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Análise molecular das estruturas e diversidade de comunidades microbianas em solo de manguezal preservado da Ilha do Cardoso-SP / Molecular analysis of the structures and diversity of microbial communities in soil of preserved mangroves of Ilha do Cardoso-SPMendes, Lucas William 27 August 2009 (has links)
Os manguezais tropicais são considerados um dos ecossistemas mais produtivos do mundo, sendo caracterizados pela alta taxa de ciclagem de matéria orgânica e nutrientes que ocorre entre os oceanos e os ambientes terrestres. Embora os manguezais sejam considerados áreas de proteção ambiental, a destruição desses ambientes é progressiva, devido a atividades industriais e portuárias nos estuários. Nos manguezais, a ciclagem de nutrientes está diretamente relacionada às atividades e a diversidade das comunidades microbianas presentes no solo. Este trabalho está inserido em um projeto mais amplo dentro do programa BIOTA/FAPESP, no que tange aos estudos da biodiversidade no Estado de São Paulo e utilização dessa biodiversidade de modo sustentável. O objetivo deste trabalho foi avaliar as estruturas e diversidade das comunidades de Bacteria, Archaea e Fungi presentes no solo de manguezal preservado da Ilha do Cardoso-SP. As amostras foram analisadas pelas técnicas de T-RFLP, ARISA, clonagem e seqüenciamento a fim de obter uma caracterização das estruturas das comunidades microbianas de uma área de manguezal preservado em comparação com os ambientes adjacentes de restinga e floresta e também a um manguezal antropizado. Os resultados permitiram concluir que o manguezal possui características exclusivas, com a presença de organismos distintos, revelando um possível potencial biotecnológico a ser explorado. Adicionalmente, os dados revelaram que a ação antrópica afetou as estruturas dessas comunidades de modo a ser notada uma sensível diminuição de diversidade no manguezal antropizado, evidenciando, dessa maneira, a importância da preservação desse ecossistema / The tropical mangroves are considered one of the most productive ecosystems of the world, being characterized by the high tax of organic matter and recycling of nutrients, that happens between the oceans and the terrestrial habitats. Although the mangroves are considered areas of environmental protection, the destruction of those ecosystems is progressive, due to industrial and port activities in the estuaries. In mangroves, the recycling of nutrients is directly related to the activities and to the diversity of microbial communities present in the soil. This work is part of a wider project inside of the program BIOTA/FAPESP, with respect to the studies of the biodiversity in the State of São Paulo and use of that biodiversity in a maintainable way. The objective of this work was to evaluate the structures and diversity of communities of Bacteria, Archaea and Fungi present in the soil of preserved mangrove of Ilha do Cardoso-SP. The samples were analyzed by T-RFLP and ARISA techniques, cloning and sequencing in order to obtain a characterization of the microbial communities structure of preserved mangrove area in comparison with the adjacent environments of restinga (tropical moist forest) and forest and also to a degraded mangrove. The results allowed concluding that the mangroves present exclusive characteristics, with the presence of distinct organisms, revealing a possible biotechnological potential to be explored. Additionally, the data revealed that the human action affected the structures of those communities in a way to be noticed a sensitive diversity decrease in the degraded mangrove, evidencing, this way, the importance of the ecosystem preservation
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Análise molecular das estruturas e diversidade de comunidades microbianas em solo de manguezal preservado da Ilha do Cardoso-SP / Molecular analysis of the structures and diversity of microbial communities in soil of preserved mangroves of Ilha do Cardoso-SPLucas William Mendes 27 August 2009 (has links)
Os manguezais tropicais são considerados um dos ecossistemas mais produtivos do mundo, sendo caracterizados pela alta taxa de ciclagem de matéria orgânica e nutrientes que ocorre entre os oceanos e os ambientes terrestres. Embora os manguezais sejam considerados áreas de proteção ambiental, a destruição desses ambientes é progressiva, devido a atividades industriais e portuárias nos estuários. Nos manguezais, a ciclagem de nutrientes está diretamente relacionada às atividades e a diversidade das comunidades microbianas presentes no solo. Este trabalho está inserido em um projeto mais amplo dentro do programa BIOTA/FAPESP, no que tange aos estudos da biodiversidade no Estado de São Paulo e utilização dessa biodiversidade de modo sustentável. O objetivo deste trabalho foi avaliar as estruturas e diversidade das comunidades de Bacteria, Archaea e Fungi presentes no solo de manguezal preservado da