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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.
171

Phytoremédiation des organochlorés. Etude mécanistique et fonctionnelle des capacités épuratrices du système plante-rhizosphère / Organochlorines phytoremediation. Mechanistic and functional studies of the system plant rhizosphere purifying capacitis.

San Miguel, Angélique 01 December 2011 (has links)
Les organochlorés (OCs) -molécules utilisées dans des procédés industriels et en applications agricoles dont la plupart sont interdites d'utilisation de nos jours- sont considérés comme des polluants très persistants représentant une menace pour les eaux de surfaces et souterraines, le sol et l'atmosphère. Des méthodes alternatives de décontamination de sites pollués aux OCs sont développées utilisant des technologies in situ d'écoremédiation. L'objectif du projet de thèse est d'étudier les capacités de phytoremédiation des OCs par deux plantes modèles, Zea mays et Phragmites australis. Les OCs choisis dans cette étude sont, le lindane (γHCH), le monochlorobenzène (MCB), le 1,4-dichlorobenzène (DCB) et le 1,2,4-trichlorobenzène (TCB). Notre approche a été de considérer l'impact sur les fonctions physiologiques des plantes de chaque OC en mono-exposition, puis de comparer ces mêmes réponses physiologiques en multi-exposition. Ce travail a permis de mettre en évidence un effet synergique de l'action du mélange des OCs. Toutefois, Z. mays et P. australis tolérent des concentrations OCs largement supérieures aux concentrations environnementales mesurées in situ. La phytoextraction des OCs a été démontrée par nos expériences en conditions contrôlées et en utilisant des molécules 14C-OCs. Les OCs sont majoritairement bioconcentrés au niveau des organes souterrains des plantes. Enfin, cette étude montre une adaptation de la microflore bactérienne de la rhizosphère en présence d'un gradient d'exposition aux OCs (multi-exposition). Les approches d'isolement et d'études d'empreintes moléculaires (ARNr 16S, SSCP, pyroséquançage 454) ont permis de détecter des souches potentiellement capables d'assurer une rhizodégradation des OCs. / Organochlorines (OCs) -molecules used in industrial processes and in agricultural applications which are prohibited from use nowadays- are classified as very persistent pollutants and show an environmental risk for surface water and groundwater, soil and atmosphere. To restore polluted sites, alternative methods are developed using ecoremediation technologies in situ. The aim of this thesis is to study the OCs phytoremediation capacities using two model plants, Zea mays and Phragmites australis. OCs slected for this work are, lindane (γHCH), monochlorobenzene (MCB), 1,4-dichlorobenzene (DCB) and 1,2,4-trichlorobenzene (TCB). The work strategy was to compare the effects on plant physiological functions when plants were exposed to each OC (mono-exposure) and to a mixture of all OCs (multi-exposure). This study highlighted a synergistic effect of the OCs mixture. However, Z. mays and P. australis were able to tolerate OCs mixture concentrations much higher than the environmental concentrations measured in situ. The OCs phytoextraction was demonstrated by our experiments under controlled conditions and using 14C-OCs molecules. OCs were mostly bioconcentrated in the underground parts of the plants. This study also demonstrated an adaptation of the rhizospheric bacterial microflora under a gradient of OCs exposures (multi-exposure). The techniques used (16S rRNA, SSCP, 454 pyrosequencing) held to the detection of strains potentially able to provide OC-rhizodegradation.
172

INFLUÊNCIA DE DIFERENTES CONCENTRAÇÕES DE NÍQUEL SOBRE O CRESCIMENTO E DESENVOLVIMENTO INICIAL DE GUAZUMA ULMIFOLIA LAM. (MALVACEAE, MALVALES).

