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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.
11

Development, Validation, and Evaluation of a Continuous, Real-time, Bivalve Biomonitoring System

Allen, H. Joel 12 1900 (has links)
A biological monitoring tool to assess water quality using bivalve gape behavior was developed and demonstrated. The purpose of this work was to develop methodologies for screening water quality appropriate to the goals of the watershed paradigm. A model of bivalve gape behavior based on prediction of behavior using autoregressive techniques was the foundation of the bivalve biomonitoring system. Current technology was used in developing the system to provide bivalve gape state data in a continuous real-time manner. A laboratory version of the system, including data collection and analysis hardware and software, was developed for use as a toxicological assay for determination of effective concentrations of toxicant(s) or other types of stress on bivalve gape behavior. Corbicula fluminea was monitored and challenged with copper, zinc, and chlorpyrifos using the system. Effective concentrations of 176±23µg/L copper, 768±412µg/L zinc, and 68µg/L chlorpyrifos were observed using a natural water with high dissolved organic carbon concentrations. A rugged field version of the bivalve biomonitoring system was developed and deployed in two locations. The field systems were fitted with a photovoltaic array, a single board computer, and a CDPD telemetry modem for robust remote operation. Data were telemetered at a time relevant rate of once every ten minutes. One unit was deployed in Lake Lewisville, Denton County, TX in February 2000. Data were telemetered and archived at a 92% success rate. Bivalve gape data demonstrated significant behavioral deviations on average 5 times per month. A second unit was deployed in Pecan Creek, Denton, TX in June 2001. Data from this site were telemetered and archived at a 96% success rate. Over the months of June-August 2001, 16 significant behavioral deviations were observed, 63% of which were correlated with changes in physical/chemical parameters. This work demonstrated the relative sensitivity of bivalve gape as a toxicological endpoint and the feasibility of its use in a continuous, real-time, bivalve biomonitoring system. Technical aspects of collecting, telemetering, and analyzing this type of data in a time-relevant manner were developed resulting in a system appropriate for use as a means of data collection within the watershed paradigm.
12

"Avaliação da poluição atmosférica por metais na região metropolitana de São Paulo utilizando a Bromélia Tillandsia Usneoides L. como biomonitor" / AVALIAÇÃO DA POLUIÇÃO ATMOSFÉRICA POR METAIS NA REGIÃO METROPOLITANA DE SÃO PAULO, BRASIL, UTILIZANDO A BROMÉLIA TILLANDSIA USNEOIDES L. COMO BIOMONITOR

