Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O picoplâncton (0,2 - 2,0 m) e ultraplâncton (> 2,0 - 5,0 m) despertam interesse por utilizarem ativamente a matéria orgânica dissolvida, estabelecendo a alça microbiana. Responsáveis por 50-80% da produção primária em águas oligotróficas, essas frações apresentam elevadas eficiência luminosa e razão superfície/volume que as permitem alcançar alto desenvolvimento mesmo sob baixas luminosidade e disponibilidade de nutrientes. Buscando relacionar a distribuição espacial e composição da comunidade pico e ultraplanctônica aos controles bottom-up na plataforma continental e talude ao largo dos Estados do Rio de Janeiro e São Paulo (22S a 26S), foram coletadas amostras de água em 39 estações oceanográficas e utilizadas as imagens dos sensores MODIS Terra e Aqua, bem como dados de hidrografia, para a descrição dos fenômenos oceanográficos de mesoescala. A abundância total de ambas as frações de tamanho, assim como a dominância do picoplâncton, reduziu em função do distanciamento da costa. Os organismos autotróficos foram em média (102 cél.mL-1 a 104 cél.mL-1 ) majoritariamente uma ordem de grandeza inferiores aos heterotróficos (103 cél.mL-1 a 105 cél.mL-1). A Água Central do Atlântico Sul (ACAS) e as plumas das baías de Guanabara e Sepetiba (RJ) permaneceram na plataforma interna favorecendo o aumento na concentração dos macronutrientes e refletindo na mudança da estrutura da comunidade através do aumento da contribuição de autótrofos no centro da plataforma, principalmente do ultraplâncton à superfície (cerca de 21%) e na profundidade do máximo de clorofila (44%). O transporte de águas costeiras carreadas por uma corrente de origem sul gerou o vórtice de plataforma identificado nas imagens de satélite para a região da plataforma interna de Ubatuba (SP), onde concentrações mais elevadas de amônio (0,28 M) e fosfato (9,64 M) a partir dos 50 m sustentaram maior densidade do ultra autótrofo (2,89 x 103 cél.mL-1) que superou a densidade de heterótrofos (2,50 x 103 cél.mL-1) no máximo de clorofila. Os resultados destacaram um forte gradiente nerítico-oceânico na distribuição dos organismos. Sugerem ainda a predominância do metabolismo heterotrófico na maior parte das águas oligotróficas da plataforma e talude entre o Rio de Janeiro e São Paulo, bem como a presença de caráter autotrófico naquelas regiões influenciadas por feições de mesoescala, como plumas estuarinas e vórtices de plataforma. / The picoplankton (0.2 2.0 m) and ultraplankton (>2.0 5.0 m) arouse interest because they actively use the dissolved organic matter and establishe the microbial loop. Responsible for 50-80% of primary production in oligotrophic waters, these fractions have high luminous efficiency and high surface/volume ratio that enable them to achieve high development even under low light and low nutrient availability. Seeking to relate the spatial distribution and composition of pico and ultraplanktonic community to the bottom-up control and mesoscale oceanographic features in the Brazilian continental shelf and slope off Rio de Janeiro and São Paulo (22S to 26S), water samples were taken in 39 oceanographic stations and images of MODIS Terra and Aqua sensors, toghether with hidrography, were employed to decribe the mesoscale oceanographic features.The total abundance of both size fractions, as well as the dominance of picoplankton, decreased as a function of distance from the coast. Autotrophic organisms were, predominantly, on average (102 cell.mL-1 to 104 cell.mL-1) one order of magnitude lower than the heterotrophic (103 cell.mL-1 to 105 cell.mL-1). The South Atlantic Central Water (SACW) and the plumes of Guanabara and Sepetiba bays (RJ) remained in the inner shelf favoring an increase in macronutrients concentration and reflecting changes in community structure by the increase of autotrophs contribution, especially in the central portion of the shelf, mainly ultraplankton at surface (21%) and in maximum chlorophyll depth (44%). The transport of coastal waters carried by a current from south caused the shelf eddy identified by water colour/chlorophyll images for the region of Ubatuba inner shelf (SP), where high concentrations of ammonium (0,28 M) and phosphate (9,64 M) near the depth of 50 m supported higher density of autotrophic ultraplankton (2.89 x 103 cells.mL-1) which exceeded the density of heterotrophs at the chlorophyll maximum (2.19 x 103 cells.mL-1). Our results highlighted a strong neritic-oceanic gradient in the distribution of these organisms. They also suggest the predominance of the heterotrophic metabolism in the majority of the oligotrophic waters of the shelf and slope between Rio de Janeiro and São Paulo, as well as the presence of an autotrophic nature in those regions influenced by mesoscale features, such as estuarine plumes and shelf eddies.