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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
551

Varia??o espacial e sazonal de elementos maiores e tra?os no estu?rios do Rio Curimata? (RN), atrav?s de dados geoqu?micos e de sensoriamento remoto

Garlipp, Adriana Baggio 27 October 2006 (has links)
Made available in DSpace on 2015-02-24T19:48:45Z (GMT). No. of bitstreams: 1 AdrianaBG_capa_ate_secao5.pdf: 3230514 bytes, checksum: e499db1cdb9c0ab6b161220ff77e224a (MD5) Previous issue date: 2006-10-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The Curimata? estuary is located in the oriental coast of Rio Grande do Norte State in Brazil. Its importance resides in the fact that this region possesses one of the last portions of preserved mangrove in the Rio Grande do Norte State. Nevertheless, it has been severely affected by many anthropogenic activities, as sugarcane monoculture and shrimp farming. Former works demonstrated that an accumulation of heavy metals is occurring in oysters in this estuary, and perhaps it could be explained by the input of metals in this ecosystem deriving from the shrimp farming. To better understanding the origin of these metals, bottom sediment samples, cores and suspended particulate matter were collected for a characterization of metal concentrations (Al, Ba, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Zn) and to determine the potentially bioavailable metals. Additionally, the enrichment ratio for each element analyzed was calculated. The mineralogical composition of sediment samples and cores were obtained by X-ray diffraction. Moreover, data of orbital remote sensing were used in order to detect and quantify suspended matter by applying a logarithmic algorithm. Geochemical data of bottom sediments and cores revealed that, excepting Ba and Pb, the elements analyzed presented concentrations characteristic of an unpolluted ecosystem (Al: 0,25 - 8,76 %; Ba: 3,03 - 870 ?g.g-1; Cd: < 0,25 ?g.g-1; Cr: 1,72 - 82,4 ?g.g-1; Cu: 0,12 -25,3 ?g.g-1; Pb: 0,38 - 23,7 ?g.g-1; Fe: 0,10 - 5,82 %; Mn: 15,1 - 815 ?g.g-1; Ni: 0,14 - 36,1 ?g.g-1; Zn: 1,37 - 113 ?g.g-1). During the dry season a distribution pattern was observed, with higher metal concentrations in the margins, decreasing toward the central portion of the channel. These metal concentrations were well correlated with mineralogical compositions, with clay minerals prevailing at the margins, and quartz and feldspar in the center. However, this pattern was not observed during the wet season, probably because of the high water flux that disturbed bottom sediments. But, as observed for the dry season, a good correlation between metal concentrations and mineralogical composition was also observed for the wet season, with high metal concentrations where there were high quantities of clay minerals. Low enrichment ratios were obtained for the majority of elements analyzed, excepting for Mn, Ba and Pb. Manganese presented the higher ratios downstream for both seasons, and it can be an evidence of anthropogenic impact by shrimp farming. As barium and lead concentrations in sediment samples presented analytical problems during the total sample digestion, one cannot be sure that the ratios obtained correspond to the reality. The highest metal concentrations in particulate matter were obtained in the portion dominated by fluvial transport for all metals analyzed, excepting for copper. Barium and zinc were the only elements that presented elevated concentrations that are not common of unpolluted ecosystems (Ba: 5730 - 8355 ?g.g-1; Zn: 3899 - 4348 ?g.g-1). However, these high concentrations could not be related to the shrimp farming and waste waters from the town of Canguaretama, once they were obtained from the fluvial particulate matter, that is upstream from the activities above mentioned. The application of the logarithmic algorithm to the processed LANDSAT image was well succeeded, although the acquired image does not correspond exactly to the field campaigns. The IKONOS image provided very detailed views of the suspended sediment concentration at the estuary, as the mixture of distinct water flows at the confluence of Cunha? and Curimata? rivers, with more turbid waters from Cunha? river, that is directly affected by effluents from shrimp farming and urban waste waters deriving from the town of Canguaretama / O estu?rio do rio Curimata? localiza-se na por??o sul do litoral oriental do Estado do Rio Grande do Norte, apresentando uma das ?ltimas por??es de manguezais no Estado. Este ecossistema tem sido fortemente afetado por diversas atividades antropog?nicas, como o cultivo de cana-de-a??car, a carcinicultura, al?m da urbaniza??o. Trabalhos anteriores neste local revelaram que ostras Crassostrea rhizophorae apresentaram concentra??es de alguns metais acima dos limites permitidos para consumo, e que talvez a entrada destes metais no estu?rio estivesse relacionada aos efluentes de carcinicultura. Para uma melhor compreens?o da origem destes metais, foram coletadas amostras de sedimento de fundo, testemunhos e material particulado em suspens?o para uma caracteriza??o das concentra??es de dez elementos maiores e tra?os (Al, Ba, Cd, Cu, Cr, Fe, Mn, Ni, Pb, Zn), bem como para a determina??o dos elementos potencialmente biodispon?veis. Al?m disso, tamb?m foi realizado o c?lculo da raz?o de enriquecimento para cada elemento analisado. A composi??o mineral?gica das amostras de sedimento de fundo e dos testemunhos foi obtida atrav?s de difratometria de raios-X. Adicionalmente, dados de sensoriamento remoto orbital foram usados a fim de se detectar e semiquantificar o material particulado em suspens?o atrav?s da aplica??o de um algoritmo logar?tmico. As an?lises geoqu?micas das amostras de sedimento de fundo revelaram que os elementos analisados apresentaram concentra??es caracter?sticas de um estu?rio n?o polu?do (Al: 0,25 a 8,76%; Ba: 3,03 a 870 ?g.g-1; Cd: < 0,25 ?g.g-1; Cr: 1,72 a 82,4 ?g.g-1; Cu: 0,12 a 25,3 ?g.g-1; Pb: 0,38 a 23,7 ?g.g-1; Fe: 0,10 a 5,82 %; Mn: 15,1 a 815 ?g.g-1; Ni: 0,14 a 36,1 ?g.g-1; Zn: 1,37 a 113 ?g.g-1). Um padr?o de distribui??o dos metais foi observado durante a esta??o seca, com maiores concentra??es nas margens, diminuindo em dire??o ao centro do canal. A concentra??o dos metais se mostrou bem correlacionada com as respectivas composi??es mineral?gicas das amostras de sedimento, com minerais de argila predominando nas margens, e quartzo e feldspato mais presentes no centro do canal. Contudo, este padr?o n?o foi observado durante a esta??o chuvosa, provavelmente devido ao fluxo de ?gua mais intenso que promoveu o dist?rbio dos sedimentos de fundo, com remo??o da fra??o fina das margens. Mas, da mesma forma que observado para a esta??o seca, nas amostras coletadas durante a esta??o chuvosa tamb?m se observou maiores concentra??es de metais nas amostras com predom?nio de minerais argilosos. Raz?es de enriquecimento sugestivas de aus?ncia de polui??o foram obtidas para a maioria dos elementos analisados, com exce??o de Mn. O mangan?s apresentou as maiores raz?es ? jusante da atividade de carcinicultura, as quais sugerem polui??o significativa neste trecho durante ambas as esta??es seca e chuvosa. Esta pode ser uma evid?ncia do impacto da carcinicultura no estu?rio, j? que a montante desta atividade a raz?o de enriquecimento foi baixa. No material particulado em suspens?o as maiores concentra??es de metais foram obtidas na por??o dominada pelo transporte fluvial para todos os elementos analisados, com exce??o do cobre. Os ?nicos elementos que apresentaram concentra??es elevadas, incomuns para ambientes livres de polui??o, foram b?rio (de 5730 a 8355 ?g.g-1) e zinco (de 3899 a 4348 ?g.g-1). Contudo, estas concentra??es anormais aparentam n?o estar relacionadas ? carcinicultura ou aos efluentes da cidade de Canguaretama, uma vez que foram encontrados ? montante destas atividades. A aplica??o do algoritmo logar?tmico ? imagem LANDSAT foi bem sucedida, embora a imagem adquirida n?o corresponda exatamente ?s datas de coleta do material em suspens?o. A imagem IKONOS forneceu vis?es muito detalhadas do estu?rio que permitiram observar a distribui??o do material particulado, com a mistura de fluxos de ?gua distintos na conflu?ncia dos rios Cunha? e Curimata?, sendo que o rio Cunha? apresenta ?guas mais turvas, e ? diretamente afetado pelos efluentes de carcinicultura e dejetos urbanos da cidade de Canguaretama
552