Nogueira, Cláudio Ailton 14 September 2006 (has links)
Tillandsia usneoides L. é uma bromélia que vive em árvores ou em outros substratos inertes, absorvendo água e nutrientes diretamente do ambiente, sem apresentar raízes. Devido às suas características morfológicas e fisiológicas, esta espécie acumula os poluentes presentes na atmosfera. No presente trabalho, Tillandsia usneoides foi usada como biomonitor de poluição atmosférica por metais em São Paulo, Brasil, que é a maior cidade da América do Sul, com uma população de cerca de 18 milhões de habitantes e uma forte atividade industrial. A área urbana é poluída por emissões industriais mas, de acordo com a Companhia de Tecnologia de Saneamento Ambiental do Estado de São Paulo (CETESB), a agência governamental de controle de qualidade do ar, emissões regulares de cerca de 7,8 milhões de veículos motores são a principal fonte de poluição do ar. As amostras de Tillandsia foram coletadas em um local considerado não poluído e foram expostas por períodos de dois meses em 10 locais da cidade com diferentes níveis de poluição, e em um local de controle. Após a exposição, os metais foram analisados na planta por análise por ativação com nêutrons e por ICP-MS (Pb, Cd, Co, Cu, Ni, Sb e V). Os resultados obtidos mostraram uma concentração notável de Co e Ni nas plantas expostas em uma área industrial, onde existe uma indústria de processamento de metal, que produz cerca de 600 ton/ano de Co e 16.000 ton/ano de Ni. Cobre e crômio se apresentaram igualmente distribuídos em regiões industriais e em locais próximos a avenidas com tráfego intenso, sugerindo que estes elementos podem ser associados tanto a fontes veiculares como industriais. O acúmulo de Cd verificado nas plantas expostas em áreas industriais indica as atividades intrópicas como a principal fonte desse elemento. Não foram identificadas fontes evidentes para o Pb, uma vez que este elemento se apresentou igualmente espalhado por todos os locais de monitoramento. Elementos ligados ao tráfego, como Zn, Ba and Sb apresentaram altas concentrações em plantas expostas em locais situados próximos a avenidas com tráfego pesado (carros, ônibus e caminhões) e podem ser associados a fontes veiculares. Para Zn, os maiores teores foram relacionados a zonas industriais, e este elemento pode ser também associado à presença de fontes de emissão antrópicas. Os elementos terras raras, Fe e Rb, provavelmente têm as partículas de solo como principal fonte. / Tillandsia usneoides L. is an epiphytic bromeliad that lives on trees or other kinds of inert substrates, absorbing water and nutrients directly from the environment without roots. Due to its morphological and physiological characteristics, this species accumulates the pollutants present in the atmosphere. In the present work, Tillandsia usneoides was used as a biomonitor of metal atmospheric pollution in São Paulo, Brazil, which is the biggest city in South America with a population of 18 million inhabitants and a strong industrial activity. The urban area is polluted by industrial emissions but, according to the Environmental Protection Agency of the State of São Paulo (CETESB), the governmental agency of air quality control, regularly occurring emissions from about 7.8 million motor vehicles provide the principal source of air pollution. The Tillandsia samples were collected from an unpolluted area and were exposed bimonthly in 10 sites of the city with different pollution levels and in a control site. After exposure, trace metals were analyzed in the plant by instrumental neutron activation analysis and ICP-MS (Pb, Cd, Co, Cu, Ni, Sb e V). The results of the investigation showed a notable concentration of Co and Ni in the plants exposed in an industrial area where there is a metal processing plant, which produces about 600 tons/year of Co and 16,000 tons/year of Ni. Copper and chromium were equally distributed in industrial regions and in sites near heavy traffic avenues, suggesting that these elements can be associated to both vehicular and industrial sources. A high accumulation of Cd in the plant exposed in industrial areas indicates industrial activities as the main source of this element. For Pb, no evident sources could be identified so far as it was spread evenly along the monitoring sites. Traffic-related elements such as Zn, Ba and Sb presented high concentrations in plants exposed in sites near to heavy traffic avenues (cars, buses and trucks) and may be associated to vehicular sources. For Zn, the highest contents were related to industrial zones and this element can be associated to the presence of anthropogenic emission sources. The rare earth elements, Fe and Rb, probably have soil particles as main source.
13

"Avaliação da poluição atmosférica por metais na região metropolitana de São Paulo utilizando a Bromélia Tillandsia Usneoides L. como biomonitor" / AVALIAÇÃO DA POLUIÇÃO ATMOSFÉRICA POR METAIS NA REGIÃO METROPOLITANA DE SÃO PAULO, BRASIL, UTILIZANDO A BROMÉLIA TILLANDSIA USNEOIDES L. COMO BIOMONITOR