Ilha do Cardoso-SP. As amostras foram analisadas pelas técnicas de T-RFLP, ARISA, clonagem e seqüenciamento a fim de obter uma caracterização das estruturas das comunidades microbianas de uma área de manguezal preservado em comparação com os ambientes adjacentes de restinga e floresta e também a um manguezal antropizado. Os resultados permitiram concluir que o manguezal possui características exclusivas, com a presença de organismos distintos, revelando um possível potencial biotecnológico a ser explorado. Adicionalmente, os dados revelaram que a ação antrópica afetou as estruturas dessas comunidades de modo a ser notada uma sensível diminuição de diversidade no manguezal antropizado, evidenciando, dessa maneira, a importância da preservação desse ecossistema / The tropical mangroves are considered one of the most productive ecosystems of the world, being characterized by the high tax of organic matter and recycling of nutrients, that happens between the oceans and the terrestrial habitats. Although the mangroves are considered areas of environmental protection, the destruction of those ecosystems is progressive, due to industrial and port activities in the estuaries. In mangroves, the recycling of nutrients is directly related to the activities and to the diversity of microbial communities present in the soil. This work is part of a wider project inside of the program BIOTA/FAPESP, with respect to the studies of the biodiversity in the State of São Paulo and use of that biodiversity in a maintainable way. The objective of this work was to evaluate the structures and diversity of communities of Bacteria, Archaea and Fungi present in the soil of preserved mangrove of Ilha do Cardoso-SP. The samples were analyzed by T-RFLP and ARISA techniques, cloning and sequencing in order to obtain a characterization of the microbial communities structure of preserved mangrove area in comparison with the adjacent environments of restinga (tropical moist forest) and forest and also to a degraded mangrove. The results allowed concluding that the mangroves present exclusive characteristics, with the presence of distinct organisms, revealing a possible biotechnological potential to be explored. Additionally, the data revealed that the human action affected the structures of those communities in a way to be noticed a sensitive diversity decrease in the degraded mangrove, evidencing, this way, the importance of the ecosystem preservation
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Dynamics of marine pelagic bacterial communities on the Texas-Louisiana shelfAnitsakis, Erin Colleen 15 May 2009 (has links)
Microbial community interactions within many ecosystems are still relatively
unknown. Investigating links between environmental dynamics and shifting pelagic
bacterial community structures on the Texas-Louisiana shelf, Eubacterial community
profiles of Operational Taxonomic Units (OTUs) were generated using Automated
Ribosomal Intergenic Spacer Analysis (ARISA) of the 16S rDNA and 23S rDNA
intergenic spacer region. This ITS region is highly variable in both length and sequence.
Community diversity was assessed by the comparison of ARISA-generated community
fingerprints of samples collected from four distinct regions along the Texas-Louisiana
shelf in a cross-shelf pattern on 10m, 20m, and 40m isobaths.
Incubations of samples with a thymidine analog, 5-Bromodeoxyuridine (BrdU),
allowed for the isolation and analysis of the actively growing subset within the total
bacterial population. Community composition was determined through the construction
of clone libraries for sequencing and putative phyla affiliation of community 16 rRNA
genes. Hydrographic data were also collected for analysis of shifts in microbial
community diversity correlated with a variety of influential environmental factors.
ARISA profiles of Eubacterial species richness suggest strong distinction between the
two communities found within Zones A and C along the Texas-Louisiana Shelf.
Further analysis of salinity gradients originating from the two main fluvial
sources, the Mississippi and the Atchafalaya Rivers, identified possible sources of
variation between the individual communities. Whereas composition of these communities remains discrete between regions, the active subset of the population
becomes more similar across the shelf through the summer. Possibly due to undersampling
of hypoxic sites, no relationship could be determined between hypoxia
formation and the Eubacterial community dynamics. Several OTUs within the
communities were identifiable as α - and β - Proteobacteria, Actinobacteria,
Synechococcus, Prochlorococcus, and Cytophaga/Flavobacterium/Bacteroides.
Through validation studies of 5-Bromodeoxyuridine field sampling, this study
indicates the power of BrdU incorporation and ARISA analysis to study a dynamic
environmental system and explore the factors that determine the structure of the pelagic
community on the Texas-Louisiana Shelf.