Diagn?stico geoambiental com uso do geoprocessamento visando a determina??o de potencialidades de uso do solo para a ?rea estuarina do Rio Curimata? - Canguaretama(RN)

Fernandes, Rodrigo Cysneiros 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T15:19:59Z (GMT). No. of bitstreams: 1 RodrigoCF.pdf: 3320677 bytes, checksum: 8e14c54d294c2ecf5424b620562449ae (MD5) Previous issue date: 2006-05-19 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The activities developed in the coastal zone always arise the researchers interest, mainly when it is developed in fragile ecological areas, not observing the sustenable development laws. In this context, the analysis presented developed around the estuary of Curimatau river, located in the Eastern coast of Rio Grande do Norte state, integrates information provided by high resolution images of orbital remote sensing (IKONOS II, dated of July of 2003) and images of not-orbital remote sensing (Air photographs of DPU, dated of March of 1997) in a multitemporary perspective, diagnosising patterns of use and occupation, evaluating the main area?s impacts, together with the estuarian region fisiograph of Curimatau river. The use of high resolution images consequently allowed generates a precision cartography, facilitating the quantification of the evolution of the landscape and supporting decisions. Was possible yet, the definition of use areas, conservation areas and preservation areas; that were inserted in the concept of Potentialities: a fundamental element to management of vulnerable areas of the natural point of view. The information provided during the research had been stored in an Enviromental Georreferenced Data Base, constructed under the optics of Geographical Information Systems (GIS), that they facilitate the environment management Through fast access to information. The results were satisfactory, because permits the quantification of evolution of the landscape and the mapping. Beyond the geoenviromental diagnosis, was possible develop maps and matrixes that support the Rio Grande do Norte state costal Management. / As atividades desenvolvidas na zona costeira sempre despertaram o interesse dos pesquisadores, principalmente quando s?o desenvolvidas em ?reas ecologicamente fr?geis, n?o observando os preceitos do desenvolvimento sustentavelmente empreendido. Nesse contexto, a an?lise apresentada neste trabalho, desenvolvido no entorno do estu?rio do rio Curimata?, localizado no litoral Oriental do estado do Rio Grande do Norte, integra informa??es obtidas atrav?s de imagens de alta resolu??o de sensoriamento remoto orbital (IKONOS II, datadas de julho de 2003) e imagens de sensoriamento remoto n?o-orbital (Fotografias A?reas da DPU, datadas de mar?o de 1997) numa perspectiva multitemporal, diagnosticando os padr?es de uso e ocupa??o, avaliando os principais impactos da ?rea, juntamente com a fisiografia da regi?o estuarina do rio Curimata?. A utiliza??o de imagens de alta resolu??o permitiu a gera??o de uma cartografia de precis?o, facilitando a quantifica??o da evolu??o da paisagem e conseq?entemente a tomada de decis?es. Permitiram, ainda, a defini??o de ?reas de uso, ?reas de conserva??o e ?reas de preserva??o; par?metros, estes, inseridos no conceito de Potencialidades; altamente v?lido na gest?o de ?reas vulner?veis do ponto de vista natural. As informa??es obtidas no decorrer da pesquisa foram armazenadas em um Banco de Dados Ambientais Georreferenciados, constru?do sob a ?tica dos Sistemas de Informa??es Geogr?ficas (SIG?s), que facilitam sobremaneira a gest?o ambiental, no sentido de as informa??es poderem ser acessadas de forma r?pida e racional. Os resultados foram bastante satisfat?rios, pois permitiram a quantifica??o da evolu??o da paisagem e o mapeamento preciso das fei??es ocorrentes na ?rea de estudo, tendo sido poss?vel gerar, al?m do diagn?stico geoambiental, matrizes e mapas que auxiliar?o de maneira racional, simples, r?pida e barata o gerenciamento costeiro do estado do Rio Grande do Norte.
553

