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.

Dans les dernières décennies, la plupart des pays du monde ont connu une pénurie d'eau et l’augmentation du taux de consommation. Aujourd'hui, tous les pays dans le monde essayent de trouver des alternatives pour remédier à cette pénurie. Une solution consiste en la réutilisation des eaux grises (GW) pour l'irrigation après traitement. Les GW correspondent aux eaux usées générée dans une maison à l'exception de l'eau des toilettes. Les risques associés à la réutilisation de ces eaux est la présence de microorganismes pathogènes qui peuvent infecter les humains, les animaux et les plantes. Dans cette thèse centrée sur l'étude de la survie des représentants d'agents pathogènes, comme E. coli, P. aeruginosa, et le bactériophage MS2 qui sont trouvés dans les eaux grises. Il a été étudié l’effet de quelques facteurs physico-chimiques tels que; température (6 ± 2,23 ± 2 et 42 ± 2 ° C), la salinité (1,75 and 3.5% de NaCl), de l'oxygène (aérobie et anaérobie), des éléments nutritifs (milieu riche et de milieux pauvres), la lumière avec la photocatalyse (lampes UV et visible) et filtre à sable lent (sable du désert égyptien et le sable piscine). Une combinaison de la température, la lumière du soleil et de haute photocatlysis sont principalement responsables de la baisse rapide des bactéries et du coliphage MS2. Le filtre à sable lent a une influence nettement moindre sur la survie des bactéries dans les eaux grises, mais il est efficace pour diminuer la turbidité et de la DCO. / In recent decades, most countries of the world have experienced a shortage of water and increase its rate of consumption. Today, every country in the world are interested in this problem by trying to find alternatives to address this shortage. One solution is reuse greywater (GW) for irrigation after treatment. GW is all water generated from Household except toilet water. The risks associated with the reuse of these waters are the presence of pathogens that can infect humans, animals and plants. In this thesis focused on studying treatment by slow sand filtration and the survival of representatives of pathogens, such as E. Coli, P. aeruginosa , E. Faecalis and Bacteriophage MS2 which could be found in the greywater. The study factors was a physico-chemicals factors such as; temperature (6±2,23±2,42±2°c), salinity (1.75 and 3.5% Nacl), oxygen (aerobic and anaerobic condition), nutrient ( rich media , 50%: 50% salt and poor media ), light with photocatalysis ( UV and Visible lights) and slow sand filter (Egyptian desert sand and swimming pool sand). A combination of high temperature, sunlight and photocatlysis are mainly responsible for the rapid decline of bacteria and MS2 coliphage. Slow sand filter have clearly less influence on the survival of bacteria in the greywater, but it effective to decline turbidity and COD for short times.

The observational study on natural regeneration of Norway spruce (Picea abies) was provided during seasons 2010 and 2011 in the windthrow area of High Tatra National Park. The main aim of this master thesis was to describe the distribution pattern in Norway spruce regeneration as well as to estimate the spatial scale, which most preciselly describes the differences in its phenotypic variability. Following step was to determine the relative influence of abiotic and stand factors on the growth characteristics and abundance of spruce seedlings. The Main focus lied on stressing the role of biotic interactions, like intraspecific and interspecific competition, leading to certain discrepancies in the phenotype, as well as in abundance of spruce seedlings.The reponse in variability in spruce traits was recognized at each spatial level. The results showed clear causality between soil moisture and vegetation composition, which both directly modified not only the phenotype of spruce seedlings and plants, but have even influenced their counts on particular stands.