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Acquisition de tolérance et modification de structure des communautés périphytiques : une réponse précoce à la pression urbaine dans les milieux aquatiques / Tolerance acquisition and structure modification of periphytic communities : an early-warning response to urban contamination of aquatic ecosystemsFechner, Lise 14 December 2010 (has links)
La contamination des milieux aquatiques urbains se caractérise aujourd'hui par un mélange de micropolluants d'origines et de types variés. Les conséquences de ce type de contamination, multiples mais faibles et chroniques, sur les écosystèmes aquatiques sont difficiles à évaluer. En effet, il est difficile d'une part de dresser un état des lieux précis de la contamination et d'autre part, de relier cette contamination à la réponse biologique des organismes exposés puisqu'elle n'engendre pas nécessairement des effets visibles et immédiats. Cette étude a pour objectif de développer une méthodologie permettant d'utiliser le périphyton pour évaluer l'impact d'une contamination urbaine typique. Les biofilms sont des communautés aquatiques complexes jouant un rôle primordial dans le fonctionnement des écosystèmes aquatiques. Leur réponse biologique à une perturbation peut s'évaluer au niveau structurel comme au niveau fonctionnel. Une première étape de ce travail a consisté à développer d'une part un test de toxicité aiguë permettant d'évaluer la tolérance de la composante hétérotrophe des biofilms selon le concept PICT, et d'autre part l'utilisation de la technique d'empreinte génétique ARISA pour évaluer des modifications de structure des communautés bactériennes et eucaryotes des biofilms. Les méthodologies développées ont ensuite été testées au laboratoire par des expositions de périphyton à des métaux à des concentrations environnementales. Par la suite, elles ont pu être déployées in situ : d'abord dans un gradient de contamination multi-métallique sur la Seine avec des prélèvements ponctuels de biofilms naturels ainsi qu'une expérience de transposition (amont/aval de l'agglomération parisienne). Enfin, le lien entre la tolérance du périphyton et la contamination métallique globale du milieu a été exploré à l'échelle d'un bassin versant. Les résultats sont prometteurs quant à l'utilisation du périphyton pour évaluer l'impact d'une contamination urbaine / Urban aquatic ecosystems are these days contaminated by mixtures of micropollutants of diverse types and origins. Such contaminations, which are multiple, chronic and non-lethal, raise increasing concern among the scientific community. Indeed, a precise evaluation of exposure levels is difficult to obtain. Moreover, establishing a causal link between contamination and the induced biological response of aquatic organisms is complex as no direct and visible effects can be observed. The aim of this study is to develop a methodology for the use of periphyton as a biomarker of urban pollution. Biofilms are complex aquatic communities and play an important role in aquatic ecosystems. Their response to a disruption can be assessed both in terms of structure or functional modifications. Our first step was to develop both a PICT approach with a new short-term toxicity test to measure the tolerance to metal of the heterotrophic component of biofilms and the use of a fingerprinting technique (ARISA) to reveal structure modifications of both bacterial and eukaryotic communities. The methodologies thus developed were tested in a microcosm study by exposing periphyton to metals at environmental levels. They were then used in field studies: first in a multi-metallic gradient along the Seine river by punctual sampling of natural periphyton and also in a translocation study (upstream/downstream the Paris urban area). Furthermore, the link between biofilm tolerance levels and the global metallic contamination was explored at the watershed scale. It is hoped that the future use of this approach will help to understand the impacts of human activities, especially toxic pressure, on aquatic ecosystems
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Diversidade de cianobactérias em manguezais do Estado de São Paulo / Cyanobacterial diversity from São Paulo State mangrovesRigonato, Janaina 09 August 2010 (has links)
