, The Grenelle de l'Environnement (French environmental pact) introduced environmental clauses within Geographical Indications (GI) specifications. French Water agencies (agences de l’eau) perceive it as a good opportunity to address the issue of agricultural pollution, by takings actions at the upstream level. In this context, this study examines how certainfood quality processes are proactively setting targets for conserving water. This question led to develop a global approach in order to look at the issues of water quality from the wider angle of environmental preservation. It requires not only to focus on regulation tools of food quality products but also to take into account a larger set of environmental actions. Along the same lines, the theoretical framework of the resilience of food system of differentiated quality has also been developed. It allows to study proactive environmental dynamics set up by stakeholders to deal with perturbations linked to natural resources degradation, such as water. Those perturbations can be factual (measured) or represented, when stakeholders consider a potential risk. This analytical framework has been applied on case studies in viticulture and fruit production in the South-East of France. The results underscore the complexity of environmental dynamics: they are based on a set of complementary actions and require the mobilization of key players, able to engage in a collective dynamics but also to have a wider vision of food systems, both by looking at the vertical dimension (market oriented) and horizontal dimension (link with the local territory)
Tejerina, Garro Francisco Leonardo. "Etude des relations habitat-poissons dans les eaux courantes de Guyane française pour l'évaluation de la qualité du milieu aquatique". Montpellier 2, 2001. http://www.theses.fr/2001MON20164.
Texto completo da fonteTrouilhé, Marie-Cécile. "Etude biotique et abiotique de l'habitat préférentiel de l'écrevisse à pattes blanches (Austropotamobius pallipes) dans l'ouest de la France : implications pour sa gestion et sa conservation". Poitiers, 2006. http://www.theses.fr/2006POIT2289.
Texto completo da fonteFrom November 2002 to December 2005, the preferential habitat of the indigenous white-clawed crayfish (Austropotamobius pallipes) was determined in the “Pays de Gâtine” (Deux-Sèvres, France). For this study, eight brooks, from four different catchments, were selected. Two sampling sites were monitored per brook; the first being where the population was present and the second 2 to 3 km downstream of the population. Twenty-three physico-chemical parameters, concerning both mineral and organic water components, were regularly measured as well as four samplings of benthic macroinvertebrate fauna. This study made it possible to build up a large data base characterizing the tolerance levels of A. Pallipes with respect to certain parameters, which led us to discuss its status as a bioindicator of water quality. The use of multivariate analysis (mainly Principal Component Analysis) showed (i) that organic matter seems to discriminate A. Pallipes presence/absence and (ii) that A. Pallipes presence is closely associated with the occurrence of some families of macroinvertebrates which are very sensitive to organic pollution. PCA also permitted us to considerably reduce the number of abiotic and biotic parameters considered. In addition, the use of these selected parameters to model A. Pallipes presence/absence with Artificial Neural Networks (ANN) showed interesting and promising results for the management and the conservation of this threatened species
Lefebvre, Annick. "Enjeux de la qualité microbiologique de l'eau à l'hôpital : impact sur les colonisations et infections nosocomiales à pseudomonas aeruginosa". Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOMU01/document.
Texto completo da fonteScientific literature allows suspecting but does not clearly indicate a link between water network contamination and Pseudomonas aeruginosa healthcare-associated infections. Guidelines for water samples vary across countries.Our work is based on water samples and P. aeruginosa patients’ samples (healthcare-associated colonizations or infections) in Dijon University hospital between 2005 and 2013.Water outlets contaminations were frequent (17%, CI95% 15.5-18.2). Mixed models on units that moved from a building to another did not show a lower incidence of P. aeruginosa cases in the new building than in the others, although it was less contaminated. Kulldorff’s method allowed detecting few temporal clusters of cases. GEE (Generalized Estimated Equations) models showed a positive association between the proportions of positive water samples in the building in the quarter and the incidence of healthcare-associated cases. This association was still observed in subgroup analyses of intensive care units but was no more observed in the database excluding hematology and intensive care units. Few arguments for an association between water network contamination and P. aeruginosa healthcare-associated colonizations or infections are provided, except in hematology and intensive care units. Given the costs associated with the samples and correctives measures, it could be proposed to limit the samples to these units at risk. Prospective studies with molecular typing methods should be conducted in order to better understand the association between hospital water network microbiologic quality and healthcare-associated infections
Chevalier, Julie. "Utilisation du comportement natatoire de Daphnia magna comme indicateur sensible et précoce de toxicité pour l'évaluation de la qualité de l'eau". Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0443/document.