A Study on the Integration of Multivariate MetOcean, Ocean Circulation, and Trajectory Modeling Data with Static Geographic Information Systems for Better Marine Resources Management and Protection During Coastal Oil Spill Response – A Case Study and Gap Analysis on Northeastern Gulf of Mexico Tidal Inlets

Knudsen, Richard Ray 06 November 2015 (has links)
The Oil Pollution Act of 1990 requires the development of Regional and Area Contingency Plans. For more than 20 years, the State of Florida, under both the Department of Environmental Protection and the Florida Fish and Wildlife Commission, has worked closely with the U.S. Coast Guard and the National Oceanic and Atmospheric Administration to develop these plans for coastal and marine oil spill response. Current plans, developed with local, state and federal stakeholder input, use geographic information systems (GIS) data such as location and extent of sensitive ecological, wildlife, and human-use features (termed Environmental Sensitivity Index data), pre-defined protection priorities, and spatially explicit protection strategies to support decision-making by responders (termed Geographic Response Plans). However, they are long overdue for improvements that incorporate modern oceanographic modeling techniques and integrated data from coastal ocean observing systems. Better understanding of circulation in nearshore and estuarine waters, at a scale consistent with other spatial data, is especially lacking in Area Contingency Plans. This paper identifies the gaps in readily available information on the circulation-driven causes and effects missing in current oil spill contingency planning and describes a sample methodology whereby multiple coastal and ocean spatial science disciplines are used to answer questions that no single, non-integrated discipline can answer by itself. A path forward for further integration and development of more comprehensive plans to better support coastal protection in Florida is proposed. The advances made here are applicable to other coastal regions of the world.
554

Estrutura atual da pesca artesanal e estimativa do autoconsumo de pescado entre pescadores artesanais do estuário da Lagoa dos Patos, RS, Brasil

Lima, Bruna Barros January 2012 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2012. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-11-18T16:09:12Z No. of bitstreams: 1 BRNA.pdf: 776201 bytes, checksum: 2dd5a6dcf1118a798cbd5a740899215e (MD5) / Approved for entry into archive by Angelica Miranda (angelicacdm@gmail.com) on 2013-11-18T19:39:01Z (GMT) No. of bitstreams: 1 BRNA.pdf: 776201 bytes, checksum: 2dd5a6dcf1118a798cbd5a740899215e (MD5) / Made available in DSpace on 2013-11-18T19:39:01Z (GMT). No. of bitstreams: 1 BRNA.pdf: 776201 bytes, checksum: 2dd5a6dcf1118a798cbd5a740899215e (MD5) Previous issue date: 2012 / O presente trabalho é dividido em dois capítulos, os quais apresentam estudos realizados em três comunidades de pescadores do estuário da Lagoa dos Patos: a São Miguel, o Bosque e a Torotama. O primeiro capítulo trata da estrutura da frota da pesca artesanal na região e sua evolução ao longo do tempo. Foram entrevistados 20 pescadores de cada comunidade, que responderam perguntas com relação aos seus petrechos de pesca e sua visão com relação a mudanças ocorridas no setor. Observou-se uma tendência à diminuição do tamanho de malha das redes, assim como o aumento da potência dos motores, o que evidencia um aumento de esforço pesqueiro quando comparado a décadas passadas. Os pescadores têm consciência das alterações que a pescaria vem sofrendo. O segundo capítulo aborda um assunto pouco estudado no Brasil, o autoconsumo dos pescadores artesanais, ou seja, a quantidade e o tipo de pescado consumido pelos pescadores e seus familiares daquilo que é capturado por eles próprios. Foram entrevistados periodicamente 10 pescadores de cada comunidade, de setembro de 2010 a dezembro de 2011. Coletaram-se informações pessoais sobre a atividade pesqueira e autoconsumo de pescado. O consumo médio anual por pessoa foi de 38,57 kg. A primavera e o verão foram as estações de maior consumo, sendo a corvina e o camarão-rosa as espécies mais consumidas nessas estações, respectivamente. / This study is divided into two chapters which presents studies done in three fishing communities of Patos Lagoon’s estuary: São Miguel, Bosque and Torotama. The first chapter is about the artisanal fishery’s fleet structure in the region and its evolution in time. Twenty fishermen of each community were interviewed, they answered questions about their vessels and the fishing gears and their vision about the changes that occurred in the sector. It was observed reduction trend in mesh sizes as well an increase of the engine power indicating an increase of fishing effort. Fishermen are aware of the changes the fishery has being undergoing. The second chapter addresses a less investigated issue in Brazil, the artisanal fishery self-consumption, i.e., the amount and type of fish consumed by the fishermen and their family of what is captured by them. Ten fishermen of each community were periodically interviewed, from September 2010 to May 2011. Personal information about the fishing activity and fish selfconsumption was collected. The average annual consumption per person was of 38.57 kg. Higher consumption occurred in spring and summer, the white croaker and the pink shrimp are the most consumed species in these seasons, respectively.
555