Os micro-organismos desempenham importante papel na reciclagem dos elementos em ecossistemas de manguezais, uma vez que como produtores primários podem controlar reações químicas. O grupo particular das cianobactérias atua promovendo a entrada de carbono e nitrogênio por meio da sua capacidade de realizar fotossíntese oxigênica e fixação de nitrogênio atmosférico. No Brasil, as florestas de manguezais ocupam uma área de aproximadamente 25.000 km2 e no Estado de São Paulo, 240 km2 da área total está coberta por este ecossistema. O objetivo deste trabalho foi avaliar a diversidade de cianobactérias que colonizam as folhas de Avicennia schaueriana, Rhizophora mangle e Laguncularia racemosa do manguezal da Ilha do Cardoso, um ambiente pristino, bem como acessar e comparar a população de cianobactérias dos solos dos manguezais da Ilha do Cardoso e de Bertioga, este último contaminado com óleo bruto. Para este propósito, as técnicas de DGGE e biblioteca de clone do gene RNAr 16S, ARISA e TRFLP do gene nifH foram utilizadas. Os resultados da filosfera evidenciaram uma sutil influência do gênero de árvore na colonização das cianobactérias, entretanto, um forte efeito da localização destas dentro do manguezal foi observado. As folhas das árvores do meio da área de manguezal apresentaram uma maior diversidade de gêneros de cianobactérias. No geral, foram identificados 19 gêneros e várias sequências de cianobactérias não cultiváveis. Uma predominância de sequências com alta similaridade com representantes das ordens Nostocales e Oscillatoriales foi observada. Sequências com identidade com o gênero Symphyonemopsis (ordem Stigonematales) foram recuperadas em maiores quantidade. Com relação à diversidade no solo, os resultados de DGGE e ARISA demonstraram que a população de cianobactérias é distinta entre os manguezais estudados, porém os perfis eletroforéticos das amostras coletadas próximo ao mar se agruparam, sugerindo que a colonização é influenciada pelas condições de inundação. O perfil mais diferente foi obtido no ponto próximo à floresta no manguezal de Bertioga, local mais afetado pela contaminação de óleo. As bibliotecas de clones claramente indicaram diferenças das sequências do gene RNAr 16S entre os pontos amostrados. Um total de 99 UTOs foi obtido, com 61 "singletons". Na localidade próxima ao mar os gêneros Procholorococcus e Synechococcus foram dominantes em ambos os manguezais. A maioria das sequências de RNAr 16S encontradas nos outros pontos foram relacionadas com cianobactérias não cultiváveis. A diversidade alfa sugeriu que o local com menor diversidade foi o meio do manguezal de Bertioga, e o maior foi em Bertioga próximo à floresta, os demais pontos tiveram valores similares. Os maiores índices de riqueza foram encontrados nos pontos próximos à floresta, enquanto menores valores foram observados nos pontos próximos ao mar. A maioria das sequências de RNAr 16S obtidas em Bertioga no meio do manguezal e próximo à floresta tiveram identidades menores do que 90% com as disponíveis no GenBank. Estas sequências podem representar novos táxons ou cianobactérias conhecidas, porém ainda não sequenciadas. O TRFLP do gene nifH indicou que os locais próximos ao mar e meio do manguezal na Ilha do Cardoso abrigaram populações de diazotróficos semelhantes, enquanto que em Bertioga estes pontos apresentaram diferenças nos perfis de TRFLP. As maiores diferenças estavam nos locais próximos à floresta em ambos os manguezais. / Microorganisms play important role in the recycling of elements in mangrove ecosystems, since as primary producers they can control chemical reactions. The particular cyanobacteria group act promoting the input of carbon and nitrogen through their ability to realize oxygenic photosynthesis and fixing atmospheric nitrogen. In Brazil, the mangrove forests occupy an area of approximately 25.000 km2, and in the total area of São Paulo State, 240 km2 are covered by this ecosystem. The aim of this work was to evaluate the cyanobacterial diversity that colonize Avicennia schaueriana, Rhizophora mangle and Laguncularia racemosa leaves from Cardoso Island mangrove, a pristine site, as well as to assess and compare the soil cyanobacterial population from both Cardoso Island and Bertioga mangroves, this last one contaminated with crude oil. For this purpose, the techniques of DGGE and clone library of 16S rRNA gene, ARISA, and TRFLP of nifH gene were used. The phyllosphere results evidenced a subtle difference of the genus of tree on the colonization of cyanobacteria, however a strong effect from trees location within the mangrove was observed. The tree leaves from the middle of mangrove area showed a greater