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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.
1

Avaliação ecotoxicológica de compostos naturais produzidos por Eucalyptus grandis e Eucalyptus urophylla no Vale do Rio Doce, Minas Gerais / Ecotoxicological evaluation of natural compounds produced by Eucalyptus grandis and Eucalyptus urophylla in the Valley of Rio Doce, Minas Gerais State

Zoratto, Ana Cristina 31 August 2007 (has links)
Tendo como base o escasso conhecimento dos efeitos causados por eucaliptos sobre a biota aquática e o intenso plantio em áreas de entorno de inúmeros lagos no Vale do rio Doce, o presente estudo avaliou a extração, identificação e os efeitos tóxicos dos compostos naturais presentes nas folhas de Eucalyptus grandis e E. urophylla das áreas de entorno das lagoas Palmeirinha e Ferruginha, respectivamente, através de destilação por arraste a vapor de água, cromatografia gasosa de alta resolução (CGC), análise por infravermelho e testes ecotoxicológicos com as águas de decomposição das folhas (laboratório), com os óleos essenciais, extratos hidroalcólicos e aquosos das folhas da serapilheira, 30 e 60 dias após contato com as lagoas. Nos testes de toxicidade foram utilizados organismos zooplanctônicos (Daphnia similis, Daphnia laevis e Ceriodaphnia silvestrii) e bentônicos (Chironomus xanthus). As folhas de E. grandis apresentaram maior rendimento de óleo essencial que as de E. urophylla, tendo sido identificado maior número de substâncias nas folhas de E. urophylla. No caso dos extratos o E. grandis apresentou maior rendimento dos extratos hexânicos, tanto na primeira como na segunda etapa de extração enquanto o E. urophylla apresentou maior rendimento de extrato etanólico. Verificou-se como principais compostos nos extratos de E. urophylla esteróides e triterpenos. Os resultados dos testes de toxicidade aguda realizados com a água de decomposição das duas espécies de eucaliptos mostraram efeito tóxico a Daphnia similis, D. laevis e C.silvestrii e Chironomus xanthus o qual, entretanto, diminuiu com o aumento do tempo de decomposição. Os óleos essenciais apresentaram efeito tóxico em todos os testes realizados com cladóceros (folhas da serapilheira, 30 e 60 dias), assim como os extratos hidroalcoólicos (menos polares) a Chironomus xanthus e aquosos (mais polares) à D. similis e D. laevis verificou-se, portanto, no presente estudo, que os compostos naturais presentes nas folhas de E. grandis e E. urophylla podem afetar a biota aquática, sendo importante o monitoramento de ambientes aquáticos circundados por monoculturas de Eucalyptus spp. / Based on the scarce knowledge of the effect caused by eucalyptus on aquatic biota and the intense plantation in the surroundings of innumerable lakes in the Valley of Rio Doce, the present study evaluated extraction, identification and toxic effect of natural compounds found in leaves of Eucalyptus grandis and E. urophylla nearby Palmeirinha and Ferruginha lagoons, respectively, through vapor dragging distillation, high resolution gas chromatography (HRGC), Infrared spectroscopy (IR) and ecotoxicological tests with leaves decomposition water (laboratory), essential oils, hydroalcoholic and aqueous extracts of litter leaves, and after 30 and 60 days in contact with the lagoons. For the toxicity tests, zooplanktonic (Daphnia similis, Daphnia laevis and Ceriodaphnia silvestrii) and benthic (Chironomus xanthus) organisms were used. The leaves of E. grandis showed higher outcome of essential oils compared to E. urophylla, being identified a higher number of substances in E. urophylla leaves. In the case of extracts, E. grandis showed higher outcome of hexanic extracts in the first and second steps of extractions, while E. urophylla presented higher outcome of ethanolic extracts. The main compounds found in E. urophylla extracts were steroids and triterpenes, and in E. grandis were saponins, steroids and triterpenes. The results of the acute ecotoxicological tests carried out with decomposition water of both eucalyptus species showed toxic effect to Daphnia similis, D. laevis, C. silvestrii and Chironomus xanthus, which, however, decreased with decomposition time. The essential oils, showed toxic effect in all tests performed with cladocerans (litter leaves, 30 and 60 days), as well as the hydroalcoholic extracts to Chironomus xanthus and aqueous to D. similis and D. laevis. Thus, it was verified, in the present study, that the natural compounds found in E. grandis and E urophylla leaves can affect the aquatic biota, being important the monitoring of aquatic environments surrounded by Eucalyptus monocultures.
2