Resposta metabólica aeróbia, anaeróbia e argininolítica do bagre Genidens Genidens, (Curvier, 1829), presentes nos estuários do município de Ubatuba / Aerobic, anaerobic and argininolitic metabolic response of the catfish Genidens genidens (Cuvier, 1829), present in esturaries of the municipality of Ubatuba

Rosangela Almeida Victor 27 March 2009 (has links)
A resposta metabólica do bagre Genidens genidens de três estuários (rios Grande, Indaiá e Escuro) do município de Ubatuba SP foi estudada comparativamente em relação ao impacto da atividade humana na região. Encéfalo, fígado e músculo epaxial foram utilizados para determinar a atividade específica das enzimas lactato desidrogenase (LDH), malato desidrogenase (MDH) e arginase, como prováveis marcadoras desse impacto. As diferenças entre os níveis teciduais de LDH dos bagres coletados nos três estuários não foram significativamente diferentes, provavelmente devido a sua capacidade adaptativa, associada à sazonalidade das concentrações de oxigênio nas águas estuarinas. Os níveis de arginase hepática e muscular dos bagres coletados nos estuários dos rios Escuro e Indaiá, respectivamente, foram diferentes em relação aos dois outros estuários. Comportamento semelhante a esse foi constatado em relação aos níveis da enzima MDH, marcadora do potencial gerador de ATP desses tecidos. Nesse sentido, os níveis de arginase e MDH do fígado e músculo epaxial podem estar refletindo o esforço adaptativo metabólico desse bagre às condições ambientais dessas regiões estuarinas. / The metabolic response of catfish Genidens genidens of the three estuaries (Grande, Indaia and Escuro rivers) in the municipality of Ubatuba - SP was studied in comparison to the impact of human activity in the region. Brain, liver and epaxial muscle were used to determine the specific activity of the enzymes lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and arginase, as probable markers of that impact. The differences between the tissues levels of LDH of the catfishes collected in the three estuaries were not significantly different, probably due to its adaptive capacity, associated with the seasonality of the oxygen concentrations in estuarine waters. Arginase levels of liver and muscle of the catfishes collected in estuaries of rivers Escuro and Indaia, respectively, were different in the relation to the other two estuaries. Behavior was similar to that observed in the levels of the enzyme MDH, marker of the potential generator of ATP of those tissues. Accordingly, the levels of arginase and MDH of the liver and epaxial muscle might reflect the effort of that adaptive metabolic catfish to environmental conditions such estuarine areas.
556

Contribuição à exploração tecnológica dos estudos microbianos realizados no programa BIOTA FAPESP: avaliação do potencial da degradação anaeróbia de pentaclorofenol (PCP) em reator anaeróbio horizontal de leito fixo (RAHLF) / Contribution to technological research of the microbial studies done at program BIOTA FAPESP: evaluation of anaerobic Pentachlorophenol (PCP) biodegradation in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor

Flávia Talarico Saia 01 July 2005 (has links)
O estudo que ora se apresenta integrou o conjunto de pesquisas do sub-projeto - Diversidade de Bactérias Associadas à Degradação de Compostos Recalcitrantes, do projeto temático BIOTA FAPESP - Ecologia Molecular e Taxonomia Polifásica de Bactérias de Interesse Ambiental e Agro-Industrial. Apresenta caráter inovador, na medida em que procurou avaliar o potencial de aplicação biotecnológica de microrganismos anaeróbios de uma área severamente contaminada no Brasil, o estuário de Santos-São Vicente, em degradar o pentaclorofenol (PCP). A pergunta fundamental a ser respondida pelos resultados experimentais realizados foi: são os microrganismos autóctones do estuário capazes de servirem de inóculo para degradar o pentaclorofenol em biorreatores sob condições metanogênicas? Dois grupos de amostras foram avaliados, o primeiro, uma parcela composta por vários sedimentos coletados no estuário e, o segundo, sedimentos coletados na região do Largo de Canéus e na frente da Companhia Siderúrgica Paulista (COSIPA). O estabelecimento da determinação cromatográfica do PCP e congêneres menos clorados para o monitoramento experimental mostrou que na análise da presença dos clorofenóis nos sedimentos, o método de extração por ultrassom com posterior metilação dos analitos foi adequado para concentração mínima de 200 'mü'g clorofenóis/Kg sedimento para 2,3; 2,6 diclorofenóis; 2,4,6 e 2,3,6 triclorofenóis. Contudo, não foi adequado para a determinação do PCP e 2,3,4 triclorofenol. Para o meio de cultivo, o método de extração do PCP por agitação em vórtex e acetilação dos analitos mostrou-se adequado para todos os clorofenóis e com limite de quantificação de 0,1 mg/L. A avaliação do potencial metanogênico foi realizada com as amostras compostas do estuário enriquecidas sob condições halofílicas. O valor estável de metano no biogás de 50% foi obtido nos primeiros 20 dias de incubação. O sedimento nessas condições foi utilizado como inóculo para fins de isolamento de culturas metanogênicas, redutoras do íon sulfato e degradadoras de PCP. Não foram obtidas culturas desalogenadoras; porém foram isoladas arquéias metanogênicas, cultivadas em metanol, acetato e formiato de sódio, bem como bactérias cultivadas em lactato de sódio na presença e ausência de sulfato de sódio. Ensaios fisiológicos aliados aos métodos moleculares FISH e DGGE permitiram identificar arquéias metanogênicas do gênero Methanosarcina sp. e microrganismos do domínio Bacteria. Os sedimentos individualmente estudados foram coletados com maior controle de anaerobiose empregando-se amostrador do tipo corer. O enriquecimento destes sedimentos, inicialmente sob concentração de 2,5 mg PCP/g STV e com adições periódicas de 50% da concentração inicial do clorofenol e 1,25 a 2,5 g/L de glicose por 13 meses a 30 graus Celsius, resultou na obtenção de culturas degradadoras do PCP sob anaerobiose estrita. Nos reatores controles sem PCP, já primeiros 20 dias de incubação 70% de metano foi determinado no biogás. Nos reatores com PCP, a produção do metano (20%) iniciou após 100 dias. A adsorção foi o principal mecanismo de remoção de 50% do PCP nas primeiras 12 horas de incubação dos enriquecimentos. Posteriormente, a redução do PCP no meio de 77% para a amostra de Canéus e 70% para a da COSIPA foi relacionada a mecanismos de biodegradação anaeróbia, como a desalogenação redutiva. Exames microscópicos mostraram a seleção de microrganismos na presença de PCP, com predomínio de bacilos formadores de esporos semelhantes ao gênero Clostridium sp., filamentos diversos e filamentos semelhantes as arquéias metanogênicas acetoclásticas relacionadas ao gênero Methanosaeta sp. O enriquecimento foi realizado sob condições halofílicas, segunda a salinidade de cada amostra estudada no estuário. Não houve perda do clorofenol por volatilização. Os resultados obtidos no enriquecimento anterior viabilizaram o estudo seguro do potencial anaeróbio dos microrganismos oriundos do sedimento da COSIPA em metabolizar o PCP em reator contínuo do tipo RAHLF. Assim, sedimento enriquecido sob condições metanogênicas e halofílicas foi inoculado no RAHLF, controlando-se rigorosamente a anaerobiose. O reator preenchido com cubos de espuma de poliuretana foi operado por 126 dias e tempo de detenção hidráulica de 18 horas, com meio de cultura salino contendo glicose (1 g/L) como principal fonte de carbono e PCP-Na nas concentrações de 5, 13, 15 e 21 mg/L. O desempenho do RAHLF foi estável com boa eficiência durante toda a operação. A redução dos níveis de matéria orgânica medida em DQO variou de 70 a 100% e a de PCP foi de 99%, com detecção de intermediários menos clorados e sob teores de metano no biogás de 20%. Da massa de 1111,73 mg de PCP aplicada no reator, 286,9 mg ficou retida no sistema pelo processo de adsorção nas biopartículas e 824,83 mg foi biodegradada. As análises morfológicas dos tipos celulares, em conjunto com as técnicas moleculares DGGE e FISH, revelaram a presença de grupos microbianos do domínio Archaea pertencente à família Methanosarcinacea e grupos do domínio Bacteria. A participação de grupos de domínio Bacteria, cuja estrutura dos tipos microbianos na comunidade variou ao longo do RAHLF e das concentrações de PCP, e dos organismos metanogênicos da família Methanosarcinacea, possibilitou responder a questão inicialmente formulada, uma vez que se pode afirmar que os microrganismos autóctones foram capazes de degradar o PCP sob condições metanogênicas e halofílicas, com eficiência adequada. A prática para a seleção dos microrganismos retirados do ambiente estuarino, de interesse para biotecnologia anaeróbia aplicada ao saneamento ambiental, que empregou o reator do tipo RAHLF, parece promissora para avanços da engenharia na remediação biológica de uma área cuja relevância é indiscutível para o estado de São Paulo / This study has an innovative character, once aimed to evaluate the biotechnological application of anaerobic microorganisms degrading pentachlorophenol (PCP) at a severely polluted area in Brazil, estuary of Santos-São Vicente, São Paulo state. This study integrated a group of researches of the sub-project - Diversity of Bacteria Associated to the Degradation of Recalcitrant Compounds, supported by major project BIOTA FAPESP which theme is Molecular Ecology and Polyphasic Taxonomy of Bacteria of Environmental and Agriculture-Industrial Interest. The fundamental question to be answered by the accomplished experimental results was: are the autochthonus microorganisms of the estuary capable of serving as inoculum to degrade the PCP in bioreactors under methanogenic conditions? In order to evaluate this hypothesis, two groups of samples were collected: sediments taken from several sites of the estuary and sediments taken from two sites, one severely contaminated with organochlorine compounds, in front of the São Paulo Metallurgical Company (COSIPA) and other, less contaminated, in the area of Canéus. The establishment of protocol for the PCP and less chlorinated compounds chromatographic determination showed that the extraction method by ultrosonication followed by metilation of the chlorinated compounds was appropriated to evaluate concentrations of 200 ug chlorophenol/Kg of sediment, 2,3; 2,6 dichlorophenols; 2,4,6 and 2,3,6 trichlorophenols. However, it was not appropriated for evaluation of PCP and 2,3,4 trichlorophenol. For the culture medium, the extraction method by vortex agitation followed by acetilation was appropriated for all of the chlorophenols compounds. The quantification limit was 0,1 mg/L. The evaluation of the methanogenic potential and PCP biodegradation was accomplished with the samples of the estuary enriched under halophylic conditions. In the experiments without PCP was possible to obtain cultures of Methanosarcina sp, identified by FISH technique and cells of domain Bacteria, identified by DGGE. In the experiment with PCP dehalogenated cultures were not obtained. To evaluate PCP anaerobic biodegradation by sediments of COSIPA and Caneus sites, sediments collected under anaerobic conditions by a corer device were enriched in a halophylic brine medium with glucose and PCP at concentration of 2.5 mg PCP/g VTS. Periodic additions of 50% of the initial concentration of PCP and 1.25 to 2.5 g/L of glucose were done. With this strategy was possible to obtain PCP dehalogenated cultures. The adsorption was the main mechanism of 50% of PCP removal in the first 12 hours of incubation. The PCP reduction of 77% for Caneus reactor and 70% for COSIPA reactor was related to anaerobic biodegradation. Microscopic exams showed selection of microorganisms, with predominance of cells related to Clostridium sp., and filaments related to methanogenic acetoclastic archaea Methanosaeta sp. chlorophenols volatilization was not observed. The biotechnological application of HAIB reactor in PCP biodegradation was evaluated using sediment of COSIPA site previously enriched with glucose. The reactor was operated by 126 days and hydraulic detention time of 18 hours, with saline brine medium containing glucose (1 g/L) and NaPCP in concentrations of 5, 13, 15 and 21 mg/L. PCP amendments did not affect the overall performance and functional stability of the process. COD and PCP reduction was close to 80% and 100%, respectively with detection of trichlorophenols and dichlorophenols. Percentage of methane in the biogas closed to 30%. Adsorption analyses demonstrated that 287 mg of PCP was removed by adsorption in the biofilm and 825 mg was removed by biodegradation. Biofilm DGGE-profiling showed the presence of specific bands of Bacteria and Archaea domains when PCP was amended. The appearance of new bands of Bacteria showed that this organisms had a direct influence at PCP dehalogentation. Archaea organisms of Methanosarcinaceae family had an indirect influence in this metabolism. This thesis demonstrated that HAIB reactors, using autochthonous microorganisms under halophylic and methanogenic conditions, are a potential alternative for organochlorines bioremediation
557