Les tourbières représentent 2 à 3% des terres émergées et stockent entre 10 et 25% du carbone des sols. Les tourbières sont soumises à des contraintes anthropiques et climatiques importantes qui posent la question de la pérennité de leur fonctionnement en puits de C et de leur stock. Une meilleure compréhension de ces écosystèmes est nécessaire pour déterminer les facteurs et les effets et interactions de ces facteurs sur les émissions de gaz à effet de serre (GES). Ce travail a consisté à suivre les émissions de GES et les facteurs contrôlant dans La tourbière de La Guette (Sologne) pour établir son bilan de C. En parallèle des expérimentations sur l’effet de l’hydrologie sur les flux ont été menées, enfin un suivi sur 4 sites a été réalisé pour étudier la variabilité à l’échelle journalière. Les résultats de ces travaux montrent que la tourbière de La Guette a fonctionné en source de C (-220 ± 33 gC m-2 an-1) et ce malgré un niveau de nappe élevé. Ils montrent également l’importance de la variabilité spatiale des flux estimés à l’échelle d’un site. Les expérimentations confirment l’importance de l’hydrologie et suggèrent à haut niveau de nappe d’eau des phénomènes liés au transport des gaz. Enfin l’étude de la variabilité journalière montre que la sensibilité de la respiration à la température peut être différente le jour et la nuit et que la synchronisation entre les températures du sol et la respiration peuvent améliorer la représentation de cette dernière. / Peatlands cover only 2 to 3% of the land area but store between 10 and 25% of the soil carbon. The outcome of the anthropic and climatic pressure on these ecosystems is uncertain regarding their functions and storage. A better understanding of these ecosystems is needed to determine the factors and their interactions on greenhouse gas (GHG) emission. This work consist in monitoring GHG emissions and controlling factors in a Sphagnum peatland to estimate its carbon balance. Experimentation on mesocosms were carried out to explore the effect of hydrology on the fluxes and a monitoring on 4 sites was made to study the daily variability. Results show that La Guette peatland was a carbon source (-220 ± 33 gC m-2 an-1) in spite of the high water table level. The importance of the spatial variability measured in the site was also demonstrate. The hydrology effect was confirmed by the mesocosms experiments and high water table level shows that gas transport might have an effect. Finally the study of the daily variability show that the temperature sensitivity of the respiration might be different between day and night and that synchronizing soil temperatures and respiration can improve the respiration representation.

P. roqueforti est une moisissure connue comme contaminant des ensilages et des aliments, mais aussi utilisée comme ferment pour la production de fromages à pâte persillée. Cette espèce est également connue pour son potentiel de production de métabolites secondaires à impact positif, comme les arômes, mais aussi à impact négatif, tels que des mycotoxines (dont la roquefortine C -ROQC- et l’acide mycophénolique -MPA-). Dans la première partie de ce travail, l’occurrence de la ROQC, du MPA et de l’aflatoxine M1 (seule mycotoxine réglementée dans les produits laitiers), dans une collection de 86 fromages à pâte persillée de différentes variétés et origines géographiques (15 pays), a été réalisée. Il apparaît que, si l’aflatoxine est inférieure au seuil de détection (LOD) de la méthode, les concentrations en ROQC et MPA sont quant à elles très variables et qu’une