Cláudio Ailton Nogueira 14 September 2006 (has links)
Tillandsia usneoides L. é uma bromélia que vive em árvores ou em outros substratos inertes, absorvendo água e nutrientes diretamente do ambiente, sem apresentar raízes. Devido às suas características morfológicas e fisiológicas, esta espécie acumula os poluentes presentes na atmosfera. No presente trabalho, Tillandsia usneoides foi usada como biomonitor de poluição atmosférica por metais em São Paulo, Brasil, que é a maior cidade da América do Sul, com uma população de cerca de 18 milhões de habitantes e uma forte atividade industrial. A área urbana é poluída por emissões industriais mas, de acordo com a Companhia de Tecnologia de Saneamento Ambiental do Estado de São Paulo (CETESB), a agência governamental de controle de qualidade do ar, emissões regulares de cerca de 7,8 milhões de veículos motores são a principal fonte de poluição do ar. As amostras de Tillandsia foram coletadas em um local considerado não poluído e foram expostas por períodos de dois meses em 10 locais da cidade com diferentes níveis de poluição, e em um local de controle. Após a exposição, os metais foram analisados na planta por análise por ativação com nêutrons e por ICP-MS (Pb, Cd, Co, Cu, Ni, Sb e V). Os resultados obtidos mostraram uma concentração notável de Co e Ni nas plantas expostas em uma área industrial, onde existe uma indústria de processamento de metal, que produz cerca de 600 ton/ano de Co e 16.000 ton/ano de Ni. Cobre e crômio se apresentaram igualmente distribuídos em regiões industriais e em locais próximos a avenidas com tráfego intenso, sugerindo que estes elementos podem ser associados tanto a fontes veiculares como industriais. O acúmulo de Cd verificado nas plantas expostas em áreas industriais indica as atividades intrópicas como a principal fonte desse elemento. Não foram identificadas fontes evidentes para o Pb, uma vez que este elemento se apresentou igualmente espalhado por todos os locais de monitoramento. Elementos ligados ao tráfego, como Zn, Ba and Sb apresentaram altas concentrações em plantas expostas em locais situados próximos a avenidas com tráfego pesado (carros, ônibus e caminhões) e podem ser associados a fontes veiculares. Para Zn, os maiores teores foram relacionados a zonas industriais, e este elemento pode ser também associado à presença de fontes de emissão antrópicas. Os elementos terras raras, Fe e Rb, provavelmente têm as partículas de solo como principal fonte. / Tillandsia usneoides L. is an epiphytic bromeliad that lives on trees or other kinds of inert substrates, absorbing water and nutrients directly from the environment without roots. Due to its morphological and physiological characteristics, this species accumulates the pollutants present in the atmosphere. In the present work, Tillandsia usneoides was used as a biomonitor of metal atmospheric pollution in São Paulo, Brazil, which is the biggest city in South America with a population of 18 million inhabitants and a strong industrial activity. The urban area is polluted by industrial emissions but, according to the Environmental Protection Agency of the State of São Paulo (CETESB), the governmental agency of air quality control, regularly occurring emissions from about 7.8 million motor vehicles provide the principal source of air pollution. The Tillandsia samples were collected from an unpolluted area and were exposed bimonthly in 10 sites of the city with different pollution levels and in a control site. After exposure, trace metals were analyzed in the plant by instrumental neutron activation analysis and ICP-MS (Pb, Cd, Co, Cu, Ni, Sb e V). The results of the investigation showed a notable concentration of Co and Ni in the plants exposed in an industrial area where there is a metal processing plant, which produces about 600 tons/year of Co and 16,000 tons/year of Ni. Copper and chromium were equally distributed in industrial regions and in sites near heavy traffic avenues, suggesting that these elements can be associated to both vehicular and industrial sources. A high accumulation of Cd in the plant exposed in industrial areas indicates industrial activities as the main source of this element. For Pb, no evident sources could be identified so far as it was spread evenly along the monitoring sites. Traffic-related elements such as Zn, Ba and Sb presented high concentrations in plants exposed in sites near to heavy traffic avenues (cars, buses and trucks) and may be associated to vehicular sources. For Zn, the highest contents were related to industrial zones and this element can be associated to the presence of anthropogenic emission sources. The rare earth elements, Fe and Rb, probably have soil particles as main source.
14

The inorganic pollution of the Franschhoek River : sources and solutions

Adams, Kim Marie January 2011 (has links)
<p>The aim of the study was to quantify the extent of inorganic chemical pollution of the Franschhoek River and draw relationships between contaminants in water, sediment and plants. The invasive Acacia mearnsii and Salix babylonica and indigenous Brabejum stellatifolium species were chosen as biomonitors due to their wide spread distribution along the river and their apparent ability to accumulate heavy metals. The sites chosen allowed for comparison of the river quality upstream with that of the river further down stream as it meandered through residential, agricultural and recreational areas, until it joined with the Berg River further downstream. The general aim of the study was to assess the degree of inorganic pollution in the Franschhoek River to evaluate its contribution to pollution of the Berg River, of which it is an important tributary. Also understanding the sources of the pollution would contribute to the ability to reduce pollution.</p>
15

The inorganic pollution of the Franschhoek River : sources and solutions

Adams, Kim Marie January 2011 (has links)
<p>The aim of the study was to quantify the extent of inorganic chemical pollution of the Franschhoek River and draw relationships between contaminants in water, sediment and plants. The invasive Acacia mearnsii and Salix babylonica and indigenous Brabejum stellatifolium species were chosen as biomonitors due to their wide spread distribution along the river and their apparent ability to accumulate heavy metals. The sites chosen allowed for comparison of the river quality upstream with that of the river further down stream as it meandered through residential, agricultural and recreational areas, until it joined with the Berg River further downstream. The general aim of the study was to assess the degree of inorganic pollution in the Franschhoek River to evaluate its contribution to pollution of the Berg River, of which it is an important tributary. Also understanding the sources of the pollution would contribute to the ability to reduce pollution.</p>
16

Cladonia verticillaris (líquen) como biomonitor padrão da qualidade do ar no distrito de Jaboatão-PE