diversity of cyanobacterial genera. In geral, 19 genera and several uncultivated cyanobacteria were identified. A predominance of sequences with high similarities to representatives of the order Nostocales and Oscillatoriales were observed. Sequences with similarities to the genus Symphyonemopsis (order Stigonematales) were recovered in higher quantity. Regarding to the soil diversity, DGGE and ARISA results showed that the cyanobacterial population is distinct among both mangroves studied, however the electrophoretic profiles from samples collected near to the sea grouped together, suggesting that colonization is influenced by flood conditions. The most different profile was obtained in the site near to the forest in Bertioga mangrove, location more affected by the oil contamination. Clone libraries clearly showed 16S rRNA sequences differences among sites sampled. A total of 99 OTUs were obtained, with 61 singletons. In the site near to the sea the Procholorococcus and Synechococcus genera were dominant in both mangroves. The majority of 16S rRNA sequences found in the other sites were related to uncultured cyanobacteria. Alpha diversity suggested that the site with lowest diversity was middle of the Bertioga mangrove, and the highest was Bertioga near to the forest, the remainder sites had similar values. The highest richness indices were found in the sites near to the forest, while lower values were observed in the sites near to the sea. The majority of the 16S rRNA sequences obtained from the middle of the mangrove and near to the forest in Bertioga showed identities lower than 90% with that available in the GenBank. These sequences may represent novel cyanobacterial taxa or known cyanobacteria not yet sequenced. The TRFLP of nifH gene indicated that the sites near to the sea and middle of the Cardoso Island mangrove harbored similar diazotrophic populations, while in Bertioga these sites presented differences in TRFLP profiles. The greatest differences were in the sites near to the forest in both mangroves.
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Diversidade de cianobactérias em manguezais do Estado de São Paulo / Cyanobacterial diversity from São Paulo State mangrovesJanaina Rigonato 09 August 2010 (has links)
Os micro-organismos desempenham importante papel na reciclagem dos elementos em ecossistemas de manguezais, uma vez que como produtores primários podem controlar reações químicas. O grupo particular das cianobactérias atua promovendo a entrada de carbono e nitrogênio por meio da sua capacidade de realizar fotossíntese oxigênica e fixação de nitrogênio atmosférico. No Brasil, as florestas de manguezais ocupam uma área de aproximadamente 25.000 km2 e no Estado de São Paulo, 240 km2 da área total está coberta por este ecossistema. O objetivo deste trabalho foi avaliar a diversidade de cianobactérias que colonizam as folhas de Avicennia schaueriana, Rhizophora mangle e Laguncularia racemosa do manguezal da Ilha do Cardoso, um ambiente pristino, bem como acessar e comparar a população de cianobactérias dos solos dos manguezais da Ilha do Cardoso e de Bertioga, este último contaminado com óleo bruto. Para este propósito, as técnicas de DGGE e biblioteca de clone do gene RNAr 16S, ARISA e TRFLP do gene nifH foram utilizadas. Os resultados da filosfera evidenciaram uma sutil influência do gênero de árvore na colonização das cianobactérias, entretanto, um forte efeito da localização destas dentro do manguezal foi observado. As folhas das árvores do meio da área de manguezal apresentaram uma maior diversidade de gêneros de cianobactérias. No geral, foram identificados 19 gêneros e várias sequências de cianobactérias não cultiváveis. Uma predominância de sequências com alta similaridade com representantes das ordens Nostocales e Oscillatoriales foi observada. Sequências com identidade com o gênero Symphyonemopsis (ordem Stigonematales) foram recuperadas em maiores quantidade. Com relação à diversidade no solo, os resultados de DGGE e ARISA demonstraram que a população de cianobactérias é distinta entre os manguezais estudados, porém os perfis eletroforéticos das amostras coletadas próximo ao mar se agruparam, sugerindo que a colonização é influenciada pelas condições de inundação. O perfil mais diferente foi obtido no ponto próximo à floresta no manguezal de Bertioga, local mais afetado pela contaminação de óleo. As bibliotecas de clones claramente indicaram diferenças das sequências do gene RNAr 16S entre