Texto completo da fonteSwimming behavior is increasingly reported as a sensitive and early indicator of toxicant stress in aquatic organisms. However, it remains unclear how to quantify the sensitivity of swimming behavioral endpoints and how to compare these effect thresholds with standard ecotoxicological endpoints used in risk assessment. To date, the systematic assessment of the sensitivity of swimming behavioral endpoints in daphnia is limited because of the restrained test capacity of existing behavioral analysis systems. Hence, we developed a new behavioral analysis multi-cellsystemnamed “Multi-DaphTrack” with a high throughput testing capacity in order to enhance our understanding of swimming behavioral effects in Daphnia magnaunder chemical exposure. Twelve compounds covering different modes oftoxic action were selected and tested in this new system andin a single-cell commercialized biomonitor (DaphToxI®) and with the acute standard test.Our new multi-cellexposure system detectedsignificant and early swimming behavioral effects (i.e.,increase of the average speed) for most of the tested compounds and this, from the first hour of exposure at concentrations near the EC10(48h). Contrastedbehavioral profiles were observed for average speed (i.e., intensity, time of effect onset, effect duration), but no distinct behavioral profiles could be drawn from the chemical mode of action. Despite less sensitive,the DaphToxI®gave similar trends (i.e.,rapid peak increase) compared to our “Multi-DaphTrack” system. To conclude, behavior analysis using our “Multi-DaphTrack”systemcould be used as an alternative or complement to the current acute standard test for toxicity assessment of chemicals. With some additional improvements and validations, it also could be used forquality assessment of waterbodiesand sewages
Imbert, Alexis. "Pêche récréative et fonctionnement des lacs : conséquences des pratiques d'amorçage et aide à la gestion opérationnelle". Electronic Thesis or Diss., Toulouse 3, 2023. http://www.theses.fr/2023TOU30239.
Texto completo da fonteTerrestrial subsidies to aquatic ecosystem have a strong impact on their functioning. In addition to natural subsidies, human activities also generates allochthonous inputs. Recreational fishing, through groundbaiting practices, which consists in introducing organic matter to optimise fish harvest, generates human subsidies which properties and impact on aquatic ecosystem are poorly known, despite their potential implication on lake eutrophication. This study aimed to determine the composition and properties of angling bait subsidies in order to quantify their consumption by fish, to assess impacts on water quality and to propose groundbaiting management measures. In the first chapter, the analyses of stoichiometric composition of four angling bait types revealed a high level of nitrogen and phosphorus, variable according type, which phosphorus contents up to 17 times higher than those observed in natural subsidies (tree litter). In the second chapter, the microplastic concentration was quantified. Two of the three angling bait types analysed contained microplastics, with an average concentration of 17.4 particles.kg-1. Through the analysis of stable isotope values, the third chapter highlighted a contrasted angling bait consumption by cyprinid fishes in gravel pit lakes supporting different fishery types. Some individuals used angling baits as their major energy source, accounting for up to 80.5 % of the resources consumed. In the fourth chapter, a field survey coupled with a questionnaire to anglers allowed to assess a strong seasonality in the angling bait quantities used according to fishing technique practiced. Specialised carp anglers used in average 4.6 kg of angling baits per day. Associated to a strong summer input, these introduced quantities generated an important eutrophication, modelled with a numerical lake model functioning. This model also identified the limitation of individual amount of baits as the most efficient groundbaiting management measure, which allowed to drastically reduce the total phosphorus and chlorophyll-a concentrations. This work allowed to identify angling bait as a subsidy with qualitative, quantitative and temporal properties highly variables which modulate the impact on ecosystems. In some cases, angling bait subsidies lead to a substantial water quality degradation, which justifies the need to set up some groundbaiting
Kengne, Fotsing Joséphine. "Bio-évaluation des cours d’eau de la région Ouest du Cameroun à l’aide des macroinvertébrés benthiques et construction d’un indice multimétrique régional". Thesis, Lille 1, 2018. http://www.theses.fr/2018LIL1R067/document.
