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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.
231

Tolerância aos metais pesados chumbo e zinco e potencial fitorremediador de mudas de espécies arbóreas / Tolerance to the heavy metals lend and zinc and phytoremediation potential of seedlings of tree species

Souza, Sarah Caroline Ribeiro, 1986-, Andrade, Sara Adrián López de, 1971- 15 August 2018 (has links)
Orientadores: Marlene Aparecida Schiavinato, Sara Adrian Lopez de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-15T21:26:06Z (GMT). No. of bitstreams: 1 Souza_SarahCarolineRibeiro_M.pdf: 990180 bytes, checksum: a52442f68f3a27dfa82cded6425db23c (MD5) Previous issue date: 2010 / Resumo: A contaminação do solo por metais pesados (MPs), causada por processos naturais ou atividade humana, é um dos mais graves problemas ambientais devido à persistência e alto poder de toxicidade dos MPs. Em ambientes contaminados por MPs, as plantas podem apresentar uma série de distúrbios fisiológicos e nutricionais. No entanto, algumas espécies de plantas são tolerantes aos MPs e essa tolerância tem sido selecionada durante a evolução, e envolve diversos mecanismos. A associação com fungos micorrízicos arbusculares (FMAs) pode reduzir os efeitos negativos do estresse induzido por altas concentrações de metais sobre a planta hospedeira. Considerando a existência de plantas tolerantes, a fitorremediação, especialmente com espécies arbóreas, aparece como uma estratégia eficiente para a reabilitação de áreas contaminadas com MPs, uma vez que essas espécies imobilizam os metais absorvidos por mais tempo em seus tecidos. Assim, este estudo teve como objetivos: avaliar a tolerância, o acúmulo e a distribuição dos MPs, Pb e Zn, em três espécies de leguminosas nas diferentes partes das plantas; avaliar a influência destes metais na colonização micorrízica e na fixação biológica de nitrogênio e avaliar o potencial fitorremediador de cada espécie. Foram realizados dois experimentos, um com Pb e outro com Zn, com delineamento experimental totalmente casualizado e em esquema fatorial 3 x 4. Os tratamentos consistiram em três espécies de leguminosas arbóreas Mimosa caesalpiniaefolia (sansão-do-campo), Erythrina speciosa (eritrina-candelabro) e Schizolobium parahyba (guapuruvu) e quatro concentrações de metais, 0, 250, 500 e 1000 mg.dm-3 de Pb e 0, 200, 400 e 600 mg.dm-3 de Zn, adicionados ao solo na forma de acetato de chumbo e sulfato de zinco. Após aproximadamente 180 dias de cultivo as mudas foram coletadas. Determinaram-se altura, área foliar total, massa da matéria seca (MS) da parte aérea e raízes, número de nódulos e MS de nódulos das espécies que nodulam. Na espécie que não nodula, S. parahyba, foi feita a medição da raiz pivotante e o volume total de raízes. Foram feitas as determinações dos teores de Pb e Zn, dos nutrientes essenciais e calculado o índice de translocação (IT). Foram determinados o conteúdo de pigmentos fotossintéticos, a atividade da nitrogenase, aminoácidos livres, nitrato, amônia, peroxidação lipídica (MDA) e a taxa de colonização micorrízica. Os dados foram submetidos à análise de variância, análise de regressão e teste de Tukey. Verificou-se que altas concentrações de Zn adicionadas ao solo afetam mais significativamente o desenvolvimento de mudas de espécies arbóreas quando comparadas às concentrações de Pb utilizadas. Todas as espécies apresentam maiores concentrações de Zn e Pb nas raízes que agem como uma barreira à translocação dos MPs, considerado um mecanismo de fitoestabilização. O fato de serem espécies de leguminosas arbóreas de crescimento rápido, de fácil propagação, sistema radicular extenso e aliado ao fato de conseguirem absorver e concentrar os metais pesados Pb e Zn em suas raízes, sugere que estas espécies arbóreas analisadas podem ser potencias plantas fitorremediadoras de solos moderadamente contaminados, sendo que, para o Pb a espécie mais tolerante seria M. caesalpiniaefolia e para o Zn, a E. speciosa. / Abstract: Soil contamination by heavy metals (HM), caused by natural processes or human activity, is one of the most serious environmental problems due to their persistence and high toxicity potential. In HM contaminated environments, plants may present a series of physiological and nutritional disorders. However, some plant species are tolerant to HM and this tolerance has been selected during evolution. The mechanisms involved in plant tolerance to HM excess are diverse and varied. The association with arbuscular mycorrhizal fungi (AMF) can reduce the negative effects of stress induced by high concentrations of metals to the host plant. Considering the existence of tolerant plants, phytoremediation appears as na efficient strategy for the rehabilitation of areas contaminated with HM, especially using tree species, since these species immobilize absorbed metals for greater time periods in their tissues. Thus, this study aimed to evaluate the tolerance, accumulation and distribution of Pb and Zn in three species of leguminous trees, and further, to evaluate the influence of these metals in mycorrhizal colonization and nitrogen fixation and evaluate the phytoremediator potential of each of the studied species. For this purpose, two experiments were conducted, one with Pb and another with Zn, with a completely randomized experimental design in a factorial 3 x 4 scheme. The treatments consisted of three species of tree legumes Mimosa caesalpiniaefolia (sansão-do-campo), Erythrina speciosa (eritrinacandelabro) and Schizolobium parahyba (guapuruvu) and four concentrations of metal, 0, 250, 500 and 1000 mg.dm-3 Pb and 0, 200, 400 and 600 mg.dm-3 Zn added to soil in the form of lead acetate and zinc sulfate. Approximately 180 days after sowing, the seedlings were collected. We determined the height and total leaf area, the dry matter (DM) of shoots and roots, nodule number and nodule DM of nodulating species. In species that do not nodulate, S. parahyba, measurements were made of the tap root and root volume. Determinations were made of the levels of Pb and Zn as well as essential nutrients and the rate of translocation (IT) was calculated. The content of photosynthetic pigments was determined as well as photosynthesis, nitrogenase activity, amino acids, nitrate, ammonia and lipid peroxidation (MDA) and the rate of colonization was estimated. The data were subjected to analysis of variance, regression analysis and the Tukey test (5% significance). It was found that the higher concentrations of Zn added to soil affected the development of seedlings of the tree species studied more significantly than those of Pb. All species had higher Zn and Pb concentrations in their root, indicating this organ acts as a barrier for metal translocation to the shoots in these plants, considered a phytostabilization mechanism. The fact that these species are fast growing, easily propagated and have a extensive root system that can absorb and concentrate Pb and Zn, suggests that they have potential for use in phytoremediation of contaminated soils. / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal
232