Avaliação ecotoxicológica de compostos naturais produzidos por Eucalyptus grandis e Eucalyptus urophylla no Vale do Rio Doce, Minas Gerais / Ecotoxicological evaluation of natural compounds produced by Eucalyptus grandis and Eucalyptus urophylla in the Valley of Rio Doce, Minas Gerais State

Ana Cristina Zoratto 31 August 2007 (has links)
Tendo como base o escasso conhecimento dos efeitos causados por eucaliptos sobre a biota aquática e o intenso plantio em áreas de entorno de inúmeros lagos no Vale do rio Doce, o presente estudo avaliou a extração, identificação e os efeitos tóxicos dos compostos naturais presentes nas folhas de Eucalyptus grandis e E. urophylla das áreas de entorno das lagoas Palmeirinha e Ferruginha, respectivamente, através de destilação por arraste a vapor de água, cromatografia gasosa de alta resolução (CGC), análise por infravermelho e testes ecotoxicológicos com as águas de decomposição das folhas (laboratório), com os óleos essenciais, extratos hidroalcólicos e aquosos das folhas da serapilheira, 30 e 60 dias após contato com as lagoas. Nos testes de toxicidade foram utilizados organismos zooplanctônicos (Daphnia similis, Daphnia laevis e Ceriodaphnia silvestrii) e bentônicos (Chironomus xanthus). As folhas de E. grandis apresentaram maior rendimento de óleo essencial que as de E. urophylla, tendo sido identificado maior número de substâncias nas folhas de E. urophylla. No caso dos extratos o E. grandis apresentou maior rendimento dos extratos hexânicos, tanto na primeira como na segunda etapa de extração enquanto o E. urophylla apresentou maior rendimento de extrato etanólico. Verificou-se como principais compostos nos extratos de E. urophylla esteróides e triterpenos. Os resultados dos testes de toxicidade aguda realizados com a água de decomposição das duas espécies de eucaliptos mostraram efeito tóxico a Daphnia similis, D. laevis e C.silvestrii e Chironomus xanthus o qual, entretanto, diminuiu com o aumento do tempo de decomposição. Os óleos essenciais apresentaram efeito tóxico em todos os testes realizados com cladóceros (folhas da serapilheira, 30 e 60 dias), assim como os extratos hidroalcoólicos (menos polares) a Chironomus xanthus e aquosos (mais polares) à D. similis e D. laevis verificou-se, portanto, no presente estudo, que os compostos naturais presentes nas folhas de E. grandis e E. urophylla podem afetar a biota aquática, sendo importante o monitoramento de ambientes aquáticos circundados por monoculturas de Eucalyptus spp. / Based on the scarce knowledge of the effect caused by eucalyptus on aquatic biota and the intense plantation in the surroundings of innumerable lakes in the Valley of Rio Doce, the present study evaluated extraction, identification and toxic effect of natural compounds found in leaves of Eucalyptus grandis and E. urophylla nearby Palmeirinha and Ferruginha lagoons, respectively, through vapor dragging distillation, high resolution gas chromatography (HRGC), Infrared spectroscopy (IR) and ecotoxicological tests with leaves decomposition water (laboratory), essential oils, hydroalcoholic and aqueous extracts of litter leaves, and after 30 and 60 days in contact with the lagoons. For the toxicity tests, zooplanktonic (Daphnia similis, Daphnia laevis and Ceriodaphnia silvestrii) and benthic (Chironomus xanthus) organisms were used. The leaves of E. grandis showed higher outcome of essential oils compared to E. urophylla, being identified a higher number of substances in E. urophylla leaves. In the case of extracts, E. grandis showed higher outcome of hexanic extracts in the first and second steps of extractions, while E. urophylla presented higher outcome of ethanolic extracts. The main compounds found in E. urophylla extracts were steroids and triterpenes, and in E. grandis were saponins, steroids and triterpenes. The results of the acute ecotoxicological tests carried out with decomposition water of both eucalyptus species showed toxic effect to Daphnia similis, D. laevis, C. silvestrii and Chironomus xanthus, which, however, decreased with decomposition time. The essential oils, showed toxic effect in all tests performed with cladocerans (litter leaves, 30 and 60 days), as well as the hydroalcoholic extracts to Chironomus xanthus and aqueous to D. similis and D. laevis. Thus, it was verified, in the present study, that the natural compounds found in E. grandis and E urophylla leaves can affect the aquatic biota, being important the monitoring of aquatic environments surrounded by Eucalyptus monocultures.
3