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O picoplâncton (0,2 - 2,0 m) e ultraplâncton (> 2,0 - 5,0 m) despertam interesse por utilizarem ativamente a matéria orgânica dissolvida, estabelecendo a alça microbiana. Responsáveis por 50-80% da produção primária em águas oligotróficas, essas frações apresentam elevadas eficiência luminosa e razão superfície/volume que as permitem alcançar alto desenvolvimento mesmo sob baixas luminosidade e disponibilidade de nutrientes. Buscando relacionar a distribuição espacial e composição da comunidade pico e ultraplanctônica aos controles bottom-up na plataforma continental e talude ao largo dos Estados do Rio de Janeiro e São Paulo (22S a 26S), foram coletadas amostras de água em 39 estações oceanográficas e utilizadas as imagens dos sensores MODIS Terra e Aqua, bem como dados de hidrografia, para a descrição dos fenômenos oceanográficos de mesoescala. A abundância total de ambas as frações de tamanho, assim como a dominância do picoplâncton, reduziu em função do distanciamento da costa. Os organismos autotróficos foram em média (102 cél.mL-1 a 104 cél.mL-1 ) majoritariamente uma ordem de grandeza inferiores aos heterotróficos (103 cél.mL-1 a 105 cél.mL-1). A Água Central do Atlântico Sul (ACAS) e as plumas das baías de Guanabara e Sepetiba (RJ) permaneceram na plataforma interna favorecendo o aumento na concentração dos macronutrientes e refletindo na mudança da estrutura da comunidade através do aumento da contribuição de autótrofos no centro da plataforma, principalmente do ultraplâncton à superfície (cerca de 21%) e na profundidade do máximo de clorofila (44%). O transporte de águas costeiras carreadas por uma corrente de origem sul gerou o vórtice de plataforma identificado nas imagens de satélite para a região da plataforma interna de Ubatuba (SP), onde concentrações mais elevadas de amônio (0,28 M) e fosfato (9,64 M) a partir dos 50 m sustentaram maior densidade do ultra autótrofo (2,89 x 103 cél.mL-1) que superou a densidade de heterótrofos (2,50 x 103 cél.mL-1) no máximo de clorofila. Os resultados destacaram um forte gradiente nerítico-oceânico na distribuição dos organismos. Sugerem ainda a predominância do metabolismo heterotrófico na maior parte das águas oligotróficas da plataforma e talude entre o Rio de Janeiro e São Paulo, bem como a presença de caráter autotrófico naquelas regiões influenciadas por feições de mesoescala, como plumas estuarinas e vórtices de plataforma. / The picoplankton (0.2 2.0 m) and ultraplankton (>2.0 5.0 m) arouse interest because they actively use the dissolved organic matter and establishe the microbial loop. Responsible for 50-80% of primary production in oligotrophic waters, these fractions have high luminous efficiency and high surface/volume ratio that enable them to achieve high development even under low light and low nutrient availability. Seeking to relate the spatial distribution and composition of pico and ultraplanktonic community to the bottom-up control and mesoscale oceanographic features in the Brazilian continental shelf and slope off Rio de Janeiro and São Paulo (22S to 26S), water samples were taken in 39 oceanographic stations and images of MODIS Terra and Aqua sensors, toghether with hidrography, were employed to decribe the mesoscale oceanographic features.The total abundance of both size fractions, as well as the dominance of picoplankton, decreased as a function of distance from the coast. Autotrophic organisms were, predominantly, on average (102 cell.mL-1 to 104 cell.mL-1) one order of magnitude lower than the heterotrophic (103 cell.mL-1 to 105 cell.mL-1). The South Atlantic Central Water (SACW) and the plumes of Guanabara and Sepetiba bays (RJ) remained in the inner shelf favoring an increase in macronutrients concentration and reflecting changes in community structure by the increase of autotrophs contribution, especially in the central portion of the shelf, mainly ultraplankton at surface (21%) and in maximum chlorophyll depth (44%). The transport of coastal waters carried by a current from south caused the shelf eddy identified by water colour/chlorophyll images for the region of Ubatuba inner shelf (SP), where high concentrations of ammonium (0,28 M) and phosphate (9,64 M) near the depth of 50 m supported higher density of autotrophic ultraplankton (2.89 x 103 cells.mL-1) which exceeded the density of heterotrophs at the chlorophyll maximum (2.19 x 103 cells.mL-1). Our results highlighted a strong neritic-oceanic gradient in the distribution of these organisms. They also suggest the predominance of the heterotrophic metabolism in the majority of the oligotrophic waters of the shelf and slope between Rio de Janeiro and São Paulo, as well as the presence of an autotrophic nature in those regions influenced by mesoscale features, such as estuarine plumes and shelf eddies.