Texto completo da fonteBenthic macroinvertebrates have always been recognized as better tools for bio-assessment of the ecological quality of streams in both tropical and temperate areas. The main objective of this work was to evaluate the water quality of the Western region of Cameroon most degraded by various and multiple anthropogenic activities. From these communities of macroinvertebrates benthic and their ecological preferences at the mesohabitat scale, we resulted to the construction of a bio-assessment index of the ecological quality of streams adapted to this region. From multivariate analyzes, a stream biotypology into the sampled sites, allowed us to identify different distribution patterns, with on the one hand reference sites or non-impacted and the other hand, impacted sites based on the level of urbanization and the nature of the effluents in the different sub-watersheds. A multimetric index of biological quality (MMIWC), measuring the deviation from the reference, could be created, thanks to these two groups of stations. Among the 18 candidate metrics (transformed into Ecological Quality Ratio), we selected metrics with high discrimination efficiency and a low coefficient of variation in the reference conditions. The best performing index include two metrics derived to the taxonomic diversity (Shannon index) and taxonomic composition (1-GOLD). From a test dataset different to learning dataset, we were able to verify that MMIWC was stable in the reference conditions and sensitive to the full range of anthropogenic pressures present in this region, thus confirming its generalist character
Bringer, Arno. "Environnement & Conchyliculture : étude des effets des microplastiques et pesticides chez l’huître creuse, Crassostrea gigas, des Pertuis Charentais". Electronic Thesis or Diss., La Rochelle, 2021. http://www.theses.fr/2021LAROS012.
Texto completo da fonteMicroplastics (MPs) are widely distributed in coastal areas and oceans around the world. MPs are of environmental concern due to their potential impacts on a wide range of marine organisms, so assessing their impact on ecosystems has become an urgent research priority. In addition, the phytosanitary substances regularly used in agriculture flow into coastal environments by runoff. This thesis focused on (i) an exploratory study of a pilot site in Pertuis Charentais (PC) in order to assess the extent of plastic contamination in order to be able to perform toxicity tests on (ii) the early and (iii) late stages of development in the Pacific oyster, Crassostrea gigas. This work provides a first investigation of the plastic contamination state (macro and micro) of a coastline PC pilot study site, where the presence of aquaculture plastics as well as significant concentrations of MPs in beach sediments, have been identified. In addition, the experiments carried out under controlled laboratory conditions, inform us about the toxic effects of PE-MPs and pesticides on the early stages of development (embryotoxicity). Pesticides dosed in PC seawater have shown significant effects at concentrations close to the natural environment, while MPs are toxic at higher concentrations. Effects on development, growth, and swimming behaviour are to be noted. Additional experiments were carried out on later stages in particular oyster spat showed altered valve behaviour following a 25-day exposure to PE-MPs and chlortoluron, under laboratory conditions. Intergenerational effects have been observed with the use of environmental MPs (cocktail of PE, PP and PVC), aged near oyster farms. The quality and success of fertilization was modified as well as the development and behaviour of D-larvae from parents exposed for two months. These initial results will help strengthen the knowledge of the scientific community and inform shellfish industry professionals and stakeholders on the risks of emerging contaminants, such as MPs and pesticides. Adaptations of shellfish farming practices will be necessary in order to avoid a probable deterioration in the quality of coastal waters in the PC
Morin, Soizic. "Bioindication des effets des pollutions métalliques sur les communautés de diatomées benthiques : approches in situ et expérimentales". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2006. http://tel.archives-ouvertes.fr/tel-00164971.