Habitat and Seasonal Distribution of the North American River Otter (Lontra canadensis) and Vertebrate Species Assemblages in Two Protected Areas of the Florida Everglades

Hamilton, Catherine Faye 01 November 2014 (has links)
The Florida Everglades ecosystem is threatened by human development, increased pollution, freshwater scarcity, and invasive species; factors that have negatively impacted the Everglades and native species health and populations. Man-made canals and levies have redirected the natural flow of fresh water from Lake Okeechobee into the Florida Everglades, starving central and south Florida ecosystems of necessary fresh water and nutrients. Through the efforts of the Comprehensive Everglades Restoration Project (CERP), freshwater is being redirected back into central and south Florida, returning the sheet flow of water back into the Everglades. Monitoring species abundance in the Everglades is a beneficial conservational tool for assessing restoration efforts from CERP. As a semi-aquatic apex predator, river otters (Lontra canadensis) are a useful health bio-indicator for the Florida Everglades. In order to conduct future population studies of river otters in the Florida Everglades, it must first be ascertained where they can be found and what time of year they are most likely to be sighted. For this study, Moultrie infrared game cameras were used to photograph the presence or absence of river otters within the five main habitats in the Everglades; the pinelands, hardwood hammock, cypress swamp, marsh prairie, and mangrove estuary at two protected areas in the Florida Everglades (Big Cypress National Preserve and Fakahatchee Strand State Park). River otters were most frequently sighted in the hardwood hammock habitat, but were also found in the cypress swamp. The large majority of river otter sightings occurred during dry season, which is thought to be a function of restricted water availability and aquatic mobility. Future population studies of river otters would be most productive in the hardwood hammock and cypress swamp habitats during dry season. Game camera images along with field opportunistic sightings, resulted in a variety of species documented. This provided valuable information of species richness and distribution within and amongst the habitats. The hardwood hammock was found to be the most species rich habitat, having over half the species observed in the study in this habitat. The Aves class was the most abundantly observed in the Everglades, and was most frequently sighted during the dry season. As a refuge for migratory birds, the Everglades house the majority of bird species during the winter months, which occur during dry season. The Aves class was most frequently sighted in the pinelands habitat during dry season. This habitat, being the highest in elevation and therefore the driest, shows a stronger resemblance to most northern bird habitats then does the water-saturated wetlands found throughout the Everglades. The mangrove estuary was the most commonly occurring outlier, having the least species overlap when compared to the other habitats. All other habitats in the Everglades are freshwater wetlands, while the mangrove estuary is a brackish environment, which limits the species that are unable to tolerate saline conditions. Further studies of species abundance throughout the Everglades will aid in monitoring CERP restoration efforts over time.
558