Amado, Sarah 09 December 2015 (has links)
Made available in DSpace on 2016-08-10T10:54:53Z (GMT). No. of bitstreams: 1 SARAH AMADO.pdf: 2510363 bytes, checksum: c922e69e7e10e882a313e3fde348878c (MD5) Previous issue date: 2015-12-09 / The irregular dumping of heavy metals in the environment is caused, most of the times, by mining activities. Among the metals processed by mining activities is the nickel, a chemical element which presents a great toxicity to fauna, flora and human beings. Aiming to avoid health damage to live beings caused by nickel, there is as an alternative: the soil decontamination through phytoremediation, technology, which uses plant species resistant to heavy metals and is able to extract, degrade, contain and or immobilize them in the soil. Therefore, this research goal was to evaluate the germination, growing and initial development of seeds and young plants of the Guazuma ulmifolia Lam species under different nickel concentrations, aiming its use in restoration of areas contaminated by this metal. So, the experiments were divided into two phases. In the first one, the G. ulmifolia seeds were distributed into six treatments with Ni (NO3)2 [C (0 mg.L-1), T1 (20 mg.L-1), T2 (40 mg.L-1), T3 (60 mg.L-1), T4 (80 mg.L-1) e T5 (100 mg.L-1)], with four repetitions per treatment and 20 seeds per repetition. In the second phase, it was used G. ulmifolia seedlings distributed into five treatments with Ni (NO3)2 [C (0 mg.L-1), T1 (100 mg.L-1), T2 (200 mg.L-1), T3 (400 mg.L-1) e T4 (600 mg.L-1)], each treatment was established with seven repetitions and each repetition was considered to be one seedling into a plastic container containing 1000 cm³ of substrate. At the end of the experiments, the obtained data were analyzed through the ANOVA test followed by the Tukey s multiple comparison test. The statistics results showed no significance to the germination and significant to root length and mortality after the G. ulmifolia germination which makes difficult the use of direct planting of its seeds in phytoremediation programs. Related to the established patterns for the seedlings, there was no significant difference in two of them (the collar diameter and the dry matter of the root) and the indication of significant difference within the others (height, number of leaves, dry matter of aerial parts, leaf area and nickel concentration in the soil after removing the seedlings). However, this difference does not disagree with the goals of phytoremediation, for the progress of all the seedlings was continuous. Moreover, results reveal a great potential of G. ulmifolia tolerance to high levels of nickel concentration, making itself promising in the phytoremediation of contaminated soils by nickel. / Os despejos irregulares de metais pesados no meio ambiente provêm, em sua grande maioria, da atividade mineradora. Dentre os metais explorados na mineração, está o níquel, um elemento químico que apresenta grande potencial de toxicidade à fauna, flora e seres humanos. Com o intuito de se evitar que o níquel cause danos à saúde dos seres vivos, há como alternativa, a descontaminação do solo por meio da fitorremediação, tecnologia, que utiliza espécies de plantas resistentes a metais pesados e capazes de extraí-los, degradá-los, contê-los e ou imobilizá-los no solo. Assim sendo, o objetivo da presente pesquisa foi avaliar a germinação, crescimento e desenvolvimento inicial de sementes e plantas jovens da espécie Guazuma ulmifolia Lam. submetidas a diferentes concentrações de níquel, visando sua utilização em programas de recuperação de áreas contaminadas por este metal. Desta forma, os experimentos foram divididos em duas etapas. Na primeira, as sementes de G. ulmifolia foram distribuídas em seis tratamentos com Ni (NO3)2 [C (0 mg.L-1), T1 (20 mg.L-1), T2 (40 mg.L-1), T3 (60 mg.L-1), T4 (80 mg.L-1) e T5 (100 mg.L-1)], com quatro repetições por tratamento e 20 sementes por repetição. Em uma segunda etapa, foram utilizadas mudas de G. ulmifolia distribuídas em cinco tratamentos com Ni (NO3)2 [C (0 mg.L-1), T1 (100 mg.L-1), T2 (200 mg.L-1), T3 (400 mg.L-1) e T4 (600 mg.L-1)], cada tratamento foi estabelecido com sete repetições e cada repetição foi considerada como sendo uma muda em um recipiente plástico contendo 1000 cm³ de substrato. Ao final dos experimentos, os dados obtidos foram analisados através do teste ANOVA seguido pelo teste de comparações múltiplas de Tukey. Os resultados da estatística, mostraram-se não significativos para a germinação e significativos para o comprimento radicular e mortalidade após a germinação de G. ulmifolia, o que dificulta o emprego do plantio direto de suas sementes em programas de fitorremediação. Com relação aos parâmetros estabelecidos para as mudas, detectou-se inexistência de diferença significativa em dois deles (diâmetro do coleto e matéria seca da raiz) e presença de diferença significativa nos demais (altura, número de folhas, matéria seca da parte aérea, área foliar e concentração de níquel no solo depois da retirada das mudas). Essa diferença, contudo, não permanece em discordância com o propósito da fitorremediação, pois o progresso de todas as mudas foi contínuo. Por conseguinte, os resultados revelam para um grande potencial de tolerância de G. ulmifolia a elevadas concentrações do metal pesado níquel, tornando-se promissora na fitorremediação de solos contaminados pelo mesmo.
173