Texto completo da fonteBillat, Valérie. "Etude de l'influence de l'état de surface sur la qualité de la mesure de la couleur de l'océan à l'aide d'un simulateur de mission spatiale". Phd thesis, Université Paris-Diderot - Paris VII, 1997. http://tel.archives-ouvertes.fr/tel-00955254.
Texto completo da fontePougnet, Frédérique. "Etat de la qualité des eaux de l’estuaire de la Gironde : cas du cadmium et des butylétains". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0011/document.
Texto completo da fonteThe Gironde Estuary is affected by historical multi-metal pollution. Persistent contamination by cadmium (Cd) prevents complete recovery of the Gironde oyster farming, and implies potential risks for the most important oyster farming areas in France (Marennes-Oléron). In addition, the water quality survey governed by the Water Framework Directive (WFD), has downgraded the "Central Gironde" water body in 2009 due to the presence of TBT, a highly toxic organo-metallic compound, on the list of priority substances and banned for several decades.This work relies on 12 oceanographic campaigns, including a monthly survey at the WFD monitoring sites (KP52 and KP86) in 2015 with additional sampling at KP30. Furthermore, 3 longitudinal profiles were carried out along the salinity gradient to characterize the current state of water quality in the Gironde Estuary for Cd and butyltin species, in a perspective of decontamination and resilience. The results showed the lowest dissolved Cd additions (Cdd) along the salinity gradient since 2002, for contrasting hydrological conditions. The development of several calculation methods has shown a decrease in net Cdd flows over the past 30 years by a factor of ~10. Particulate Cd (Cdp) concentrations were in the range of 0.45 ± 0.07 mg/kg during the past 10 years. This value is higher than the geochemical background of the saline Gironde Estuary (0.2 mg/kg) suggesting the persistence of potential contamination of the coastal zone by desorption. Physical and chemical measurements at the estuary mouth coupling ADCP with geochemical analyses have provided estimates of the suspended particulate matter (SPM) and Cdp fluxes, for extreme hydrological conditions. The set of previous scientific results (measurements and hydro-sedimentary modeling), the analysis of time-series of flood events and tidal coefficients since 1990, have been integrated into a conceptual model for the export of SPM and Cdp to the coastal zone. The 2015 monthly survey according to the WFD has produced two distinct values and annual average concentrations both exceeding the respective environmental quality thresholds showing that the Gironde Estuary remains downgraded with respect to TBT. Longitudinal records of butyltins (TBT, dibutyltin (DBT) and monobutyltin (MBT)) in water, SPM and sediment of the entire Gironde Estuary have pointed to several potential sources including urban discharges (from Bordeaux), industrial releases (Bec d’Ambès) and estuarine dredging activities (from downstream harbours)
Nuttens, Andréïna. "Étude des effets de l'interaction entre polluants et ressources sur Myriophyllum spicatum grâce à une approche couplant écotoxicologie et écologie chimique". Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0143/document.
Texto completo da fonteSimultaneous contamination of aquatic ecosystems by pollutants and nutrients is a major problem whose effects on macrophytes are still unknown. The objective of this thesis was to study the effects of different pollutants, herbicides and trace metal elements (TME), in combination with varying resource availability (nitrogen, phosphorus, or carbon) on Myriophyllum spicatum, using parameters from chemical ecology and ecotoxicology. Tests showed contrasting effects of herbicides, but no effects of the TME. In all cases, resource modifications (nitrate, N:P ratio or sucrose) induced significant effects on the physiology and stoichiometry of the plant, which might alter its response to additional stress like pollutants. These results suggest that an imbalance of resources in the presence of pollutants may lead to unforeseen changes in the combined effects on macrophytes, and also highlight the need to add more informative parameters in tests to meet the challenges of multiple stress and improve environmental risk assessment
Richert, Caroline. "Comparaison de marqueurs biochimiques chez les poissons (induction de l'activité éthoxyrésorufine-O-deéthylase et inhibition de l'activité acétylcholinestérase) et d'indicateurs écologiques (peuplement de macroinvertébrés) pour le diagnostic in situ de la pollution toxique dans les cours d'eau". Lyon 1, 1994. http://www.theses.fr/1994LYO10356.