SILVA, Rita Alves January 2002 (has links)
Made available in DSpace on 2014-06-12T18:07:39Z (GMT). No. of bitstreams: 2 arquivo8344_1.pdf: 2911564 bytes, checksum: b1951dd981c6652122c54a6c2a84a7e5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2002 / Os liquens são reconhecidos como bioindicadores de ambientes e biomonitores da qualidade do ar atmosférico. Neste trabalho selecionou-se o Distrito de Jaboatão, situado na Mesoregião Metropolitana do Recife (RMR), Pernambuco, Brasil, para avaliar a qualidade do ar naquela área, correlacionando os dados fornecidos pelos monitores biológicos liquens, com os resultados obtidos das estações de monitoramento mecânico instaladas pela Companhia Pernambucana de Meio Ambiente (CPRH). Líquen da espécie (Raddi.) Fr. foi o biomonitor utilizado. A espécie foi coletada sobre solos arenosos de tabuleiros costeiros (cerrado) da Paraíba, nas seguintes localidades: Mamanguape, na Reserva Biológica de Guaribas, e em Alhandra, às margens da BR 101 (PB). Os biomonitores ativos foram coletados e acondicionados em recipientes plásticos, bem como o solo de área de ocorrência. Experimentos de transplante do material liquênico foram montados junto às estações de medição da CPRH localizadas na Estação do Metrô (ponto 1) e da CHESF (ponto 2) no referido distrito. As amostras de ambas as localidades foram coletadas em março de 2000, e imediatamente expostas ao ambiente nos pontos de experimento. Após 12 e 18 meses de exposição aos poluentes amostras foram retiradas e analisadas, química e fisiologicamente. Foram quantificados por Espectrômetro de Emissão Atômica por Plasma Indutivamente Aplicado (ICP/AES) os teores de Pb, Cd, Fe, Cu, Mn, Zn, Cr, Ni e Ca. Parte das mesmas amostras foram extraídas por sistema de esgotamento a frio com acetona, e analisadas por cromatografia em camada delgada (CCD) e cromatografia líquida de alta eficiência (CLAE) para identificação e quantificação dos fenóis liquênicos nas amostras. Filtros dos amostradores de grandes volumes (Hi-vol) da CPRH foram analisados, e neles quantificados Pb, Cd, Fe, Cu, Mn, Cr, Zn e Ni. Para este experimento foram consideradas as amostras representativas para as maiores concentrações mensais de Poeira Total em Suspensão (PTS), cujos filtros foram recolhidos no mesmo período em que os biomonitores. Os metais pesados supra referidos foram determinados via Espectrofotometria de Absorção Atômica por Chama (EAA). Para averiguação do comportamento de" % sob condições laboratoriais, foram montados experimentos onde amostras do líquen foram diariamente borrifadas com soluções de acetato de chumbo de chumbo a 1%, 0,1%, e água deionizada como controle. Foram coletadas amostras a 24h, 48h, 5dias e 10 dias, sendoposteriormente analisadas, segundo os mesmos parâmetros já referidos para o material exposto às condições ambientais. Ao final, as amostras mais preservadas e as em maior estado de deterioração, tanto as de experimento em campo, como as de laboratório, foram analisadas por microscopia eletrônica de varredura. Os resultados demonstraram que todas elas tiveram prejuízo na síntese de fenóis comuns da espécie. Análises em CCD e CLAE comprovaram a ocorrência de substâncias distintas das detectadas nas amostras padrão. Nos ensaios em CLAE ficou comprovado que os poluentes prejudicaram a síntese de fenóis tanto no aspecto qualitativo (substâncias intermediárias das vias metabólicas), mas também no teor das substâncias produzidas no total. Foi evidenciada a produção do ácido protocetrárico, além do hipoprotocetrárico e seu aldeído, como compostos intermediários. Sugeriu-se que o baixo teor de substâncias, e/ou a produção de metabólitos intermediários das rotas metabólicas tenha sido causado por um prejuízo na fotossíntese do fotobionte, por acidificação da célula