Tratamento do lodo de resíduos de fossas e tanques sépticos em um sistema de alagado construído / Septic tanks and cesspools residues sludge treatment at a constructed wetlands system

Silva Junior, Édio Damásio da 13 November 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-23T16:36:45Z No. of bitstreams: 2 Dissertação - Édio Damásio da Silva Junior - 2013.pdf: 3273647 bytes, checksum: 8b91152a8caeed706b4e8d78ff9facc0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-23T18:07:43Z (GMT) No. of bitstreams: 2 Dissertação - Édio Damásio da Silva Junior - 2013.pdf: 3273647 bytes, checksum: 8b91152a8caeed706b4e8d78ff9facc0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-23T18:07:43Z (GMT). No. of bitstreams: 2 Dissertação - Édio Damásio da Silva Junior - 2013.pdf: 3273647 bytes, checksum: 8b91152a8caeed706b4e8d78ff9facc0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-11-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The use of individual systems for treatment and disposal of sewage (ISTDS) comes as an option to the lack of sanitation in many Brazilian regions, mainly in small settlements. However, the wastes generated in these systems represent another health problem, since it contains high levels of pathogens and organic load. These wastes, termed septic tanks and cesspools residues (STCR) must be treated before their disposal to the environment. Simple and low cost technologies, like the constructed wetlands systems (CW), should be developed and evaluated aiming its implementation in small population centers. This study aimed to evaluate the treatment, more specifically the cleaning and stabilization, of the sludge accumulated in a CW designed to treat STCR. Two tanks were constructed, dug into the ground and filled with overlapping layers of gravel and sand for application and treatment of the STCR. One of them was grown by the vegetal specie Vetiver Grass (Chrysopogon zizanioides) and the other one was used as a control treatment. The STCR were applied to the system by the exhaustion of clean-pit trucks. The system behaved in vertical downward subsurface flow, controlled by a fluid spilling system. Physical-chemical and microbiological analyses of the crude residue and sludge in treatment in both tanks were made. The STCR nutritional potential was characterized through the determination of total phosphorus, total, organic and ammonia nitrogen, nitrite and nitrate. Their pathogen load was characterized by counting total coliforms, Escherichia coli, Salmonella spp. and helminths viable eggs. In addition, were characterized the attributes pH, moisture, total, volatile and fixed solids. From the sludge accumulated on the surface of treatment beds they were evaluated its pathogen load, solids content and moisture. The results were compared with the established pursuant to resolution nº 375/2006, of the brazilian National Council for the Environment (CONAMA), to verify the possibility of the sludge use in agriculture. The crude residue characterization results, showed to be similar to those cited by the literature, with high concentrations of pathogens and nutrients and also, high dispersion of values. With STCR disposals, the sludge layer increased in both systems, with higher values for the CW (about 1.1 cm per month), because of their greater capacity to retain moisture. During the disposal phase, both tanks sludge remained with high values of pathogenic organisms. At the end of the applications, there has been considerable reduction of these values, suggesting that for a better sludge treatment should be a period of "rest" without applications. It was observed that after two months of "rest", the sludge from both tanks was framed in A Class, with