Bacterioplankton in the Baltic Sea : influence of allochthonous organic matter and salinity

Figueroa, Daniela January 2016 (has links)
Climate change is expected to increase the precipitation ~30% in higher latitudes during the next century, increasing the land runoff via rivers to aquatic ecosystems. The Baltic Sea will receive higher river discharges, accompanied by larger input of allochthonous dissolved organic matter (DOM) from terrestrial ecosystems. The salinity will decrease due to freshwater dilution. The allochthonous DOM constitute a potential growth substrate for microscopic bacterioplankton and phytoplankton, which together make up the basal trophic level in the sea. The aim of my thesis is to elucidate the bacterial processing of allochthonous DOM and to evaluate possible consequences of increased runoff on the basal level of the food web in the Baltic Sea. I performed field studies, microcosm experiments and a theoretical modeling study. Results from the field studies showed that allochthonous DOM input via river load promotes the heterotrophic bacterial production and influences the bacterial community composition in the northern Baltic Sea. In a northerly estuary ~60% of bacterial production was estimated to be sustained by terrestrial sources, and allochthonous DOM was a strong structuring factor for the bacterial community composition. Network analysis showed that during spring the diversity and the interactions between the bacteria were relatively low, while later during summer other environmental factors regulate the community, allowing a higher diversity and more interactions between different bacterial groups. The influence of the river inflow on the bacterial community allowed “generalists” bacteria to be more abundant than “specialists” bacteria.    Results from a transplantation experiment, where bacteria were transplanted from the northern Baltic Sea to the seawater from the southern Baltic Sea and vice versa, showed that salinity, as well as the DOM composition affect the bacterial community composition and their enzymatic activity. The results showed that α-proteobacteria in general were favoured by high salinity, β-proteobacteria by low salinity and terrestrial DOM compounds and γ-proteobacteria by the enclosure itself. However, effects on the community composition and enzymatic activity were not consistent when the bacterial community was retransplanted, indicating a functional redundancy of the bacterial communities.  Results of ecosystem modeling showed that climate change is likely to have quite different effect on the north and the south of the Baltic Sea. In the south, higher temperature and internal nutrient load will increase the cyanobacterial blooms and expand the anoxic or suboxic areas. In the north, climate induced increase in riverine inputs of allochthonous DOM is likely to promote bacterioplankton production, while phytoplankton primary production will be hampered due to increased light attenuation in the water. This, in turn, can decrease the production at higher trophic levels, since bacteria-based food webs in general are less efficient than food webs based on phytoplankton. However, complex environmental influences on the bacterial community structure and the large redundancy of metabolic functions limit the possibility of predicting how the bacterial community composition will change under climate change disturbances.
559

Dynamique sédimentaire et évolution holocène d'un système macrotidal semi-fermé : l'exemple de la rade de Brest / Sediment dynamics and Holocene evolution of a semi-closed macrotidal system : the example of the bay of Brest

Gregoire, Gwendoline 08 December 2016 (has links)
La rade de Brest constitue un cadre idéal pour étudier et restituer les transferts sédimentaires terre-mer dans un contexte de bassin côtier semi-fermé macrotidal. Dans cette perspective, deux axes majeurs, d’échelle temporelle différente, ont été développés avec pour objectifs (a) de caractériser le modèle sédimentaire et sa dynamique par charriage à l’actuelle, (b) de déterminer la mise en place des dépôts sédimentaires au cours de la dernière transgression marine.(a) L’analyse combinant une approche sédimentaire et analogique a permis de montrer le contrôle majeur des courants de marée sur la dynamique sédimentaire actuelle. La morphologie du littoral et des fonds marins renforcent l’intensité des courants tidaux qui facilite les échanges en sables coquilliers entre la rade interne et la mer d’Iroise. Le système est néanmoins en érosion et enregistre un déséquilibre en apports sédimentaires. Les sédiments fins sont remobilisés par les courants de flot et les actions anthropiques colmatant les secteurs peu profonds.(b) L’étude litho- et chronostratigraphique de la séquence sédimentaire, a mis en évidence le recul successif des processus estuariens lors de la dernière remontée du niveau marin (holocène). La morphologie héritée du substratum, combinée à la transgression marine, a fortement influencé l’architecture des dépôts, leur préservation et leurs variations lithologiques latérales et longitudinales. Après la stabilisation du niveau marin (3 000 BP), les variations climatiques (optimum climatique médiéval, et petit âge glaciaire) et les activités anthropiques impactent d’avantage la dynamique des particules en suspension.La rade a donc eu un impact différent sur le transfert des sédiments au cours de la remontée du niveau marin. Actuellement, elle acte comme un « piège à sédiment fin » et enregistre dans le même temps un déficit de stock sédimentaire grossier potentiellement remobilisable. Cette configuration favorise une érosion des parties les plus profondes du système. / The bay of Brest is a tide-dominated, semi-enclosed coastal basin, which is connected with two rivers (Aulne and Elorn). Its jagged shoreline and seabed morphology constitute an ideal setting to understand sedimentary transfer at the land-sea interface. In this aim, this study is divided in two different time scale. The first (a) focuses on the present-day sedimentary bedload dynamic and the second (b) on the reconstruction of the Holocene infilling, during the last marine transgression. (a) A analyse combining a sedimentology approach and numerical has highlighted the major control of the tidal currents. Swells and rivers have a minor impact, because the inherited morphology accentuates and promotes tidal currents. There are responsible of a shelly sandy exchange between the oceanic domain (Iroise Sea) and confined (bay of Brest). At present, the bay of Brest suffers from an imbalance of shelly sand. Fine sediments are eroded and redistributed in the shallow parts of the bay. In ideal conditions (strong tidal current) they can be exported.(b) From the stratigraphic and chronostratigraphic analyses, the successive landward retreat of estuarine processes, during the last marine transgression, has been observed. The sea level acts as the major factor control of the sedimentary geometry deposits. However, the morphological particularity of the bay of Brest influenced their preservation and it is possible to determinate the longitudinal and transversal asymmetry. After the sea level stabilisation (3 000 BP), the Holocene climatic variations and anthropic activities have disturbed the suspension dynamic.The bay of Brest had a different impact on the sedimentary transfer during the last marine transgression. At present, it acts as a « sediment trap » for the fine particles and has not enough sandy sediment. This configuration tends to an erosion of the system.
560