AVALIAÇÃO DO CRESCIMENTO INICIAL DAS ESPÉCIES HANDROANTHUS AVELLANEDAE (Lorentz ex Griseb.) Mattos E HANDROANTHUS SERRATIFOLIUS (Vahl.) S. Grose (BIGNONIACEAE-LAMIALES) EM DIFERENTES DOSAGENS DE NÍQUEL.

Xavier, Elitânia Gomes 01 August 2014 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-08-18T12:28:55Z No. of bitstreams: 1 Elitania Gomes Xavier.pdf: 1211897 bytes, checksum: cd94d5d9bfa170bb6ed73dc50e138f2b (MD5) / Made available in DSpace on 2016-08-18T12:28:55Z (GMT). No. of bitstreams: 1 Elitania Gomes Xavier.pdf: 1211897 bytes, checksum: cd94d5d9bfa170bb6ed73dc50e138f2b (MD5) Previous issue date: 2014-08-01 / This research seeks for statistic evidences which show that Handroanthus serratifolius and Handroanthus avellanedae are able to survive, endure and develop in different nickel dosages in the soil. These species have ornamental, landscaping, timber and medicinal potential, they can provide income while decontaminate the soil. The experiment (Figure 3a) was carried out with five by applying the following dosages of Ni: 0.0 mg.L-1, 20.0 mg L-1, 40.0 mg L-1, 60.0 mg L-1 and 80mg.L-1 and 100.0 mg l-1, each treatment had seven repetitons. The different solutions containing nickel were obtained by dilution of a stock standard solution (100.0 mg l-1) using (NiNO3) 2. The growth analysis is a method that describes the morphophisiological conditions of the plant at certain times, to quantify its development (Magalhães, 1979). It allows to know the functional and structural differences among the plants and to estimate the biomass formation, to identify responses to treatments (BENINCASA, 2003). For data analysis, statistical tests were performed using ANOVA. Different concentrations of the heavy metal nickel did not affect significantly the growth and development of the Handroanthus avellanedae and Handroanthus serratifolius species regarding the height, diameter, leaf area, dry weight of the air part, dry weight of roots and anatomical cuts parameters. It was concluded that the surveyed plants can tolerate the presence of the heavy metal Ni during the initial growth period. The anatomical structure also was not altered by the application of nickel, remaining without cell and tissue damages. These species have potential for use in contaminated areas by nickel, once the concentration supported is higher than Brazilian law calls for this heavy metal. / Essa pesquisa lançou-se a busca evidencias estatísticas que demonstrem que as Handroanthus avellanedae e Handroanthus serratifolius são capazes de sobreviver, tolerar e se desenvolver em diferentes dosagens de níquel no solo. Estas espécies possuem potencial ornamental, paisagístico, madeireiro e medicinal podem gerar renda e ao mesmo tempo descontaminar o solo. O experimento (Figura 3a) foi realizado com cinco tratamentos aplicando as seguintes dosagens de Ni: 0,0mg.L-1, 20,0mg.L-1, 40,0mg.L-1, 60,0mg.L-1, e 80mg.L-1 e 100,0mg.L-1, cada tratamento teve sete repetições. As diferentes soluções contendo níquel foram obtidas pela diluição de uma solução estoque padronizada (100,0mg.L-1) utilizando (NiNO3)2. A análise de crescimento é um método que descreve as condições morfofisiológicas da planta em períodos determinados, para se quantificar o seu desenvolvimento (MAGALHÃES, 1979). Permite conhecer as diferenças funcionais e estruturais entre plantas e estimar o acúmulo de fitomassa, de forma a identificar respostas aos tratamentos (BENINCASA, 2003). Para analise dos dados foram realizados testes estatísticos, utilizando o teste de ANOVA. As diferentes concentrações do metal pesado níquel não afetaram de forma significativa o crescimento e desenvolvimento das espécies Handroanthus avellanedae e Handroanthus serratifolius em relação aos parâmetros da altura, diâmetro, área foliar, peso seco da parte aérea, peso seco das raízes e nos cortes anatômicos. Concluiu-se que as plantas pesquisadas podem ser tolerantes a presença do metal pesado Ni durante o período de crescimento inicial. A estrutura anatômica igualmente não foi alterada pela aplicação de níquel, permanecendo sem danos celulares e tissulares. As espécies avaliadas possuem potencial para uso em áreas contaminadas por níquel, vez que a concentração suportada é maior do que preconiza a legislação brasileira para este metal pesado.
174