potential use in agriculture, as standardizes the resolution nº 375/2006 of CONAMA. In general, the tank without plants showed greater speed in the process of cleaning the sludge than the CW, mainly due to the direct sunlight exposure. However, with respect to the stabilization process, the CW was better than the control tank. / A utilização de sistemas individuais de tratamento e disposição de esgoto (SITDE) constitui-se em opção à carência de saneamento básico em diversas regiões brasileiras, principalmente em pequenos núcleos populacionais. Todavia, os resíduos esgotados nestes sistemas representam novo problema sanitário, uma vez que contém elevados teores de organismos patogênicos e de carga orgânica. Estes resíduos, denominados de resíduos de fossas e tanques sépticos (RFTS), devem ser tratados antes de sua disposição no meio ambiente. Tecnologias simples e de baixos custos, como os sistemas de alagados construídos (SAC’s), devem ser desenvolvidas e pesquisadas visando sua implantação em pequenos núcleos populacionais. Este trabalho objetivou avaliar o tratamento, mais especificamente a higienização e estabilização, do lodo acumulado em um SAC projetado para tratamento de RFTS. Foram construídos dois tanques, escavados no solo e preenchidos com camadas sobrepostas de brita e areia para aplicação e tratamento dos RFTS. Um tanque foi cultivado com a espécie vegetal Capim Vetiver (Chrysopogon zizanioides) e o outro serviu de testemunha. Os RFTS foram aplicados através do esgotamento de caminhões limpa-fossa. O sistema comportou-se em fluxo subsuperficial vertical descendente, controlado por um sistema de extravazão de líquidos. Foram realizadas análises físico-químicas e microbiológicas do resíduo bruto e do lodo em tratamento de ambos os tanques. Caracterizou-se o potencial nutricional do RFTS por meio da determinação das concentrações de fósforo total, nitrogênio total, orgânico e amoniacal, nitrito e nitrato. A carga de patógenos foi obtida por meio da contagem de coliformes totais, Escherichia coli, Salmonella spp. e ovos viáveis de helmintos. Também foram caracterizados os atributos pH, umidade, sólidos totais, fixos e voláteis. Do lodo acumulado na superfície dos leitos de tratamento avaliaram-se a carga patógena, o teor de sólidos e a umidade. Os resultados foram comparados com o estabelecido pela resolução nº 375/2006, do Conselho Nacional de Meio Ambiente (CONAMA), para verificar sua potencialidade de uso agrícola. A caracterização do resíduo bruto apresentou dados similares à literatura, com elevadas concentrações de patógenos e nutrientes, além da alta dispersão de resultados. Com as disposições do RFTS, a camada de lodo aumentou em ambos os sistemas, com valores superiores para o SAC (cerca de 1,1 cm ao mês), em virtude de sua maior capacidade de retenção de umidade. Durante a fase de aplicação dos resíduos, o lodo de ambos os tanques permaneceu com altos valores de organismos patógenos. Ao cessar as aplicações, houve considerável redução destes valores, sugerindo que para melhor tratamento do lodo deve-se haver um período de “descanso”, sem aplicações. Observou-se que após um período de dois meses de “descanso”, o lodo de ambos os tanques foi enquadrado na classe A, com possibilidade de uso na agricultura, conforme normatiza o CONAMA. De forma geral, o tanque sem plantas apresentou maior rapidez no processo de higienização do lodo do que no SAC, principalmente em função da exposição solar direta. Entretanto, no que tange ao processo de estabilização, o SAC foi superior ao tanque controle.
233

Disposição de efluente de tratamento de esgoto industrial em solo vegetado com bambu / Industrial sewage treatment effluent disposal in soil vegetated with bamboo