co-occurrence de ces mycotoxines existe dans 51% des échantillons testés. Dans la seconde partie, la toxicité de ces mycotoxines sur modèles cellulaires intestinal ou monocytaires a été évaluée. L’étude de cytotoxicité en mono-exposition a permis d’établir des valeurs de référence (CI50); d’autre part, un effet synergique des deux mycotoxines aux plus fortes concentrations testées a été révélé sur la lignée cellulaire intestinale (Caco-2). L’implication du mécanisme apoptotique après une exposition précoce (3 et 6 heures) à la ROQC et/ou au MPA a aussi été mise en évidence sur le modèle THP-1 ainsi qu’une absence d’implication de l’apoptose après 24 heures de mono ou de co-exposition sur modèle intestinal Caco-2. Enfin, dans la troisième partie, une étude de facteurs biotique ou abiotiques pouvant potentiellement moduler la production de ROQC et de MPA a été réalisée. L’évaluation du potentiel mycotoxigénique de 96 souches de P. roqueforti a mis en évidence que le milieu cheese-agar (mimant la composition physico-chimique du fromage) était beaucoup moins favorable que le milieu YES pour la production des deux mycotoxines et une grande variabilité dans la capacité de production des souches a été observée. L’étude de l’influence des facteurs abiotiques a montré qu’une température de 12°C ou une concentration en NaCl de 8% ou encore une atmosphère contenant 5% d’O2 diminuait significativement la production de ROQC et de MPA indépendamment de la croissance, alors que les autres facteurs (pH et présence de précurseurs de la ROQC) n’avaient pas d’effet dans les conditions testées. / P. roqueforti is a mould associated with silage and food contamination but also used as a ripening culture for the production of blue-veined cheese. Moreover, this species is also known for its potential to produce secondary metabolites. These metabolites can have a positive impact (e.g. aromas) or a negative impact (e.g. mycotoxins, including roquefortine C -ROQC- and mycophenolic acid -MPA-). In the framework of this work, we first studied the occurrence of MPA, ROQC and aflatoxin M1 (the only regulated mycotoxin in dairy products) within an 86 blue-veined cheese collection (representing 15 countries). Aflatoxin contents were always below the method detection limit. For MPA and ROQC, concentrations were highly variable and a co-occurrence of both mycotoxins was observed in 51% of the tested samples. Then, the toxicity of the 2 mycotoxins was established on various cell models (intestinal and monocytic). Mono-exposure studies allowed IC50 determination. Moreover, a synergistic effect was observed on Caco-2 cells when MPA and ROQC were used for co-exposure at the highest tested concentrations. While an apoptotic mechanism was observed at early THP-1 exposure stages (3 and 6h), no apoptose occurred for Caco-2 cells after 24 h of mono or co-exposure. Finally, a study of the biotic and abiotic factors potentially modulating P. roqueforti MPA and ROQC production was performed. Mycotoxigenic potential evaluation of 96 de P. roqueforti strains highlighted that a cheese-agar medium (mimicking cheese physico-chemical composition) was less favourable than the synthetic YES medium for mycotoxin production. A large variability in terms of mycotoxin production was also observed among the tested strains. Besides, while a significant effect of the temperature (12°C) and NaCl (8%) and O2 (5%) concentrations was observed on ROQC and MPA production, no significant effect of pH and ROQC amino-acid precursor addition could be detected on the production of both mycotoxins.