Impact des éléments trace métalliques sur le milieu et apport de la cytométrie en flux dans l'étude du fonctionnement des lagunes de la décharge d'Etueffont (Territoire de Belfort, France) / Impact of the trace metal element on the environnment and the contribution of flow cytometry to the study of functioning of the lagoons discharge of Etuffont (Territory of Belfort, France

Al Ashoor, Ahmed Shaker 14 December 2016 (has links)
L’objectif de ce travail de thèse est d’évaluer le degré de contamination des différents compartiments du site de la décharge d’Étueffont à savoir : les lixiviats, les sédiments, l’eau souterraine, les poissons, les insectes et les microorganismes de la décharge d’Étueffont. Ce travail de recherche est structuré en neuf chapitres.Après une première partie (Part I) consacrée à une étude bibliographique, le deuxième chapitre (Part II) présente le site d’étude, c’est-à-dire l’installation de stockage de déchets non dangereux(ISDND) d’Étueffont. La troisième partie (Part III) est consacrée à l’analyse de la qualité des lixiviats dans les lagunes, les unités de stockage des déchets « Nouveau casier », « Sous casier », « Ancienne décharge », les ruisseaux du gros Pré et Mont Bonnet. La quatrième partie (Part IV) intitulée « Contamination métallique des sédiments du site de la décharge d’Étueffont », aborde l’étude de la variation spatiotemporelle des éléments traces métalliques au niveau des lixiviats et des sédiments dans les quatre lagunes du site de la décharge d’Étueffont. Afin de déterminer le degré de contamination métallique des lixiviats et des sédiments, nous avons procédé à un suivi de certains éléments localisés en amont, au milieu et en aval de chaque lagune avec un pas d’échantillonnage trimestriel entre octobre 2013 et avril 2016. La cinquième partie (Part V), complémentaire du chapitre précédent, définit plus précisément la distribution spatiale du panache à travers l’analyse de la qualité de l’eau souterraine au moyen de piézomètres. La sixième partie (Part VI) concerne les effets des métaux lourds sur les échanges gazeux et la fluorescence des chlorophylles chez (Typha latifolia). Le septième chapitre (Part VII) est consacré à l’étude des microorganismes de la décharge d’Etueffont : apport de la cytométrie en flux. Dans le huitième chapitre (Part VIII), nous aborderons l’étude de la bioaccumulation des éléments traces métalliques dans le Chironome Chironomus riparius. La dernière partie (Part IX) intitulée « Étude de la bioaccumulation des éléments traces métalliques au niveau des différents organes du gardon Rutilus rutilus», aborde l’étude de la bioaccumulation des éléments traces métalliques au niveau de différents organes (muscle, foie, arêtes et branchies). / The objective of this thesis work is to estimate the contamination level in the various compartments of the Étueffont discharge site namely: leachates, sediments, groundwater, fishes and insects. The microorganisms (< 10 µm) of the Étueffont discharge of were investigated at the single cell level by flow cytometry. This research work is structured in nine chapters.The first part (Part I), is dedicated to a literature review. Part II presents the study site, the storage of non-hazardous waste (ISDND) at Étueffont. Part III is dedicated to the analysis of leachate quality in lagoons, NC, SC, AD, MB and GP. Part IV addresses "Metal Sediment Contamination of Étueffont discharge site" It concerns the study of spatial and temporal variation of trace metals in leachate and sediment in the four lagoons landfill site of Étueffont. To determine the metal contamination level in leachate and sediment, we conducted follow-elements located upstream, middle and downstream in each lagoon with quarterly sampling between October 2013 and April 2016. Part V complements the previous chapter, by specifically defining the spatial distribution of the plume through the quality analysis of the piezometer groundwater. Part VI addresses the heavy metals impacts on gas exchange and chlorophyll fluorescence in (Typha latifolia). Part VII is dedicated to the microorganisms (<10 µm) investigation in the Étueffont discharge: by using flow cytometry. In the (Part VIII), we addressed the study of bioaccumulation of trace metallic elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd and Pb) in insect Chironomus riparius. Part IX entitled "Study bioaccumulation of trace metals in the various organs of roach Rutilus rutilus" concerns bioaccumulation of trace metals in different organs (muscle, liver, bones and gills) of this fish.

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