pelos poluentes, o bloqueio de reações enzimáticas pelos elementos que contaminaram o líquen, ou a associação desses fatores. Em relação à quantificação dos contaminantes, houve o predomínio do Pb, Fe, Ca, Mn , Zn e Cr nas amostras de líquen. Nos filtros recolhidos das estações de monitoramento mecânico, detectou-se em maior concentração o Fe, Cu, Mn e Zn. No material submetido ao acetato de chumbo de chumbo foi verificado que o número de dias de exposição (10) foi suficiente para prejudicar o líquen no aspecto fisiológico. Análises por microscopia eletronica de varrredura (MEV) revelaram uma total desordem na superfície do talo liquênico, após exposição aos poluentes. As células do fotobionte, não visualizadas nas amostras controle, foram facilmente expostas, tornando-se desprotegidas em meio com alto nível de contaminantes. Dados semelhantes foram obtidos para os experimentos em laboratório. A superfície de" iniciou um processo de esfoliação resultando na sua destruição. Foi possível concluir que a zona central da cidade, onde encontra-se a estação do Metrô, é a mais poluída, e que" % como biomonitor, demonstrou capacidade de registrar os mais ínfimos níveis de contaminantes, inclusive quanto a bioacumulação de elementos iônicos, nutrientes e tóxicos e, diante desse contexto, valida a sua utilização como mais um parâmetro para avaliação da qualidade ambiental, em especial do ar atmosféricosubsequently analyzed using the same parameters mentioned above for the material exposed to environmental conditions. At the end, the best preserved samples and a greater state of deterioration, both in the field of experiment, such as laboratory, were analyzed by scanning electron microscopy. The results showed they all had impaired synthesis of phenols common species. Analyses in TLC and HPLC confirmed the presence of substances other than those detected in standard samples. In trials it was proved that HPLC pollutants impaired synthesis of phenols in both the qualitative aspect (intermediates of metabolic pathways), but also the content of the substances produced in total. Was evidenced protocetrárico acid production, and its addition to hipoprotocetrárico aldehyde as intermediate compounds. It has been suggested that low levels of substances, and / or the production of intermediate metabolites of the metabolic pathways have been caused by a loss in the photobiont photosynthesis, acidification of the cell by pollutants, the blockade of enzymatic reactions of the elements that have polluted the lichen, or a combination of these factors. Regarding the quantification of contaminants, there was predominance of Pb, Fe, Ca, Mn, Zn and Cr in samples of lichen. In filters collected from monitoring stations mechanic, was detected at higher concentration Fe, Cu, Mn and Zn. In material submitted to the lead acetate Lead was found that the number of days of exposure (10) was sufficient to affect the lichen physiological aspect. Analysis by electron microscopy varrredura (SEM) revealed a total disorder in the surface of the lichen thallus, after exposure to pollutants. The photobiont cells, not seen in samples control, were easily exposed, making it unprotected in a medium with high of contaminants. Similar data were obtained for the experiments the laboratory. The surface? " ? ?????? ? initiated a process of exfoliation resulting in its destruction. It was concluded that the downtown area, where is the subway station, is the most polluted, and that? " ? ?????? ?% As biomonitor showed ability to record the smallest levels of contaminants, including as to bioaccumulation of ionic elements, nutrients and toxic and, given this context, validates its use as an additional parameter for the assessment of environmental quality, in particular the atmospheric air.
17