Texto completo da fonteYouego, Sihon Joëlle Reine. "Impacts des facteurs lithologiques et anthropiques sur la qualité des eaux en zone tropicale urbanisée : cas du bassin versant de la Mefou (Cameroun, Afrique centrale)". Thesis, Toulouse 3, 2019. http://thesesups.ups-tlse.fr/5127/.
Texto completo da fonteThis research addresses the influence of human activities on tropical hydro-ecosystems. Its purpose is to assess the impact of urbanization on water resources. It aims to improve our knowledge of geochemical processes and material transfers in urban and peri-urban areas. The study was conducted in the Mefou river basin (840 km2, Central Africa), a tributary of the Nyong River. This basin includes the entire urban and peri-urban area of the city of Yaoundé, the capital of Cameroon, with a population of about 2.8 million inhabitants, and classified as the country's second largest metropolis. Concentrations of major and trace elements in the dissolved fraction, dissolved and particulate organic carbon, and metals in suspended solids were measured in groundwater and runoff water from the Mefou basin heads to the Nyong River. The results present the interactions between water/rock/soil and the effects of urbanization. The normalization of concentrations with the Upper Continental Crust (UCC) shows the influence of the granito-gneissic bedrock on the composition of groundwater and surface water in the Mefou catchment area. There is an enrichment in alkalis (Na, K), alkaline earths (Ca, Mg), transition metals (Mn, Co, Ni, Cu, Zn, Cd, Pb) and REEs (La, Ce, Nd, Sm, Eu, Gd, Tb, Yb, Lu). The remarkable enrichment of surface waters in Eu is explained by the alteration of plagioclases. Comparison of the Mefou catchment area with the reference sites, the Nsimi catchment area (source and stream of the Mengong) and the Nyong River monitored for more than twenty years under the SNO MTROPICS, shows a very significant enrichment of the waters in major elements (Cl, SO4, NO3, Na, K, Ca, Mg). Human activities lead to water contamination by nutrients and metals, and influence the dynamics of processes such as the absence of metal complexation by organic matter, probably due to the absence or low concentration of humic and fulvic acids. In groundwater, Mn, Al, Ba, Zn, Zn, Fe are the dominant transition metals and nitrate contamination (942 ± 127 µmol/L) is noted with concentrations above the standard set by the World Health Organization (806 µmol/L), and to a lesser extent by some metals like Al, Mn. In surface waters, Fe, Mn, Ba, Al, Zn, Cu are the most important metallic trace elements. However, the average concentration of Mn (4.1 ± 0.8 µmol/L) and the maximum concentration of Fe (267 µmol/L) are higher than the recommended standards (1.8 µmol/L and 35.8 µmol/L, respectively). Pollution is gradually decreasing from Mfoundi (a tributary of the Mefou River in town) to the Mefou River and the Nyong River. This natural self-regulation process is due to the dilution, sedimentation, degradation and adsorption of elements in lowland areas and in the riverbed occupied by macrophytes with a phytoremediator role. Indeed, the large volumes of water from the other tributaries of the Mefou and Nyong rivers, which drain areas with little or no anthropisation, dilute the concentration of elements in the highly mineralised waters from the urban area. The flat relief downstream of the Mefou basin slows the flow of the river and favours the deposition of suspended particles loaded with pollutants. The roots of the macrophytes in this vast and highly developed swampy area trap the organic and mineral pollutants of the Mefou River and contribute to the decrease in their concentration in the river's water
Cakir, Roxelane. "Les fonctions écologiques de régulation des nitrates au sein des bassins versants : des cours d'eau aux territoires". Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30115.