Uso da Pistia stratiotes como fitorremediadora de recursos hídricos contaminados por clomazone

Escoto, Dandara Fidélis 20 March 2017 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T13:54:36Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T13:54:50Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) / Made available in DSpace on 2017-06-05T13:54:50Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) Previous issue date: 2017-03-20 / With the growth of world population and the advent of industrialization, the demand for abundant and profitable food production worldwide is increasing. There is then a need for strategies that minimize loss and changes in food products, especially those that are grown for long periods of time like grains and vegetables. In this bias arise the pesticides, marketed since the nineteenth century, increasingly specialized and chemically modified to achieve greater efficiency in pest elimination and a shorter period of time. When pesticides are used correctly, they minimize grain losses by over 40%, but when used improperly or above the recommended dosage, they can lead to environmental and public health impacts. In this context, Clomazone (2 - (2-chlorobenzyl) -4,4-dimethyl-1,2-oxazolidin-3-one), active principle of the commercial herbicide Gamit®, of the Isoxazolidinone family and belonging to toxicological class III is Of broad spectrum used for the control of annual grasses and broadleaf weeds in cotton, peas, squash, soybeans, sweet potatoes, tobacco, wheat and rice. However, this herbicide has a series of physico-chemical characteristics and distinct behavior depending on the environment where it is inserted which can cause the increase of its permanence in the environment and contamination of organisms that are not its origin targets. An alternative to reduce the environmental impact caused by herbicides is phytoremediation. Phytoremediation consists of a technique of removal and / or pollutants from environments using plants as environmental remediation agents. This study aimed to evaluate the ability of the Pistia Stratiotes plant species in phytoremediation of the herbicide clomazone in its commercial form of water resources. The assay lasted 24 days and counted on two herbicidal concentrations that were determined from the one hundred fold multiplication of the dose recommended for use in crops, setting up an acute exposure to the herbicide. The clomazone degradation kinetics analyzes were performed by analytical methods by high performance liquid chromatography coupled to a detector with CLAE-DAD diode array. After 24 days of experiment, it was possible to identify that the plant species was able to reduce the presence of the herbicide clomazone in water by 90% and also that despite the water exposure to P. stratiotes does not undergo morphological changes due to sensitivity to the compound. Thus, the results indicate that Pistia Straiotes is capable of phytoremediation of the herbicide clomazone of water resources. / Com o crescimento da população mundial e o advento da industrialização cada vez mais aumenta a demanda pela produção abundante e rentável de alimentos pelo mundo todo. Existe então a necessidade de estratégias que minimizem a perda e as alterações nos produtos alimentares, sobretudo os que são cultivados por longos períodos de tempo como grãos e hortaliças. Neste viés surgem os pesticidas, comercializados desde o século XIX, cada vez mais especializados e modificados quimicamente para atingir uma maior eficiência na eliminação de pragas e um menor período de tempo. Quando os pesticidas são usados corretamente, eles minimizam acima de 40% as perdas de grãos, mas quando usados de maneira incorreta ou acima da dosagem recomendada, podem conduzir a impactos no ambiente e na saúde pública. Neste contexto, o Clomazone (2 - (2-clorobenzil) -4,4-dimetil-1,2-oxazolidin-3-ona), princípio ativo do herbicida comercial Gamit®, da família das Isoxazolidinona e pertencente a classe toxicológica III é de amplo espectro usado para o controle de gramíneas anuais e plantas daninhas de folha larga em algodão, ervilhas, abóbora, soja, batata-doce, tabaco, trigo e arroz. Porém, este herbicida possui uma série de características físico-químicas e comportamento distinto dependentemente do ambiente onde for inserido o que pode causar o aumento de sua permanência no ambiente e contaminação de organismos que não são os seus alvos de origem. Uma alternativa para reduzir o impacto ambiental causado pelos herbicidas é a fitorremediação. A fitorremediação consiste em uma técnica de remoção e/ou de poluentes dos ambientes utilizando plantas como agentes de remediação ambiental. Este estudo teve como objetivo avaliar a capacidade a espécie vegetal Pistia stratiotes em fitorremediar o herbicida clomazone em sua forma comercial de recursos hídricos. O ensaio teve a duração de 24 dias e contou com duas concentrações o herbicida que foram determinadas a partir da multiplicação em cem vezes da dose recomendada para uso em lavouras, configurando uma exposição aguda ao herbicida. As análises da cinética de degradação do clomazone foram realizadas através de métodos analíticos por cromatográfica líquida de alta eficiência acoplada a detector com arranjo de diodos CLAE-DAD. Após os 24 dias de experimento foi possível identificar que a espécie vegetal foi capaz de reduzir em 90% a presença do herbicida clomazone na água e também que apesar da exposição agua a P. Stratiotes não sofre alterações morfológicas em decorrência de sensibilidade ao composto. Dessa maneira, os resultados indicam que a Pistia Straiotes é capaz de fitorremediar o herbicida clomazone de recursos hídricos.
175