The inorganic pollution of the Franschhoek River : sources and solutions

Adams, Kim Marie January 2011 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / The aim of the study was to quantify the extent of inorganic chemical pollution of the Franschhoek River and draw relationships between contaminants in water, sediment and plants. The invasive Acacia mearnsii and Salix babylonica and indigenous Brabejum stellatifolium species were chosen as biomonitors due to their wide spread distribution along the river and their apparent ability to accumulate heavy metals. The sites chosen allowed for comparison of the river quality upstream with that of the river further down stream as it meandered through residential, agricultural and recreational areas, until it joined with the Berg River further downstream. The general aim of the study was to assess the degree of inorganic pollution in the Franschhoek River to evaluate its contribution to pollution of the Berg River, of which it is an important tributary. Also understanding the sources of the pollution would contribute to the ability to reduce pollution. / South Africa
18

De l’acclimatation à l’adaptation : mécanismes évolutifs, conséquences populationnelles et implication en biosurveillance / From acclimation to adaptation : evolutionary mechanisms, populational consequences, and implications for biomonitoring

Potet, Marine 21 December 2017 (has links)
Le cadre réglementaire défini par la Directive Cadre sur l’Eau impose le développement de méthodologies fiables d’évaluation et/ou de caractérisation de l’état de santé des écosystèmes aquatiques. L’objectif de ce travail de thèse était d’identifier les rôles relatifs des paramètres des milieux aquatiques (température, cycle saisonnier, minéralisation), des caractéristiques des populations et des pressions anthropiques sur les réponses des biomarqueurs chez un organisme aquatique modèle, la moule zébrée (Dreissena polymorpha). Une espèce sœur, Dreissena rostriformis bugensis, arrivée plus récemment dans nos cours d’eau, a été suivie en parallèle et son potentiel en tant que biomoniteur a également été évalué. Pour cela, une batterie d’une douzaine de biomarqueurs sub-cellulaires a été mesurée dans différentes populations des deux espèces vivant dans des milieux contrastés, à différentes périodes de l’année, mais aussi lors de stress standardisés en laboratoire. Les biomarqueurs choisis correspondaient à différentes fonctions physiologiques et/ou antitoxiques, et des réponses à fortes pertinence écologiques, telles que la consommation d’oxygène ou l’activité de filtration, ont ponctuellement été suivies. Ces différents paramètres ont permis d’interroger les notions de sensibilité et de vulnérabilité des populations et de mieux comprendre les facteurs déterminant les réponses des biomarqueurs. Les différences inter-populationnelles montrent que l’accumulation des contaminants par les organismes et leurs réponses biologiques sont bien dépendantes de la qualité du biotope propre à chaque population, mais aussi de la saison, un facteur confondant qui doit donc être pris en compte lors de campagnes de biosurveillance. De fortes différences de réponse des biomarqueurs entre les deux espèces ont aussi été observées, aussi bien in situ que lors des expositions en laboratoire, soulignant la nécessité de bien différencier ces deux espèces, pourtant très proches. La nouvelle arrivée, D. r. bugensis, présente des réponses plus plastiques in situ, mais semble moins capable de gérer des stress aigus lors d’expositions en laboratoire. A l’inverse, D. polymorpha, arrivée il a 200 ans en France, semble mieux adaptée, avec une variabilité de réponse moins marquée et une meilleure tolérance aux contaminants. Ces travaux de thèse s’inscrivent dans le cadre de la convention BIOMICS, réalisée en collaboration avec l’ONEMA. Ils montrent que ces deux espèces sont aptes à nous renseigner sur l’état de contamination du milieu dans lequel elles vivent, même si les grilles d’interprétation peuvent être différentes de l’une à l’autre. Les variations des réponses des biomarqueurs au niveau sub-cellulaire témoignent de façon précoce de modifications de la qualité du milieu. Certains biomarqueurs semblent toutefois plus informatifs que d’autres, la batterie mesurée pourrait donc être réduite. A l’avenir, ces travaux permettront une meilleure lecture et interprétation des biomarqueurs mesurés dans des populations autochtones ou transplantées, et attestent de l’intérêt des biomarqueurs en tant qu’outils d’évaluation de la qualité des milieux aquatiques / The regulatory framework defined by the Water Framework Directive requires the development of reliable methodologies for assessing and / or characterizing the health status of aquatic ecosystems. The objective of this thesis was to identify the relative roles of environmental parameters (temperature, seasonal cycle, mineralization), population characteristics and anthropic pressures on biomarker responses in a model aquatic organism, the zebra mussel (Dreissena polymorpha). A sister species, Dreissena rostriformis bugensis, which invaded more recently our waterways, has been used in parallel and its potential as a biomonitor has also been evaluated. For this purpose, a battery of a dozen sub-cellular biomarkers was measured in different populations of the two species living in contrasting environments, at different times of the year, but also under laboratory stresses. The selected biomarkers corresponded to different physiological and / or antitoxic functions, and responses with high ecological relevance, such as oxygen consumption or filtration activity, were occasionally followed. These various parameters allowed to question the concepts of sensitivity and vulnerability of the populations and to understand the factors determining biomarker responses. Inter-population differences showed that the accumulation of contaminants by organisms and their biomarker responses depend on environmental quality at the originating site of each population, but also on the season, a confounding factor which must therefore be taken into account during biomonitoring programs. Strong differences in biomarker responses between the two species were also observed, both in situ and during laboratory experiments, emphasizing the need to differentiate the two species, so close they are. The recent invader, D. r. bugensis, presents more plastic responses in situ, but appears less able to manage acute stress in laboratory. Conversely, D. polymorpha, which is about 200 years old in France, appears to be better adapted, with less response variability and a better tolerance to contaminants. This thesis work is part of the BIOMICS convention, carried out in collaboration with ONEMA. It shows that these two species are able to inform about the contamination status of their environment. Variations in biomarker responses at the sub-cellular level indicate early changes in environmental quality. Some biomarkers, however, seem more informative than others do, so the measured battery could be reduced. In the future, this work will allow a better reading and interpretation of biomarkers measured in autochthonous or transplanted populations, and attest the value of biomarkers as tools for assessing aquatic environment quality
19

Untersuchungen zur Einsatzmöglichkeit der Dreikantmuschel Dreissena polymorpha als biologischer Filter und Wasserhygienemonitor