os pontos amostrados. Um total de 99 UTOs foi obtido, com 61 singletons. Na localidade próxima ao mar os gêneros Procholorococcus e Synechococcus foram dominantes em ambos os manguezais. A maioria das sequências de RNAr 16S encontradas nos outros pontos foram relacionadas com cianobactérias não cultiváveis. A diversidade alfa sugeriu que o local com menor diversidade foi o meio do manguezal de Bertioga, e o maior foi em Bertioga próximo à floresta, os demais pontos tiveram valores similares. Os maiores índices de riqueza foram encontrados nos pontos próximos à floresta, enquanto menores valores foram observados nos pontos próximos ao mar. A maioria das sequências de RNAr 16S obtidas em Bertioga no meio do manguezal e próximo à floresta tiveram identidades menores do que 90% com as disponíveis no GenBank. Estas sequências podem representar novos táxons ou cianobactérias conhecidas, porém ainda não sequenciadas. O TRFLP do gene nifH indicou que os locais próximos ao mar e meio do manguezal na Ilha do Cardoso abrigaram populações de diazotróficos semelhantes, enquanto que em Bertioga estes pontos apresentaram diferenças nos perfis de TRFLP. As maiores diferenças estavam nos locais próximos à floresta em ambos os manguezais. / Microorganisms play important role in the recycling of elements in mangrove ecosystems, since as primary producers they can control chemical reactions. The particular cyanobacteria group act promoting the input of carbon and nitrogen through their ability to realize oxygenic photosynthesis and fixing atmospheric nitrogen. In Brazil, the mangrove forests occupy an area of approximately 25.000 km2, and in the total area of São Paulo State, 240 km2 are covered by this ecosystem. The aim of this work was to evaluate the cyanobacterial diversity that colonize Avicennia schaueriana, Rhizophora mangle and Laguncularia racemosa leaves from Cardoso Island mangrove, a pristine site, as well as to assess and compare the soil cyanobacterial population from both Cardoso Island and Bertioga mangroves, this last one contaminated with crude oil. For this purpose, the techniques of DGGE and clone library of 16S rRNA gene, ARISA, and TRFLP of nifH gene were used. The phyllosphere results evidenced a subtle difference of the genus of tree on the colonization of cyanobacteria, however a strong effect from trees location within the mangrove was observed. The tree leaves from the middle of mangrove area showed a greater diversity of cyanobacterial genera. In geral, 19 genera and several uncultivated cyanobacteria were identified. A predominance of sequences with high similarities to representatives of the order Nostocales and Oscillatoriales were observed. Sequences with similarities to the genus Symphyonemopsis (order Stigonematales) were recovered in higher quantity. Regarding to the soil diversity, DGGE and ARISA results showed that the cyanobacterial population is distinct among both mangroves studied, however the electrophoretic profiles from samples collected near to the sea grouped together, suggesting that colonization is influenced by flood conditions. The most different profile was obtained in the site near to the forest in Bertioga mangrove, location more affected by the oil contamination. Clone libraries clearly showed 16S rRNA sequences differences among sites sampled. A total of 99 OTUs were obtained, with 61 singletons. In the site near to the sea the Procholorococcus and Synechococcus genera were dominant in both mangroves. The majority of 16S rRNA sequences found in the other sites were related to uncultured cyanobacteria. Alpha diversity suggested that the site with lowest diversity was middle of the Bertioga mangrove, and the highest was Bertioga near to the forest, the remainder sites had similar values. The highest richness indices were found in the sites near to the forest, while lower values were observed in the sites near to the sea. The majority of the 16S rRNA sequences obtained from the middle of the mangrove and near to the forest in Bertioga showed identities lower than 90% with that available in the GenBank. These sequences may represent novel cyanobacterial taxa or known cyanobacteria not yet sequenced. The TRFLP of nifH gene indicated that the sites near to the sea and middle of the Cardoso Island mangrove harbored similar diazotrophic populations, while in Bertioga these sites presented differences in TRFLP profiles. The greatest differences were in the sites near to the forest in both mangroves.