Il s’agit de l’étude des successions écologiques du phytoplancton dans la lagune de Ghar El Melh au niveau de 5 stations pendant (i) un suivi bimensuel allant du janvier 2011 à janvier 2012 et (ii) un suivi saisonnier à partir du novembre 2012 à mars 2013. L’étude écologique a été consacrée au microphytoplancton en relation avec les facteurs abiotiques (température, salinité et nutriments) et biotiques (microalgues épiphytes, kystes des dinoflagellés, ultraplancton et ciliés). L’analyse hydrologique du milieu a montré une variation principalement saisonnière de la plupart des paramètres avec des valeurs élevées de la température et de la salinité en été et des concentrations exceptionnelles des nutriments en automne et en hiver. Le phytoplancton de la lagune de Ghar El Melh a été principalement dominé par les dinoflagellés et les diatomées avec une manifestation alarmante des espèces nuisibles atteignant plus que 70 % du peuplement. Ces proliférations ont été remarquées durant toute l’année avec une manifestation plus marquante dans les régions internes de la lagune ce qui est principalement tributaire à la température de l’eau, l’azote total, le nitrogène et l’orthophosphate. Une importante contribution des espèces épiphytes au phytoplancton a été signalée notamment celle du dinoflagellé toxique Prorocentrum lima. L’inventaire spécifique du phytoplancton dominé par l’espèce Prorocentrum micans (> 28 %) et d’autres espèces ne produisant pas de kyste a été en concordance avec les faibles valeurs enregistrées pour les kystes de dinoflagellés dans le sédiment où le maximum enregistré a été de l’ordre de 229 kystes g-1. Une part importante de l’ultraplancton a été représentée par le nanophytoplancton et les hétérotrophes procaryotes, dépassant largement les concentrations microphytoplanctoniques, ce qui est un indice de l’eutrophisation du milieu. Des corrélations hautement significatives ont été trouvées entre le microphytoplancton et les organismes microzooplanctoniques évoquant un probable rôle de ces derniers dans le contrôle des proliférations microalguales nuisibles. / We explored the distribution of the microphytoplankton community in relation to both abiotic (temperature, salinity and nutrients) and biotic factors (epiphytes microalgae, dinoflagellate cysts, ultraplankton and ciliates) in Ghar al Melh Lagoon at 5 stations during (i) a biweekly sampling from January 2011 to January 2012 and (ii) a seasonal sampling from november 2012 to march 2013. The results pointed out a seasonal variation of all parameters with high water temperature and salinity in summer and exceptional concentrations of nutrients in autumn and winter. Microphytoplankton was mainly dominated by dinoflagellates and diatoms with sequences of harmful species proliferation attaining more than 70 % of total phytoplankton. These sporadic proliferations occurred throughout the year with exacerbation in the inner parts of the lagoon mainly related to temperature and total nitrogen, nitrogen and orthophosphate. An important contribution of epiphytic species to phytoplankton abundance was recorded with especially the presence of the toxic dinoflagellate Prorocentrum lima. Microphytoplankton was dominated by Prorocentrum micans (> 28 %) and other non-cyst former species consistent with the low dinoflagellate cysts found at sediment surface (maximum = 229 cysts g-1 DS). Urtraplankton was chiefly represented by nanophytoplankton and heterotrophic prokaryotes, with low microphytoplanktonic abundance. This indicates that the lagoon is undergoing eutrophication. Significant correlations were reported between phytoplankton and microzooplankton suggesting a potential role of the former in controlling harmful microalgae proliferations.