MENDONÇA, Eurivan Alves 31 August 2010 (has links)
Made available in DSpace on 2014-07-29T15:01:44Z (GMT). No. of bitstreams: 1 Dissertacao Eurivan A Mendonca 2010.pdf: 356252 bytes, checksum: 182f4d4d579221f0db2469404dd75fd2 (MD5) Previous issue date: 2010-08-31 / This study aimed to evaluate the efficiency of the bamboo species Guadua angustifolia Kunth, Guadua chacoensis and Dendrocalamus giganteus Munro in the treatment of the Senador Canedo Industrial District Sewer Treatment effluent. It was analyzed diary effluent slides of 176.8, 212.2, 247.6 and 353.7 mm applied in individual 200 L drums filled with regional soil (oxisoil) and vegetated with bamboo. Drums without plants served as control. The effluent treated by the containers was analyzed for biochemical oxygen demand (BOD), dissolved oxygen, chemical oxygen demand (COD), apparent color, pH, ammonium nitrogen, phosphates, turbidity, chlorides, hardness, electrical conductivity, total solids, dissolved total solids, volatile total solids, fixed total solids and coliforms, during a five month period. The results were analyzed by Statistical Analysis System Program (SAS) through F test and Tukey-Kramer test (5% of probability). Treatment using bamboo were more efficient than control in removing BOD, COD, pH, dissolved oxygen, apparent color, total solids, fixed solids, coliforms, chlorides, turbidity, electrical conductivity, phosphates and ammonium nitrogen. Among vegetated drums, bamboos of Guadua gender were more efficient in removing BOD, COD, coliforms and volatile solids than units with D. giganteus. Application rates had no significant influence on treatment efficiencies. It was also evaluated the bamboo species under field conditions, submitted to a diary effluent slide of 353.7 mm for a period of one year. Samples of groundwater were collected to verify some resultant contamination from the effluent application. It wasn t observed groundwater contamination by applying effluent at soil vegetated with bamboo. / Este estudo objetivou avaliar a eficiência das espécies de bambu Guadua angustifolia Kunth, Guadua chacoensis e Dendrocalamus giganteus Munro, no tratamento do efluente da estação de tratamento de esgotos do Distrito Industrial de Senador Canedo, GO. Analisou-se a aplicação das lâminas diárias de efluente de 176,8; 212,2; 247,6 e 353,7 mm em tambores individuais de 200 Litros preenchidos com solo da região (latossolo vermelho distrófico) e vegetados com bambu. Tambores sem plantas serviram de testemunhas. O efluente tratado nos tambores foi analisado quanto à demanda bioquímica de oxigênio (DBO), oxigênio dissolvido, demanda química de oxigênio (DQO), cor aparente, pH, nitrogênio amoniacal, fosfatos, turbidez, cloretos, dureza, condutividade elétrica, sólidos totais, sólidos totais dissolvidos, sólidos totais voláteis, sólidos totais fixos e coliformes termotolerantes, por um período de cinco meses. Os resultados foram submetidos aos testes F e de Tukey-Kramer (5% de probabilidade). Os tratamentos com bambu foram mais eficientes na remoção dos parâmetros DBO, DQO, pH, oxigênio dissolvido, cor, sólidos totais, sólidos fixos, coliformes termotolerantes, cloretos, turbidez, condutividade elétrica, fosfatos e nitrogênio amoniacal que a testemunha sem planta. Os bambus do gênero Guadua foram mais eficientes na remoção de DBO, DQO, coliformes termotolerantes e sólidos voláteis que o tratamento com D. giganteus. Observou-se que as taxas de aplicação não tiveram influência significativa nas eficiências do tratamento. Também se avaliaram as espécies de bambu em condições de campo, submetidas à aplicação de uma lâmina diária de 353,7 mm de efluente por um período de um ano. Coletaram-se amostras da água do lençol freático com a finalidade de verificar a ocorrência de contaminação decorrente da aplicação do efluente. Não foi observada contaminação do lençol freático pela aplicação do efluente no solo vegetado com bambu.
234

Tratamento de esgoto sanitário em sistemas alagados construídos utilizando Typha angustifolia e Phragmites australis / Sanitary sewer treatment in constructed wetlands system using Typha angustifolia and Phragmites australis