Schröter-Bobsin, Ute 20 April 2005 (has links) (PDF)
Dreikantmuscheln (Dreissena polymorpha) sind aufgrund ihrer speziellen Ernährungsweise in der Lage, erhebliche Wassermengen unterschiedlichster Qualität sehr effektiv zu filtrieren und dabei zu reinigen (Biofilter). Ziel der Arbeit waren Einschätzungen zum Leistungsumfang, der Nutzung und von Grenzen des Muschelfilters. Die Exposition der Muscheln erfolgte in der Elbe am Neustädter Hafen in Dresden (Oberflächengewässer), in dem ersten und zweiten Schönungsteich der Kläranlage Reichenau (Sachsen) und in einem Waldbad in Langebrück (Badegewässer). Eine wirksame Elutionsmethode war die Grundlage um Mikroorganismen (Bakterien, Viren und Parasiten) aus dem Muschelgewebe effizient nachweisen zu können. Die bakterielle Wiederfindungsrate von 86% und eine Wiederfindung von 97% für Bakteriophagen bestätigen die Elutionseffizienz des Verfahrens. Die Befähigung von Dreissena polymorpha zu einer saisonal beeinflussten Bioakkumulation gegenüber dem Umgebungswasser konnte durch ein Monitoring mit einem Anreicherungsfaktor für Bakterien von 87 (gemittelt) und für Bakteriophagen von 261 (gemittelt) eindrucksvoll bestätigt werden. Batchversuche im Labormaßstab bestätigten die im in situ - Monitoring ermittelte Bakterienakkumulation und demonstrieren darüber hinaus eine temperaturabhängige Inaktivierung (Elimination) der Bakterien (Intestinale Enterokokken) durch die Muscheln mit Reduktionsraten von -77% bei 20°C bzw. -61% bei 6°C. Nicht alle aufgenommenen Organismen werden durch die Muscheln inaktiviert. Das ergaben die in situ Sedimentuntersuchungen unter dem Muschelfilter. Die Verdopplung der Enterokokken sowie die erhöhten Werte der somatischen Coliphagen im Sediment unter Muschelbesatz charakterisieren dieses Kompartiment als Keimreservoir. Die bakterielle Besiedlung des Verdauungstraktes von Dreissena polymorpha wird stark durch die Bakterienzönose des umgebenden Wassers beeinflusst. Sowohl im Wasser als auch im Muschelgewebe dominierten fünf Bakterienstämme (Actinobacteria, Proteobacteria, Bacteroidetes, Firmicutes,&amp;quot;environmental group&amp;quot;). Eine auffallend hohe Dominanz zeigten die Mycoplasmen (Firmicutes), was auf eine mögliche ökologische Nische für Vertreter dieser Gattung in der Muschel hindeutet. In allen Muscheleluaten des Monitorings wurden Legionellen nachgewiesen. Die Muscheln des Teiches 2 der KA Reichenau zeigten mit 86% die höchste Kontamination aller Expositionsorte. Legionellenamplifikate im Muscheleluat 2 gingen kontinuierlich mit ebenfalls positiven Befunden im Wasser einher, so dass der Einsatz von Dreissena polymorpha auch im Biomonitoring von Legionellaceae möglich ist. Erstmalig wurden in der Elbe und im Abwasser der KA Reichenau E. coli O157:H7 infizierenden Phagen und deren Anteile nachgewiesen. Die Elbe lag mit einem E. coli O157:H7 infizierenden Phagenanteil von 7,5% deutlich über dem Rohabwasser (1,0%) und dem Zulauf zum ersten Schönungsteich der Kläranlage (0,5%). Der Stx Gennachweis im Muscheleluat war dagegen nur in einer von 24 Proben erfolgreich. Enterale Viren (AdV, EV) wurden in den Dreikantmuscheln und ihrem Umgebungswasser diskontinuierlich nachgewiesen. Enteroviren wurden im Wasser (57% gemittelt) häufiger als in der parallelen Muschelproben (10%) nachgewiesen. Parasiten (Giardia lamblia und Cryptosporidium parvum) werden durch die exponierten Muscheln aufgenommen, dies bestätigten die qualitativen Testergebnisse. In den Dreikantmuscheln wurde sowohl für G. lamblia (78%), als auch für Cryptosporidien (77%) eine durchschnittlich höhere Nachweisrate im Vergleich zu den korrespondierenden Wasserproben (42% und 36%) ermittelt. Die effiziente Akkumulation und die Umweltresistenz der Dreikantmuscheln sind hervorragende Eigenschaften, die sich zu einem zuverlässigen Biomonitor mit &amp;quot;Hygienegedächtnis&amp;quot; und hoher Sensibilität vereinen lassen.
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Untersuchungen zur Einsatzmöglichkeit der Dreikantmuschel Dreissena polymorpha als biologischer Filter und Wasserhygienemonitor