Texto completo da fonteMaintaining good surface water quality within watersheds is a crucial challenge for the society and the proper functioning of aquatic ecosystems. This maintaining is allowed by the water quality regulation service, which is still understudied. A better understanding of this service will help determining the human stressors and the potential protected areas designation. Consequently, this understanding will design an optimal management of the resource. If we take the case of nitrates in watercourses as an indicator of water quality, they are still currently brought in significant quantities from agricultural activities, urban and industrial effluents. The regulation service is provided by ecosystems through natural processes of production, storage and removal. Regulation takes place in both terrestrial and aquatic environments and depends on control factors such as land use and occupation, hydrology, pedology and landscape structure. The use of modelling coupled with observation is thus essential to characterize and quantify the nitrate regulation functions at different organization scales and was the subject of this work. The objectives of this thesis are: (1) quantifying and understanding the spatial and temporal evolution of the ecological functions related to nitrate regulation within the hydrographic network and its watershed area; (2) analyzing the influencing factors on these functions; (3) quantifying the ecological functions with "simple" relationships in order to avoid "complex" modelling; (4) quantifying these ecological functions on the scale of Southwestern Europe in a context of land management and global change. Two scales of spatial organization were addressed: the scale of the water body in the sense of the Water Framework Directive and the scale of the operating system. The methodology was first developed on the Garonne River (50,000 km2) and then applied on the scale of the whole Southwestern Europe (773,000 km2). In this work, we used data from the water agencies throughout Europe, but also scientific data from European projects and specific studies. The results simulated from the SWAT model show that, in the Garonne watershed, nitrate production is on average equal to +1.62 gN.m-2.d-1 and nitrate removal is on average equal to - 1.77 gN.m-2.d-1 within the rivers over the period 2000-2010. These calculations were obtained from modelling on a monthly scale integrating anthropogenic pressures (cities, agriculture, dams). Nitrate removal is more significant during spring and summer in small rivers of alluvial plains, while production is more substantial downstream of large rivers. In the lands, nitrate production in soils is dominant in floodplains, while the in-land removal function is dominant in floodplain forests and wetland areas with high organic matter composition (>2%). These in-stream and in-land ecological functions are landscape-dependent. By comparing with natural maps, the in-land ecological functions have suffered a 76% loss due to strong human stressors in the Garonne watershed. The spatiotemporal dynamics of these in-stream and in-land ecological functions are controlled by the slope, the streamflow, the hydraulic conditions and the nitrate concentration in the surface waters. Based on these control factors, parametric equations modeling in-stream nitrate removal have been developed and validated on the Garonne watershed. The in-stream and in-land ecological functions estimated on a large scale, the scale of Southwestern Europe, have spatial and temporal variations similar to those found in the Garonne watershed and depend on landscape features and anthropogenic influence. Finally, the results of this thesis had been valorized thanks to many collaborations in the hydrological, ecological and economical fields and had been the subject of knowledge transfer to society
Krayem, Maha. "Etude des effets de l'arsenic et du cuivre sur un macrophyte aquatique, Myriophyllum alterniflorum D.C. : évaluation des biomarqueurs pour la détection précoce de pollution". Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0131.