Habitat selection, territorial behaviour and reproductive behaviour of dragonflies (Odonata) are discussed and biotic and abiotic factors affecting their territorial and reproductive behaviour are reviewed. The most important biotic factors are predation risk affecting larval survival and the presence of aquatic vegetation, which provides spatial structure. The review is complemented by a field study of territorial and reproductive behavior of dragonflies at an experimental site, at which the quality of individual pools was manipulated by a combination of the presence or absence of artificial vegetation and the presence or absence of an introduced top predator (late-instar larvae of Anax and Aeshna).

Made available in DSpace on 2014-12-17T14:02:00Z (GMT). No. of bitstreams: 1 EudrianoFSC_DISSERT.pdf: 4107766 bytes, checksum: 4869c74d441a0dacea2217f661f2635e (MD5) Previous issue date: 2010-04-29 / Knowledge of the environmental factors influence on the spatial-temporal variation of fishes is important to fisheries management and conservation. Thus, the aim of this work was to analyze the influence of the abiotical factors on the spatial-temporal distribution of Paralonchurus brasiliensis (Pisces, Sciaenidae) caught by-catch with the shrimp fishing of Ubatuba and Caraguatatuba regions, north coast of S?o Paulo State. The fishes were captured every month from January to December 2002. Samples were collected by otter trawl at 5, 10, 15, 20, 25, 30 and 35m depths. The temperatures (surface and bottom), salinities (surface and bottom), sediment features and organic matters were verified for each depth. During all period of the study 12.642 specimens of P. brasiliensis were captured at Ubatuba and 17.166 at Caraguatatuba, which totalized the biomass of 267 for the first and 339kg for the other region. The females outnumbered males in fish population. The greatest values of biomass and number of individuals were registered at the summer and autumn seasons, while the lowest values were observed at the winter and spring seasons. The greatest abundances were found from 15 to 25m depth. In this study, it was verified that P. brasiliensis is a coastal waters associate species. The spatialtemporal distribution of P. brasiliensis is affected by intrusion of SACW and depth for the coastal region and by depth and sediment in sheltered areas such as Caraguatatuba / A compreens?o dos processos ambientais que controlam a distribui??o espa?o-temporal dos peixes ? de fundamental import?ncia para o manejo e conserva??o dos estoques pesqueiros. Desse modo, o presente trabalho analisou a influ?ncia dos fatores ambientais sobre a varia??o espa?o-temporal de Paralonchurus brasiliensis (Pisces, Sciaenidae) componente da fauna acompanhante da pesca de camar?es nas regi?es de Ubatuba e Caraguatatuba, litoral norte do estado de S?o Paulo. As capturas foram realizadas mensalmente, durante o per?odo de janeiro a dezembro de 2002, nas is?batas de 5, 10, 15, 20, 25, 30 e 35m com o aux?lio de um barco de pesca camaroneiro equipado com redes do tipo mexicanas. A temperatura (superf?cie e fundo), salinidade (superf?cie e fundo), granulometria e a quantidade de mat?ria org?nica do sedimento foram determinados em cada transecto. Foram capturados 12.642 esp?cimes de P. brasiliensis na regi?o de Ubatuba e 17.166 em Caraguatatuba, correspondendo a uma biomassa total de 267 e 339kg, respectivamente. As f?meas predominaram na popula??o. Os maiores valores de biomassa e n?mero total de indiv?duos capturados ocorreram durante o ver?o e outono, e os menores no inverno e primavera. As maiores abund?ncias ocorreram em profundidades entre 15 e 25m. Constatouse que P. brasiliensis ? uma esp?cie associada a ?guas costeiras. A intrus?o da ACAS e a profundidade s?o fatores ambientais preponderantes que influenciam na distribui??o espa?o-temporal de P. brasiliensis na regi?o de Ubatuba, enquanto a profundidade e o tipo de sedimento exercem maior influ?ncia em ?reas abrigadas como Caraguatatuba

The European rewardless orchid Dactylorhiza sambucina commonly produces yellow- and purple-flowered individuals in frequencies that in different populations range from balanced to very unbalanced ones (we can find even monochromatic populations). I studied an effect of abiotic factors (soil pH, hydrolimits, slope and altitude of the locality), biotic factors (weight and viability of the seeds obtained from crossing between and within morphs) and the size of the populations on corolla colour of two morphs in European populations (the Czech Republic, Italy, Austria, Germany, France).