ABRANTES, Lorena Lemes Martins 28 August 2009 (has links)
Made available in DSpace on 2014-07-29T15:01:49Z (GMT). No. of bitstreams: 1 Dissertacao Lorena L M Abrantes.pdf: 4341681 bytes, checksum: 30126c561a517a7154d7108de137e004 (MD5) Previous issue date: 2009-08-28 / This study aimed to assess the efficiency of two vegetal species in the treatment of the sanitary sewer, in constructed wetlands system. Specifically, it aimed to evaluate the efficiency of the species Typha angustifolia (narrow-leaf cattail) and Phragmites australis (common reed), in their possible combinations, in the treatment of the sanitary sewer, in a constructed wetlands system, of vertical subsuperficial flux, with two flux directions (ascendant and descendant), related to the attributes: organic material, apparent color, ammonium nitrogen, phosphate, turbidity, chlorides, hardness, electrical conductivity, solids and thermotolerant coliforms. The experiment was conducted in the Researching Station in Sewer Treatment with Plants RSSTP (UFG), located in the Sewer Treatment Station (STS) Samambaia, in Goiânia, Goiás State, Brazil. The experimental unit has twenty four modules, grouped sequences of two modules (initial and final modules). Raw sewage which comes from the initial part of the ETE facultative pond was pumped into the deep of the treatment initial modules, filled up with substrate layers (in the deep filled up with rocks category number 3, followed by rocks category number 1, washed sand, and again rocks category number 1) and planted with cattail or reed. After going up by the vegetated substrate (ascendant vertical flux) the sewer was drained and conducted to the final treatment modules equally filled up and vegetated with one of the species, although being applied in the surface and drained by the deep (vertical descendant flux). The tax of sewer application was of 80 L.m-2dia-1, corresponding to a treatment area of 2 m2 per inhabitant. A year after the system implementation, during the period of 6 months, sewer samples were collected after passing through the flux sequences, each one with the combination of the two vegetal species, for the evaluation of the sewer attributes and calculation of the efficiency in the treatment. The results were analyzed by the Statistical Analysis System (SAS program), being used the tests F and the Tukey Kramer, considering 5% of probability. There were no meaningful differences in the efficiency of the treatments in the removal of the attributes: biochemical oxygen demand, chemical oxygen demand, ammonium nitrogen, phosphate, thermotolerant coliforms, chlorides, hardness, dissolved total solids and volatile total solids. The cattail was more efficient in the apparent color removal and turbidity. The reed presented more efficiency in the total solids removal. The position of the plant in the module sequence did not influence the apparent color and turbidity removals. The reed in the final module increased the removal of the attributes total solids and fixed total solids. It´s possible to verify that the technology of sewer treatment by using plants is efficient, since the species cattail and reed in the adopted system, provided results with removals higher 60% for the of the attributes: biochemical oxygen demand, chemical oxygen demand, apparent color, ammonium nitrogen, phosphate, thermotolerant coliforms and turbidity. / O presente estudo teve como objetivo avaliar a eficiência de duas espécies vegetais no tratamento do esgoto sanitário, em um sistema de alagados construídos. Especificamente, objetivou-se avaliar a eficiência das espécies Typha angustifolia (Taboa) e Phragmites australis (Caniço), em suas combinações possíveis, no tratamento de esgoto sanitário, em um sistema de alagados construídos, de fluxo subsuperficial vertical, com dois sentidos de fluxo (ascendente e descendente), concernente aos atributos: matéria orgânica, cor aparente, nitrogênio amoniacal, fosfato, turbidez, cloretos, dureza, condutividade elétrica, sólidos e coliformes termotolerantes. O experimento foi conduzido na Estação de Pesquisas em Tratamento de Esgotos com Plantas Eptep (UFG), localizada na Estação de Tratamento de Esgotos (ETE) Samambaia, em Goiânia, GO. A unidade experimental possui vinte quatro módulos, agrupados em sequências de dois módulos (módulos iniciais e finais). Esgoto sanitário bruto proveniente da parte inicial da lagoa facultativa da ETE foi bombeado no fundo de módulos iniciais de tratamento preenchidos com camadas sobrepostas de substrato (no fundo com brita número 3, na sequência brita número 1, areia lavada e novamente brita número 1) e plantados com taboa ou caniço. Após subir pelo substrato vegetado (fluxo vertical ascendente) o esgoto era drenado e conduzido aos módulos finais de tratamento, igualmente preenchidos e vegetados com uma das espécies, todavia sendo aplicado na superfície e drenado pelo fundo (fluxo vertical descendente). A taxa de aplicação de esgoto foi de 80 L.m-2dia-1, correspondendo a uma área de estação de tratamento de 2 m2 por habitante. Um ano após a implantação do sistema, por um período de seis meses, amostras do esgoto foram coletadas após passar pelas sequências de fluxo, cada uma com uma combinação das duas espécies vegetais, para avaliação dos teores de atributos do esgoto e cálculo da eficiência do tratamento. Os resultados foram analisados pelo programa Statistical Analysis System (SAS), realizando-se os testes F e de Tukey Kramer, a 5% de probabilidade. Não houve diferença significativa entre as eficiências dos tratamentos na remoção dos atributos: demanda bioquímica de oxigênio, demanda química de oxigênio, nitrogênio amoniacal, fosfatos, coliformes termotolerantes, cloretos, dureza, sólidos totais dissolvidos e sólidos totais voláteis. A taboa foi mais eficiente na remoção da cor aparente e da turbidez. Já o caniço apresentou uma eficiência maior na remoção de sólidos totais. A posição da planta na sequência de módulos não influenciou na remoção da cor aparente e da turbidez. O caniço no módulo final influenciou positivamente na remoção dos atributos sólidos totais e sólidos totais fixos. Verifica-se que a tecnologia de tratamento de esgoto por plantas é eficiente, uma vez que as espécies taboa e caniço no sistema de fluxo subsuperficial vertical ora adotado proporcionaram resultados com remoções superiores a 60% para os atributos demanda bioquímica de oxigênio, demanda química de oxigênio, cor aparente, nitrogênio amoniacal, fosfatos, coliformes termotolerantes e turbidez.
235