Texto completo da fonteAlternate watermilfoil, Myriophyllum alterniflorum is an aquatic macrophyte presented in the rivers of the Limousin region in France whose potential for bioindication of metal pollution has been demonstrated. The objective of this study is to identify in this species sensitive biomarkers for the early detection of pollution in a river by a metal copper, and a metalloid, arsenic. To achieve this goal, a synthetic medium whose composition is representative of the water quality of the river Vienne, was prepared (Vienne medium). The composition of the medium studied is verified by ICP-MS and ion chromatography (IC). The development of the macrophyte was followed in a control medium, a copper contaminated medium and another contaminated with arsenic at a concentration of 100 µg/L for 21 days. During this period, the respiratory and photosynthetic activities of Myriophyllum alterniflorum, the concentrations of chlorophyll a, b and carotenoids, levels of malondialdehyde, osmotic potential, and phytochelatins were recorded. This monitoring has been made in a closed system (400mL culture boxes) taking into account the trophy of the medium (eutrophic and oligotrophic conditions), and then in a recirculating system (aquariums of 150 L) taking into account the hydrodynamic conditions (turbulent, laminar and quiet areas)
Kazour, Maria. "Active and passive biomonitoring tools for microplastics assessment in two highly polluted aquatic environments : case study of the Seine estuary and the Lebanese coast SOURCES OF MICROPLASTICS POLLUTION IN THE MARINE ENVIRONMENT: IMPORTANCE OF WASTEWATER TREATMENT PLANT AND COASTAL LANDFILL MICROPLASTICS POLLUTION ALONG THE LEBANESE COAST (EASTERN MEDITERRANEAN BASIN): OCCURRENCE IN SURFACE WATER, SEDIMENTS AND BIOTA SAMPLES JUVENILE FISH CAGING AS A TOOL FOR ASSESSING MICROPLASTICS CONTAMINATION IN ESTUARINE FISH NURSERY GROUNDS IS BLUE MUSSEL CAGING AN EFFICIENT METHOD FOR MONITORING ENVIRONMENTAL MICROPLASTICS POLLUTION?" Thesis, Littoral, 2019. http://www.theses.fr/2019DUNK0544.
Texto completo da fontePlastic fabrication is increasing worldwide in response to daily human demands. This mass production is linked to the immense plastic marine litter found all around the world: each synthetic material is meant to find its way back into the aquatic systems. Anthropogenic pressure and the immense human population, the lack of appropriate plastic treatment process and the growing industrial activities advocate their presence in the aquatic environments. These plastics are then found in the form of microplastics (microscopic particle with a size < 5 mm) observed in the water, in the sediments and are prone to be ingested by various marine organisms along the trophic chain. This thesis focuses on (1) assessing microplastics sources and input into the aquatic environment and their occurrence in biota, and (2) to test the feasibility of using transplanted organisms (caging) for monitoring microplastics pollution in the marine coastal environment. Two coastal areas highly impacted by anthropogenic pressures were studied: Le Havre in France and the Lebanese coast. For the former, the role of a municipal wastewater treatment plant (WWTP) effluent and an abandoned coastal landfill as pathways for microplastics (MPs) input into the marine environment was assessed. MPs were first analyzed in raw sewage influent, sludge and effluent samples, and their fate was studied along a distance gradient from the WWTP in three matrices: surface water, sediments and wild mussels (Mytilus spp). MPs were found in all matrices with a decreasing abundance from the effluent. Strong MPs abundances (higher than those found near the WWTP effluent) were observed in the vicinity of the coastal landfill suggesting its importance as a MPs entry route into the marine coastal environment. Whereas for the Lebanese coast, we evaluated for the first time the MPs pollution in the seawater, sediments and two important seafood species (one pelagic fish: Engraulis encrasicolus and one bivalve: Spondylus spinosus). Results showed different patterns of MPs concentration in the analyzed matrices. The occurrence of MPs in the biota was high (83.4% and 86.3% in anchovies and spiny oysters, respectively). These results highlighted the high MPs pollution found in the Levantine Basin in comparison to other Western Mediterranean regions. In addition, the obtained results indicate the potential contribution of coastal landfills to this pollution. Most often microplastics studies involve collection of organisms’ samples from natural populations. In this thesis, we tested the feasibility of using transplanted organisms (caging) for monitoring microplastics’ pollution in the marine coastal environment. We developed caging experiments with juvenile European Flounder, Platichthys flesus, in estuarine nursery grounds and blue mussels, Mytilus edulis, in coastal marine environment. For each species, the abundance and characteristics (shape, size, color and type of polymers) of MPs ingested by caged individuals are compared with those ingested by wild individuals collected at the same site and with those found in their surrounding environment (surface water and sediments). Our results suggest that transplanted organisms (caging) may be a promising tool for MPs biomonitoring making monitoring more reliable with an accurate assessment of the biological effects of MPs over a predetermined exposure period
Lanoux, Aurélie. "Caractérisation et rôle respectif des apports organiques amont et locaux sur l'oxygénation des eaux de la Garonne estuarienne". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00874532.
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