Made available in DSpace on 2017-07-10T18:13:30Z (GMT). No. of bitstreams: 1 Patricia S da Silva.pdf: 3404031 bytes, checksum: 5e4338885b036077d4619e4525d56526 (MD5) Previous issue date: 2011-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this study was to analyze spatial and temporal patterns of ichthyoplankton in tributaries (Aguapeí, Verde, Pardo and Anhanduí) of Porto Primavera Reservoir, Upper Paraná River, Brazil, and its relation to some environmental variables. Specifically we sought to (I) assess whether the tributaries have similar abiotic characteristics, (II) verify that abiotic factors have more influence in the spawning of the species, (III) investigate if the species have preference for tributaries, and (IV) analyze whether the tributaries of the Porto Primavera Reservoir are really suitable environments for reproduction of fish species, especially long-distance migratory drastically affected by impoundments. Samples were taken monthly during three spawning seasons (October to March from 2007 to 2010), through horizontal hauls on the water surface at dusk, with a plankton net. The principal component analysis (PCA) was used to ascertain whether the abiotic variables differed among the tributaries. The influence of environmental variables (water temperature, pH, electrical conductivity, dissolved oxygen, turbidity, water level and discharge) in the abundance of eggs and larvae was determined using the Bioenv procedure. The Kruskal-Wallis (KW) was applied to verify spatial (tributaries: rivers Aguapeí, Verde, Pardo and Anhanduí; and habitats: main channel and lagoon) and temporal distribution patterns (month: October, November, December, January, February, and March, and spawning seasons: 1 =2007/2008, 2=2008/2009, and 3=2009/2010). The characteristic taxa of each tributary were identified through Indicator Species Analysis (IndVal). A total of 49,072 eggs, 63,857 larvae were captured. The variable that best correlated with the distribution and abundance of ichthyoplankton was the water discharge. The highest densities of eggs were noted for the Verde river, however larvae did not differ significantly among the tributaries. Eggs had the highest densities in the main channel and while larvae in lagoons. High catches of ichthyoplankton were observed from November to January, but with a peak in December. Abundance of eggs were higher in the 2009/2010 spawning season, however the larvae did not differ among spawning season. The species composition varies along the tributaries and each river has a group of indicator species. In main channel of the rivers were mainly found larvae of migratory species of short distance and long-distance and in the lagoons mainly sedentary or migratory species of short distances. The tributaries assessed are spawning grounds for many fish species and can be considered suitable for the reproduction of many long-distance migratory species. Establishment and enlargement of Conservation Units in tributaries of Porto Primavera reservoir, can help preserve habitats identified as essential spawning and nursery areas, and can be key to the maintenance and conservation of the fish species in the upper Paraná River basin. / O objetivo deste trabalho foi analisar padrões espaciais e temporais do ictioplâncton em tributários (Aguapeí, Verde, Pardo e Anhanduí) do reservatório de Porto Primavera, alto rio Paraná, Brasil, e sua relação com algumas variáveis ambientais. Especificamente procurou se (I) Avaliar se os tributários apresentam características abióticas similares, (II) Verificar que fatores abióticos exercem maior influência na desova das espécies, (III) Averiguar se há preferência das espécies de peixes quanto aos tributários, e (IV) Analisar se os tributários do reservatório de Porto Primavera realmente são ambientes adequados à reprodução das espécies de peixes, em especial as migradoras de longa distância drasticamente afetadas pelos represamentos. As amostragens foram realizadas durante três estações reprodutivas sucessivas (outubro a março de 2007 a 2010), ao anoitecer com rede de plâncton. A análise de componentes principais (ACP) foi empregada para averiguar se as variáveis abióticas diferiam entre os tributários. A influência das variáveis ambientais (temperatura da água, pH, condutividade elétrica, oxigênio dissolvido, turbidez, nível e vazão) na abundância de ovos e larvas foi determinada através do procedimento Bioenv. O teste de Kruskall Wallis (K-W) foi aplicado para verificar padrões de distribuição espacial (tributários: rios Aguapeí, Verde, Pardo e Anhanduí; e habitats: rio e lagoa) e temporal (meses: outubro, novembro, dezembro, janeiro, fevereiro e março; e estações reprodutivas: 1 = 2007/2008, 2 = 2008/2009 e 3 = 2009/2010). Os táxons característicos de cada tributário foram identificados por meio da Análise de Espécies Indicadoras (IndVal). Um total de 49.072 ovos, 63.857 larvas foi capturado. A variável que melhor se correlacionou com a distribuição e abundância do ictioplâncton foi a vazão. As maiores densidades de ovos foram verificadas para o rio Verde, porém as de larvas não diferiram significativamente entre os tributários. Ovos apresentaram maiores densidades nos rios e as larvas nas lagoas. Capturas elevadas do ictioplâncton foram observadas de novembro a janeiro, porém com pico em dezembro. As capturas de ovos se sobressaíram na estação reprodutiva de 2009/2010, no entanto, as de larvas não diferiram entre as estações reprodutivas. A composição das espécies ao longo dos tributários varia e cada rio apresenta um grupo de espécies indicadoras. Nos rios foram encontrados principalmente larvas de espécies migradoras de curta e longa distância e nas lagoas principalmente de espécies sedentárias ou migradoras de curta distância. Os tributários analisados atuam como área de desova de várias espécies de peixes e podem ser considerados propícios para a reprodução de várias espécies migradoras de longa distância. A criação e ampliação de Unidades de Preservação Permanente nos tributários do reservatório de Porto Primavera podem auxiliar na preservação dos habitats identificados como áreas essenciais para a desova e berçário, e pode ser a chave para a manutenção e conservação das espécies de peixes na bacia do alto rio Paraná.

Department of Geography and Geo-Information Sciences / MENVSC