L’objectif de ce travail de thèse est d’évaluer le degré de contamination des différents compartiments du site de la décharge d’Étueffont à savoir : les lixiviats, les sédiments, l’eau souterraine, les poissons, les insectes et les microorganismes de la décharge d’Étueffont. Ce travail de recherche est structuré en neuf chapitres.Après une première partie (Part I) consacrée à une étude bibliographique, le deuxième chapitre (Part II) présente le site d’étude, c’est-à-dire l’installation de stockage de déchets non dangereux(ISDND) d’Étueffont. La troisième partie (Part III) est consacrée à l’analyse de la qualité des lixiviats dans les lagunes, les unités de stockage des déchets « Nouveau casier », « Sous casier », « Ancienne décharge », les ruisseaux du gros Pré et Mont Bonnet. La quatrième partie (Part IV) intitulée « Contamination métallique des sédiments du site de la décharge d’Étueffont », aborde l’étude de la variation spatiotemporelle des éléments traces métalliques au niveau des lixiviats et des sédiments dans les quatre lagunes du site de la décharge d’Étueffont. Afin de déterminer le degré de contamination métallique des lixiviats et des sédiments, nous avons procédé à un suivi de certains éléments localisés en amont, au milieu et en aval de chaque lagune avec un pas d’échantillonnage trimestriel entre octobre 2013 et avril 2016. La cinquième partie (Part V), complémentaire du chapitre précédent, définit plus précisément la distribution spatiale du panache à travers l’analyse de la qualité de l’eau souterraine au moyen de piézomètres. La sixième partie (Part VI) concerne les effets des métaux lourds sur les échanges gazeux et la fluorescence des chlorophylles chez (Typha latifolia). Le septième chapitre (Part VII) est consacré à l’étude des microorganismes de la décharge d’Etueffont : apport de la cytométrie en flux. Dans le huitième chapitre (Part VIII), nous aborderons l’étude de la bioaccumulation des éléments traces métalliques dans le Chironome Chironomus riparius. La dernière partie (Part IX) intitulée « Étude de la bioaccumulation des éléments traces métalliques au niveau des différents organes du gardon Rutilus rutilus», aborde l’étude de la bioaccumulation des éléments traces métalliques au niveau de différents organes (muscle, foie, arêtes et branchies). / The objective of this thesis work is to estimate the contamination level in the various compartments of the Étueffont discharge site namely: leachates, sediments, groundwater, fishes and insects. The microorganisms (< 10 µm) of the Étueffont discharge of were investigated at the single cell level by flow cytometry. This research work is structured in nine chapters.The first part (Part I), is dedicated to a literature review. Part II presents the study site, the storage of non-hazardous waste (ISDND) at Étueffont. Part III is dedicated to the analysis of leachate quality in lagoons, NC, SC, AD, MB and GP. Part IV addresses "Metal Sediment Contamination of Étueffont discharge site" It concerns the study of spatial and temporal variation of trace metals in leachate and sediment in the four lagoons landfill site of Étueffont. To determine the metal contamination level in leachate and sediment, we conducted follow-elements located upstream, middle and downstream in each lagoon with quarterly sampling between October 2013 and April 2016. Part V complements the previous chapter, by specifically defining the spatial distribution of the plume through the quality analysis of the piezometer groundwater. Part VI addresses the heavy metals impacts on gas exchange and chlorophyll fluorescence in (Typha latifolia). Part VII is dedicated to the microorganisms (<10 µm) investigation in the Étueffont discharge: by using flow cytometry. In the (Part VIII), we addressed the study of bioaccumulation of trace metallic elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd and Pb) in insect Chironomus riparius. Part IX entitled "Study bioaccumulation of trace metals in the various organs of roach Rutilus rutilus" concerns bioaccumulation of trace metals in different organs (muscle, liver, bones and gills) of this fish.