Prospecção de plantas fitorremediadoras em solos contaminados por metais pesados

Silva, José Felício da 30 November 2012 (has links)
Made available in DSpace on 2015-04-20T12:31:17Z (GMT). No. of bitstreams: 1 jose felicio.pdf: 2154157 bytes, checksum: 92f1a3fbff21731380d6fdf59ce09e91 (MD5) Previous issue date: 2012-11-30 / Phytoremediation uses plants for remediating soils and aquatic system contaminated by inorganic and organic substances. Their results are satisfactory and demonstrate that certain plant species having high genetic potential for removing, degrading, metabolizing or immobilizing a lot of contaminants, such as heavy metal, petroleum, domestic and industrial sewage, etc. Despite promising the phytoremediation has been find problems in discover new plants with the ability for remediating contaminated environments. This study purpose a survey prospective for identifying plants into Manaus Industrial Pole (MIP) region that can accumulate high contents of heavy metals. The following species: Vismia guianensis (Aubl.) Choise, Diplasia karataefolia, Vismia japurensis Annona, Alibertia edulis A. Rich, Poaceae (Capim colonião), Lantana camara L., Araceae and Diffenbachia picta Schott were collected in three forest patches near streams of the MIP. The choiced plants were supported on the remarkable contamination that the streams have been submitted. Soil samples of forest patch were also collected and their physical and chemical proprieties determined by EMBRAPA methodologies. The Plants leaves were separated, digested by concentrated HNO3 at 60 oC, and the contents of Cu, Fe, Zn, Cd, Mn, Pb, Co and Ni determined by flame atomic absorption spectrometry. Findings show that all studied plants are capables of uptake high contents of heavy metals. As a result we can affirm that Vismia guianensis (Aubl.) Choise, Diplasia karataefolia, Vismia japurensis Annona, Alibertia edulis A. Rich, Poaceae (Capim colonião), Lantana camara L., Araceae and Diffenbachia picta Schott are potentially phytoremediators. / A Fitorremediação utiliza plantas para remediar solos e sistemas aquáticos contaminados por substâncias orgânicas e inorgânicas. Seus resultados são satisfatórios e demonstram que certas espécies de plantas com alto potencial genético podem remover, degradar, metabolizar ou imobilizar uma série de contaminantes, como metais pesados, petróleo, esgoto doméstico e industrial, etc. Apesar de promissora a fitorremediação tem encontrado problemas em descobrir novas plantas com capacidade para remediação de ambientes contaminados. O propósito deste estudo prospectivo é a identificação de plantas na região do Pólo Industrial de Manaus (PIM), que possam acumular altos teores de metais pesados. As seguintes espécies: Vismia guianensis (Aubl.) Choise, Diplasia karataefolia, Vismia japurensis, Annona, Alibertia edulis A. Rich, Poaceae (Capim colonião), Lantana camara L., Araceae e Diffenbachia picta Schott, foram coletadas em três fragmentos florestais, nas margens de igarapés do PIM. As plantas escolhidas foram submetidas a elevados níveis de contaminação provenientes da poluição dos igarapés. Amostras de solo dos fragmentos florestais foram coletadas e suas propriedades físicas e químicas determinadas por metodologias da EMBRAPA. As folhas de plantas foram separadas, digeridas com HNO3 concentrado a 60 ° C, e o conteúdo de Zn, Fe, Mn, Cu, Co, Cd, Pb e Ni, determinado por espectrometria de absorção atómica. Os resultados mostram que todas as plantas estudadas são capazes absorverem níveis elevados de metais pesados em suas folhas. Como resultado, podemos afirmar que Vismia guianensis (Aubl.) Choise, Diplasia karataefolia, Vismia japurensis, Annona, Alibertia edulis A. Rich, Poaceae (Capim colonião), Lantana camara L., Araceae e Diffenbachia picta Schott são potencialmente fitorremediadoras.
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Macrófitas aquáticas e efluente de cervejaria: dinâmica e perspectivas / Aquatic macrophytes and brewery wastewater: dynamics and perspectives