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Acquisition de tolérance et modification de structure des communautés périphytiques : une réponse précoce à la pression urbaine dans les milieux aquatiquesFechner, Lise 14 December 2010 (has links) (PDF)
La contamination des milieux aquatiques urbains se caractérise aujourd'hui par un mélange de micropolluants d'origines et de types variés. Les conséquences de ce type de contamination, multiples mais faibles et chroniques, sur les écosystèmes aquatiques sont difficiles à évaluer. En effet, il est difficile d'une part de dresser un état des lieux précis de la contamination et d'autre part, de relier cette contamination à la réponse biologique des organismes exposés puisqu'elle n'engendre pas nécessairement des effets visibles et immédiats. Cette étude a pour objectif de développer une méthodologie permettant d'utiliser le périphyton pour évaluer l'impact d'une contamination urbaine typique. Les biofilms sont des communautés aquatiques complexes jouant un rôle primordial dans le fonctionnement des écosystèmes aquatiques. Leur réponse biologique à une perturbation peut s'évaluer au niveau structurel comme au niveau fonctionnel. Une première étape de ce travail a consisté à développer d'une part un test de toxicité aiguë permettant d'évaluer la tolérance de la composante hétérotrophe des biofilms selon le concept PICT, et d'autre part l'utilisation de la technique d'empreinte génétique ARISA pour évaluer des modifications de structure des communautés bactériennes et eucaryotes des biofilms. Les méthodologies développées ont ensuite été testées au laboratoire par des expositions de périphyton à des métaux à des concentrations environnementales. Par la suite, elles ont pu être déployées in situ : d'abord dans un gradient de contamination multi-métallique sur la Seine avec des prélèvements ponctuels de biofilms naturels ainsi qu'une expérience de transposition (amont/aval de l'agglomération parisienne). Enfin, le lien entre la tolérance du périphyton et la contamination métallique globale du milieu a été exploré à l'échelle d'un bassin versant. Les résultats sont prometteurs quant à l'utilisation du périphyton pour évaluer l'impact d'une contamination urbaine
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Maintenance of the Quality Monitor Web-ApplicationPonomarenko, Maksym January 2013 (has links)
Applied Research in System Analysis (ARiSA) is a company specialized in the development of the customer-specific quality models and applied research work. In order to improve the quality of the projects and to reduce maintenance costs, ARiSA developed Quality Monitor (QM) – a web application for quality analysis. QM application has been originally developed as a basic program to enable customers to evaluate the quality of the sources. Therefore, the business logic of the application was simplified and certain limitations were imposed on it, which in its turn leads to a number of issues related to user experience, performance and architecture design. These aspects are important for both application as a product, and for its future promotion. Moreover, this is important for customers, as end users. Main application issues, which were added to the maintenance list are: manual data upload, insufficient server resources to handle long-running and resource consuming operations, no background processing and status reporting, simplistic presentation of analysis results and known usability issues, weak integration between analysis back-ends and front-end. In order to address known issues and to make improvements of the existing limitations, a maintenance phase of QM application is initiated. First of all, it is intended to stabilize current version and improve user experience. It also needed for refactoring and implementation of more efficient data uploads processing in the background. In addition, extended functionality of QM would fulfill customer needs and transform application from the project into a product. Extended functionality includes: automated data upload from different build processes, new data visualizations, and improvement of the current functionality according to customer comments. Maintenance phase of QM application has been successfully completed and master thesis goals are met. Current version is more stable and more responsive from user experience perspective. Data processing is more efficient, and now it is implemented as background analysis with automatic data import. User interface has been updated with visualizations for client-side interaction and progress reporting. The solution has been evaluated and tested in close cooperation with QM application customers. This thesis describes requirements analysis, technology stack with choice rationale and implementation to show maintenance results.