Enhancement of metal ion removal capacity of water hyacinth.

January 2001 (has links)
by So Lai Man, Rachel. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 83-103). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.iv / List of Figures --- p.viii / List of Tables --- p.ix / Chapter 1. --- Literature Review --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Overview of metal ions pollution --- p.2 / Chapter 1.3 --- Treatment of metal ions in wastewater --- p.4 / Chapter 1.3.1 --- Conventional methods --- p.4 / Chapter 1.3.2 --- Microbial methods --- p.5 / Chapter 1.4 --- Phytoremediation --- p.6 / Chapter 1.4.1 --- Rhizofiltration --- p.10 / Chapter 1.4.2 --- Mechanisms of metal ion removal by plant root --- p.12 / Chapter 1.5 --- Using water hyacinth for wastewater treatment --- p.15 / Chapter 1.5.1 --- Biology of water hyacinth --- p.15 / Chapter 1.5.2 --- Water hyacinth based systems for wastewater treatment --- p.21 / Chapter 1.6 --- Biology of rhizosphere --- p.23 / Chapter 2. --- Objectives --- p.26 / Chapter 3 --- Materials and Methods --- p.28 / Chapter 3.1 --- Metal ion stock solution --- p.28 / Chapter 3.2 --- Plant material and growth conditions --- p.28 / Chapter 3.2.1 --- Preparation of Hoagland solution --- p.28 / Chapter 3.3 --- Metal ion resistance of water hyacinth --- p.31 / Chapter 3.4 --- Effect of metal ion concentration on the bacteria population --- p.31 / Chapter 3.4.1 --- Minimal medium (MM) --- p.31 / Chapter 3.5 --- Isolation of rhizospheric metal ion-resistant bacteria --- p.34 / Chapter 3.6 --- Metal ion removal capacity of isolated bacteria --- p.34 / Chapter 3.7 --- Colonization efficiency of a metal ion-adsorbing bacterium onto the root --- p.35 / Chapter 3.7.1 --- Suppression of the bacterial population in the rhizosphere by an antibiotic --- p.35 / Chapter 3.7.2 --- Colonization efficiency --- p.36 / Chapter 3.8 --- Effect of colonizing the metal ion-adsorbing bacteria on the metal ion removal capacity of roots --- p.37 / Chapter 4. --- Results --- p.38 / Chapter 4.1 --- Selection of optimum metal ion concentration for water hyacinth and rhizo spheric bacteria --- p.38 / Chapter 4.1.1 --- Metal ion resistance of water hyacinth --- p.38 / Chapter 4.1.2 --- Effect of metal ion concentration on population of rhizospheric bacteria --- p.43 / Chapter 4.1.3 --- Selection for optimum metal ion concentration for water hyacinth and rhizospheric bacteria --- p.43 / Chapter 4.2 --- Screening for bacterial strain with high metal ion resistance and removal capacity --- p.46 / Chapter 4.2.1 --- Enrichment of the metal ion-resistant bacteria in the rhizosphere --- p.46 / Chapter 4.2.2 --- Isolation of the natural bacterial population in rhizosphere --- p.50 / Chapter 4.2.3 --- Determination of the metal