Gonzalez, Aline Costa 03 July 2015 (has links)
Made available in DSpace on 2017-07-10T18:01:53Z (GMT). No. of bitstreams: 1 Aline Costa Gonzalez.pdf: 254133 bytes, checksum: 055398796e1b2193f444144c41185e0f (MD5) Previous issue date: 2015-07-03 / In the last decades, environmental problems have become more serious and frequent, especially due to the expansion of industrial activities. Those occupy the second position on total water consumption and generate alteration in its quality because of pollutant release, causing eutrophication and pollution of water resources. Therefore, it is necessary to raise sustainable technologies that praise environmental conservation and the use of natural resources, making possible a more efficient use of water, reducing costs and saving it to different sectors. Thus, having in mind the several benefits as the improvement of water quality, better distribution and rationing of it, allied to water waste treatment required by environmental control agencies, this research aimed to evaluate and to compare the efficiency of two aquatic macrophyte species on the removal of polluting substances from brewery wastewater, in order to provide an alternative technology, which is also clean, efficient, aesthetic and with low energetic costs. An experimental system was carried out in mesocosms with two treatments composed by the species Salvinia molesta and Limnobium laevigatum, with four replicates each one. Each mesocosm was filled with 80 liters of brewery wastewater 25% diluted and 40g of macrophytes. The experiment was conducted during 28 days and the wastewater was weekly sampled to measure limnological characterizes in laboratory. Moreover, macrophytes were weekly weighed, and leaf area was measured to monitor the biomass development. It was possible to observe that both macrophytes species used in this biological treatment were able to clarify wastewater, to eliminate great portion of smell and to significantly reduce the pollutant charge, which parameters, at some point, were in conformity with Brazilian legislation, except for phosphorus. It was also possible to notice that in the first week the removal percentage was quick, but in the second and the third week the variable concentrations analyzed practically were not altered e and started to raise, demonstrating that the macrophytes reached their tolerance limit. Hence, trying to reduce even more the analyzed parameters concentrations, especially for phosphorus, it is suggested that the plants should be replaced in that period. It could be concluded that these macrophytes species have a great potential on pollutant removal and biomass production. So, they are recommendable in biological technologies for the treatment of wastewater, making possible the reuse of the treated water and the biomass. / Nas últimas décadas os problemas ambientais têm se tornado cada vez mais críticos e frequentes, principalmente devido à expansão das atividades industriais. Estas ocupam a segunda posição no consumo total de água e geram alterações em sua qualidade, pela liberação de poluentes, causando eutrofização e poluição dos recursos hídricos. Assim, é necessário promover tecnologias sustentáveis que preconizem a conservação ambiental e o uso dos recursos naturais, possibilitando utilizar a água de maneira mais eficiente, reduzindo os custos e poupando-a para outros setores. Dessa forma, tendo em vista os vários benefícios, como a melhoria da qualidade da água, melhor distribuição e racionalização desta, aliadas a exigência do tratamento de efluente pelos órgãos de controle ambiental, a pesquisa teve como objetivo avaliar e comparar a eficiência de duas espécies de macrófitas, na remoção de substâncias poluidoras de efluente de cervejaria, no intuito de proporcionar uma alternativa tecnológica limpa, eficiente, estética e de baixos custos energéticos. Foi montado um sistema experimental em mesocosmos com dois tratamentos compostos pelas espécies Salvinia molesta e Limnobium laevigatum em quatro réplicas. Em cada mesocosmo foi acondicionado 80 litros de efluente bruto diluído a 25% e 40g de macrófitas. O experimento foi conduzido por 28 dias, com coletas semanais do efluente para mensuração das variáveis limnológicas em laboratório. Além disso, as macrófitas foram pesadas semanalmente e a área foliar foi mensurada a fim de monitorar o desenvolvimento da biomassa. Foi possível observar que ambas as espécies de macrófitas utilizadas no tratamento biológico, clarificaram a água, praticamente eliminaram o odor e reduziram significativamente as cargas poluentes, cujos parâmetros, em algum momento do experimento ficaram dentro dos valores permitidos pela legislação brasileira vigente, exceto o fósforo. Foi possível observar também que na primeira semana a porcentagem de remoção foi rápida, porém entre a segunda e terceira semana, as concentrações das variáveis analisadas no efluente, praticamente não alteraram ou começaram a se elevar, mostrando que as macrófitas chegaram em seu limite de tolerância. Portanto, buscando diminuir ainda mais as concentrações dos parâmetros analisados, em especial do fósforo, sugere-se que faça a troca das plantas neste período. Concluiu-se que estas macrófitas possuem grande potencial na remoção de poluentes, além de obterem boa produção de biomassa, sendo recomendável a utilização das mesmas em tecnologias biológicas para tratamento de efluente, possibilitando a reutilização da água tratada e a biomassa.
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Environmentální účinky radiofarmak obsahujících 223 Ra / Environmental Effects of 223-Ra Radiopharmaceuticals

Krmelová, Tereza January 2016 (has links)
Title: Environmental Effects of 223 Ra Radiopharmaceuticals Author: Tereza Krmelová Branch: Environmental chemistry Type of thesis: Diploma thesis Advisor: Doc. Ing. Stanislav Smrček, CSc Abstract: In thesis was studied the possibility of extracting the nanoparticles of titanium dioxide or hydroxyapatite with bounded 223 Ra by root system of tested plant species Avena sativa and Zea mays as a model for phytoremediation technologies. The thesis obtains data to assess the potential of residues radioactivity and nanomaterials entering the food chain. There was also verified an experiment of 223 Ra phytoextraction, in the form of nitrate, in effects on addition of EDTA, which was conducted in Bachelor thesis. This experiment was repeated because of its results, which were inconsistent with generally described phytoextraction efficiency improvements after adding the complexing agents. In this work was primary studied translocation of radioactive material from the root to shoot. Experimentally was confirmed the extraction of nanoparticles with bounded 223 Ra and translocation into shoot. In the case of Avena sativa, capturing of nanoparticles hydroxyapatite with bounded 223 Ra was 53 % of which 88 % of activity was recovered in roots and 12 % in shoots. Capturing nanoparticles of titanium dioxide with bounded 223...
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Phytoremediation of heavy metal and PAH contaminated soil : effects of bacterial inoculation on PAH removal, metal speciation, bioavailability and uptake by Sedum alfredii