Réponses d'une population aux forçages environnementaux et anthropiques : le suivi à long terme de la crevette Palaemon Longirostris de l'Estuaire de la Gironde (1979-2007)

Béguer, Mélanie 27 November 2009 (has links)
La population de la crevette blanche Palaemon longirostris, espèce résidente des estuaires faisant l’objet d’une pêche traditionnelle, est soumise à des forçages environnementaux (fluctuations naturelles du milieu, modifications du régime hydro-climatique de l’estuaire en lien avec le changement climatique) et anthropiques importants (aspiration dans les circuits du CNPE -Centre Nucléaire de production d’Electricité du Blayais-, pêche ciblée, pollutions etc.). Dans ce contexte et sur la base d’un suivi mensuel, réalisé depuis 1979, complété par des échantillonnages en 2007, cette thèse montre que cette population répond fortement aux changements environnementaux abiotiques et anthropiques. Ainsi, d’importantes fluctuations spatio-temporelles des abondances sont mises en évidence à diverses échelles temporelles, spatiales et biologiques. L’analyse de la série à long terme montre des fortes oscillations interannuelles régulières (période 5/10 ans) en partie liées aux facteurs environnementaux et aux variations du recrutement. Une diminution de l’abondance globale, ainsi qu’un déplacement vers l’amont de cette population, sont également constatés. Ce déclin est attribué aux fortes variations et nombreuses modifications des traits de vie de l’espèce –reproduction, -croissance, -mortalité, démontrées au cours de l’étude. La présence de déformations de l’exosquelette, étudiée aussi via un élevage de plusieurs mois, révèle par ailleurs, de forts impacts négatifs à l’échelle individuelle (mortalité). De plus, des simulations réalisées à partir d’un modèle matriciel de dynamique de population élaboré durant l’étude, montrent la synergie des pressions anthropiques par prélèvements (CNPE, pêche) et des forçages environnementaux, ainsi que l’importance des processus de déplacement dans le fonctionnement de cette population. Cette étude démontre finalement l’intérêt que revêt cette population et plus largement les populations de crevettes estuariennes, pour l’étude du fonctionnement et du diagnostic de l’état des écosystèmes estuariens. De nouvelles métriques originales sont proposées, lesquelles ouvrent vers la voie vers de nouveaux indicateurs. / The white shrimp, Palaemon longirostris, is an estuarine species and an important fishing resource. This species therefore encounters an important environmental forcing (natural fluctuations of the environment, modifications of the hydro-climatic regime of the estuary associated with the climate change) and an anthropological forcing (drawing up by the circuits of the CNPE - Nuclear center of electricity production of Blayais-, targeted fishing, pollutions etc.). In this context and on the basis of a monthly survey in place since 1979 and completed in 2007, this study shows that this population is strongly influenced by environmental and anthropological changes. Important spatio-temporal variations in the shrimp abundance are highlighted at different temporal, spatial and biological scales. A long-term analysis underlines strong regular interannual oscillations (5/10-year period) partially linked with environmental factors and recruitment variations. A decrease in the global abundance and a movement of this population towards the upstream part of the estuary are also displayed. In this study, the decline is attributed to strong variations and numerous modifications in the life history traits of the species - reproduction, - growth, - mortality. The presence of exoskeletal deformities, alternatively studied via a rearing of several months, reveals strong negative impacts at the individual scale (mortality). Furthermore, simulations based on a population-matrix model, developed during the study, show the synergy of the anthropological pressure by capture (CNPE, fishing) and the environmental forcing, as well as the importance of movement processes in the population dynamics. This study finally demonstrates the interest of this population, and more widely of the estuarine shrimp populations, in the understanding of the functioning and the diagnosis of the estuarine ecosystem state. New original metrics are proposed, opening the way towards new indicators.

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