Schröter-Bobsin, Ute 25 April 2005 (has links)
Dreikantmuscheln (Dreissena polymorpha) sind aufgrund ihrer speziellen Ernährungsweise in der Lage, erhebliche Wassermengen unterschiedlichster Qualität sehr effektiv zu filtrieren und dabei zu reinigen (Biofilter). Ziel der Arbeit waren Einschätzungen zum Leistungsumfang, der Nutzung und von Grenzen des Muschelfilters. Die Exposition der Muscheln erfolgte in der Elbe am Neustädter Hafen in Dresden (Oberflächengewässer), in dem ersten und zweiten Schönungsteich der Kläranlage Reichenau (Sachsen) und in einem Waldbad in Langebrück (Badegewässer). Eine wirksame Elutionsmethode war die Grundlage um Mikroorganismen (Bakterien, Viren und Parasiten) aus dem Muschelgewebe effizient nachweisen zu können. Die bakterielle Wiederfindungsrate von 86% und eine Wiederfindung von 97% für Bakteriophagen bestätigen die Elutionseffizienz des Verfahrens. Die Befähigung von Dreissena polymorpha zu einer saisonal beeinflussten Bioakkumulation gegenüber dem Umgebungswasser konnte durch ein Monitoring mit einem Anreicherungsfaktor für Bakterien von 87 (gemittelt) und für Bakteriophagen von 261 (gemittelt) eindrucksvoll bestätigt werden. Batchversuche im Labormaßstab bestätigten die im in situ - Monitoring ermittelte Bakterienakkumulation und demonstrieren darüber hinaus eine temperaturabhängige Inaktivierung (Elimination) der Bakterien (Intestinale Enterokokken) durch die Muscheln mit Reduktionsraten von -77% bei 20°C bzw. -61% bei 6°C. Nicht alle aufgenommenen Organismen werden durch die Muscheln inaktiviert. Das ergaben die in situ Sedimentuntersuchungen unter dem Muschelfilter. Die Verdopplung der Enterokokken sowie die erhöhten Werte der somatischen Coliphagen im Sediment unter Muschelbesatz charakterisieren dieses Kompartiment als Keimreservoir. Die bakterielle Besiedlung des Verdauungstraktes von Dreissena polymorpha wird stark durch die Bakterienzönose des umgebenden Wassers beeinflusst. Sowohl im Wasser als auch im Muschelgewebe dominierten fünf Bakterienstämme (Actinobacteria, Proteobacteria, Bacteroidetes, Firmicutes,&amp;quot;environmental group&amp;quot;). Eine auffallend hohe Dominanz zeigten die Mycoplasmen (Firmicutes), was auf eine mögliche ökologische Nische für Vertreter dieser Gattung in der Muschel hindeutet. In allen Muscheleluaten des Monitorings wurden Legionellen nachgewiesen. Die Muscheln des Teiches 2 der KA Reichenau zeigten mit 86% die höchste Kontamination aller Expositionsorte. Legionellenamplifikate im Muscheleluat 2 gingen kontinuierlich mit ebenfalls positiven Befunden im Wasser einher, so dass der Einsatz von Dreissena polymorpha auch im Biomonitoring von Legionellaceae möglich ist. Erstmalig wurden in der Elbe und im Abwasser der KA Reichenau E. coli O157:H7 infizierenden Phagen und deren Anteile nachgewiesen. Die Elbe lag mit einem E. coli O157:H7 infizierenden Phagenanteil von 7,5% deutlich über dem Rohabwasser (1,0%) und dem Zulauf zum ersten Schönungsteich der Kläranlage (0,5%). Der Stx Gennachweis im Muscheleluat war dagegen nur in einer von 24 Proben erfolgreich. Enterale Viren (AdV, EV) wurden in den Dreikantmuscheln und ihrem Umgebungswasser diskontinuierlich nachgewiesen. Enteroviren wurden im Wasser (57% gemittelt) häufiger als in der parallelen Muschelproben (10%) nachgewiesen. Parasiten (Giardia lamblia und Cryptosporidium parvum) werden durch die exponierten Muscheln aufgenommen, dies bestätigten die qualitativen Testergebnisse. In den Dreikantmuscheln wurde sowohl für G. lamblia (78%), als auch für Cryptosporidien (77%) eine durchschnittlich höhere Nachweisrate im Vergleich zu den korrespondierenden Wasserproben (42% und 36%) ermittelt. Die effiziente Akkumulation und die Umweltresistenz der Dreikantmuscheln sind hervorragende Eigenschaften, die sich zu einem zuverlässigen Biomonitor mit &amp;quot;Hygienegedächtnis&amp;quot; und hoher Sensibilität vereinen lassen.

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