Li, Wai Chin 01 January 2007 (has links)
No description available.
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Phytoremediation of Nitrous Oxide: Expression of Nitrous Oxide Reductase from Pseudomonas Stutzeri in Transgenic Plants and Activity thereof

Wan, Shen January 2012 (has links)
As the third most important greenhouse gas, nitrous oxide (N2O) is a stable greenhouse gas and also plays a significant role in stratospheric ozone destruction. The primary anthropogenic source of N2O stems from the use of nitrogen in agriculture, with soils being the major contributors. Currently, the annual N2O emissions from this “soil–microbe-plant” system is more than 2.6 Tg (one Tg equals a million metric tons) of N2O-N globally. My doctoral studies aimed to explore innovative strategies for N2O mitigation, in the context of environmental microbiology’s potential contribution to alleviating global warming. The bacterial enzyme nitrous oxide reductase (N2OR), naturally found in some soils, is the only known enzyme capable of catalyzing the final step of the denitrification pathway, conversion of N2O to N2. Therefore, to “scrub” or reduce N2O emissions, bacterial N2OR was heterologously expressed inside the leaves and roots of transgenic plants. Others had previously shown that the functional assembly of the catalytic centres (CuZ) of N2OR is lacking when only nosZ is expressed in other bacterial hosts. There, coexpression of nosZ with nosD, nosF and nosY was found to be necessary for production of the catalytically active holoenzyme. I have generated transgenic tobacco plants expressing the nosZ gene, as well as tobacco plants in which the other four nos genes were coexpressed. More than 100 transgenic tobacco lines, expressing nosZ and nosFLZDY under the control of rolD promoter and d35S promoter, have been analyzed by PCR, RT-PCR and Western blot. The activity of N2OR expressed in transgenic plants, analyzed with the methyl viologen-linked enzyme assay, showed detectable N2O reducing activity. The N2O-reducing patterns observed were similar to that of the positive control purified bacterial N2OR. The data indicated that expressing bacterial N2OR heterologously in plants, without the expression of the accessory Nos proteins, could convert N2O into inert N2. This suggests that atmospheric phytoremediation of N2O by plants harbouring N2OR could be invaluable in efforts to reduce emissions from crop production fields.
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Réponses physiologiques, antioxydantes et métabolomiques de Thellungiella salsuginea et Arabidopsis thaliana à l'interaction salinité modérée-phénanthrène : application à la phytoremédiation des HAPs par les halophytes / Physiological, antioxidant and metabolomic responses of Thellungiella salsuginea and Arabidopsis thaliana to moderate salinity-phenanthrene interaction : application to phytoremediation of PAHs by halophytes

Moez, Shiri 04 July 2014 (has links)
La pollution environnementale constitue un problème majeur pour les écosystèmes naturels et la santé publique. Récemment, la phytoremédiation a émergé comme une stratégie innovante, écologique et à faible coût. Elle consiste à utiliser les capacités des plantes à stocker ou/et à dégrader les polluants. Dans cette étude, des analyses physiologiques, biochimiques et métabolomiques, ont permis de montrer que les halophytes, une catégorie des plantes extrêmophiles, présentent une grande capacité à remédier la pollution engendrée par les Hydrocarbures Aromatiques Polycycliques (HAPs). D'autre part, la salinité modérée améliore leur capacité phytoremédiatrice. Ces résultats apportent de nouvelles données pouvant contribuer à l'amélioration de cette stratégie. / Halopytes, plants naturally adapted to high salt concentrations, have no clear definition, yet. Their cross-tolerance to abiotic stresses was reviewed in this work at the physiological, biochemical, and molecular levels, with a special emphasis on the mechanisms involved in their cross-tolerance to salinity and organic pollutants that could allow them a higher potential of xenobiotic phytoremediation as compared to glycophytes. In our experimental part, we compared in a first step some physiological and antioxidant responses to phenanthrene as well as its accumulation in the two related model plants Arabidopsis thaliana (glycophyte) and Thellungiella salsuginea (halophyte).In a second step, we investigated the effects of moderate salinity on the responses of the two species to phenanthrene considered as model Polycyclic Aromatic Hydrocarbon (PAH) molecule. Obtained results showed an improvement of phenanthrene-induced responses in the two plants, the effect being more marked in the halophyte. This observation was particularly related to higher antioxidant activities and the induction of more adapted metabolism as several accumulated metabolites are known to be involved in signaling and osmotic adjustment processes. In a final step, we studied the potential of the halophyte Cakile maritima to remediate an inert sand (to avoid the degradation of the pollutant by microorganisms or their interaction with the plant) highly contaminated with phenanthrene.

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