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Molekularbiologische Analyse mikrobieller Gemeinschaften in TalsperrensedimentenBleul, Catrin 11 September 2004 (has links) (PDF)
Mikrobielle Prozesse spielen eine wichtige Rolle im Sediment von Talsperren und Seen. Demgegenüber stehen nur unzureichende Erkenntnisse über die Zusammensetzung mikrobieller Biozönosen in Sedimenten sowie deren Aktivität zur Verfügung. Das Ziel dieser Studie war die Untersuchung und der Vergleich der Zusammensetzung und der Struktur mikrobieller Gemeinschaften in Sedimenten um eine Abschätzung der mikrobiellen Diversität in Talsperrensedimenten unterschiedlicher Trophie zu erreichen. Durch die Kombination der in dieser Arbeit verwendeten Methoden (Vergleichende 16S rDNA Analyse, Fingerprinttechniken, klassische Methoden) konnte eine Charakterisierung der mikrobiellen Zusammensetzung der obersten 5 cm von den Talsperrensedimenten Neunzehnhain, Muldenberg, Quitzdorf und Saidenbach erzielt werden. Die vergleichende 16S rDNA Analyse offenbarte in 2541 analysierten rekombinanten Klonen 528 verschiedene Sequenztypen, welche zu 293 OTUs zusammengefaßt werden konnten. Obwohl die Gemeinschaften der verschiedenen Talsperren nur schwach auf der Ebene der phylogenetischen Gruppen differierten, konnte durch die Verwendung von Ähnlichkeitsindices gezeigt werden, dass jede Talsperre eine spezifische mikrobielle Sedimentgemeinschaft aufweist. Über 60% aller Klone zeigten Ähnlichkeiten von mehr als 97% zu 16S rDNA-Sequenzen kultivierter Organismen oder phylogenetisch eingeordneten Sequenzen (14 bekannte phylogenetische Gruppen). Alle anderen Klone zeigten hohe Sequenzhomologien zu unidentifizierten, phylogenetisch bisher nicht eingeordneten Bakterien. Diese Bakterien waren mit Anteilen zwischen 19,8% (Muldenberg) und 54,6% (Saidenbach) in den 16S rDNA Bibliotheken repräsentiert. Mittels Fingerprinttechniken (DGGE, T-RFLP, ARISA) konnten komplexe Muster der mikrobiellen Diversität erzeugt werden. Dabei konnten die Ergebnisse der 16S rDNA Analyse bestätigt werden. Durch die verwendeten Methoden konnte eine komplexe mikrobielle Diversität in den Sedimenten aufgedeckt werden und die Ergebnisse weisen darauf hin, dass die mikrobielle Diversität in Sedimenten wesentlich höher ist als bisher angenommen.
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Molekularbiologische Analyse mikrobieller Gemeinschaften in TalsperrensedimentenBleul, Catrin 13 September 2004 (has links)
Mikrobielle Prozesse spielen eine wichtige Rolle im Sediment von Talsperren und Seen. Demgegenüber stehen nur unzureichende Erkenntnisse über die Zusammensetzung mikrobieller Biozönosen in Sedimenten sowie deren Aktivität zur Verfügung. Das Ziel dieser Studie war die Untersuchung und der Vergleich der Zusammensetzung und der Struktur mikrobieller Gemeinschaften in Sedimenten um eine Abschätzung der mikrobiellen Diversität in Talsperrensedimenten unterschiedlicher Trophie zu erreichen. Durch die Kombination der in dieser Arbeit verwendeten Methoden (Vergleichende 16S rDNA Analyse, Fingerprinttechniken, klassische Methoden) konnte eine Charakterisierung der mikrobiellen Zusammensetzung der obersten 5 cm von den Talsperrensedimenten Neunzehnhain, Muldenberg, Quitzdorf und Saidenbach erzielt werden. Die vergleichende 16S rDNA Analyse offenbarte in 2541 analysierten rekombinanten Klonen 528 verschiedene Sequenztypen, welche zu 293 OTUs zusammengefaßt werden konnten. Obwohl die Gemeinschaften der verschiedenen Talsperren nur schwach auf der Ebene der phylogenetischen Gruppen differierten, konnte durch die Verwendung von Ähnlichkeitsindices gezeigt werden, dass jede Talsperre eine spezifische mikrobielle Sedimentgemeinschaft aufweist. Über 60% aller Klone zeigten Ähnlichkeiten von mehr als 97% zu 16S rDNA-Sequenzen kultivierter Organismen oder phylogenetisch eingeordneten Sequenzen (14 bekannte phylogenetische Gruppen). Alle anderen Klone zeigten hohe Sequenzhomologien zu unidentifizierten, phylogenetisch bisher nicht eingeordneten Bakterien. Diese Bakterien waren mit Anteilen zwischen 19,8% (Muldenberg) und 54,6% (Saidenbach) in den 16S rDNA Bibliotheken repräsentiert. Mittels Fingerprinttechniken (DGGE, T-RFLP, ARISA) konnten komplexe Muster der mikrobiellen Diversität erzeugt werden. Dabei konnten die Ergebnisse der 16S rDNA Analyse bestätigt werden. Durch die verwendeten Methoden konnte eine komplexe mikrobielle Diversität in den Sedimenten aufgedeckt werden und die Ergebnisse weisen darauf hin, dass die mikrobielle Diversität in Sedimenten wesentlich höher ist als bisher angenommen.
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