ion removal capacity of rhizospheric metal ion-resistant bacterial strains --- p.52 / Chapter 4.2.4 --- "Comparison of Cu2+, Ni2+ and Zn2+ removal capacities of Cu2+-resistant bacterial strains" --- p.53 / Chapter 4.3 --- Effect of inoculating Cu2+-resistant bacterial strain to the rhizosphere on the metal ion removal capacity of the root --- p.59 / Chapter 4.3.1 --- Bactericidal efficiency of oxytetracycline --- p.59 / Chapter 4.3.2 --- Effect of inoculating Cu2+-adsorbing bacterial cells into the rhizosphere --- p.62 / Chapter 4.3.3 --- Effect of bacterial cell density of inoculum on colonizing efficiency --- p.63 / Chapter 4.3.4 --- Colonizing efficiency and metal ion removal capacity of root by direct inoculation of metal ion-adsorbing bacterial cells into metal ion solution or pre-inoculation in Hoagland solution --- p.64 / Chapter 4.3.5 --- Effect of inoculating Strain FC-2-2 into the rhizosphere on the removal capacity of roots --- p.64 / Chapter 5. --- Discussion --- p.69 / Chapter 5.1 --- Selection of optimum metal ion concentration for water hyacinth and rhizospheric bacteria --- p.69 / Chapter 5.1.1 --- Metal resistance of water hyacinth --- p.69 / Chapter 5.1.2 --- Effect of metal ion concentration on population of rhizospheric bacteria population --- p.70 / Chapter 5.1.3 --- Selection for optimum concentration --- p.70 / Chapter 5.2 --- Screening for high metal ion-resistant and -removal bacterial strains --- p.71 / Chapter 5.2.1 --- Enrichment of the metal ion-resistant bacteria in the rhizosphere --- p.71 / Chapter 5.2.2 --- Select metal ion-resistant bacterial strain from the natural population in the rhizosphere --- p.72 / Chapter 5.2.3 --- Determination of the metal ion removal capacity of respective metal ion-resistant bacterial strain --- p.72 / Chapter 5.3 --- Effect of inoculating Cu2+-resistant bacterial strain in the rhizosphere on the metal ion removal capacity of the root --- p.74 / Chapter 5.3.1 --- Bactericidal efficiency of oxytetracycline --- p.74 / Chapter 5.3.2 --- Effect of inoculating Cu2十-adsorbing bacterial cells into the rhizosphere --- p.75 / Chapter 5.3.3 --- Effect inoculum cell density on the colonizing efficiency --- p.76 / Chapter 5.3.4 --- Comparison of colonizing efficiency and metal ion removal capacity of root by direct inoculation metal ion-adsorbing bacterial cells into metal solution or pre-inoculationin Hoagland solution --- p.77 / Chapter 5.3.5 --- Effect of inoculating strain FC-2-2 into the rhizosphere on the removal capacity of roots --- p.78 / Chapter 5.4 --- Limitation and future development --- p.79 / Chapter 6. --- Conclusion --- p.81 / Chapter 7. --- References --- p.83
176

Avaliação das alterações morfológicas, anatômicas e fitoquímicas em folhas de Mentha x Villosa (LAMIACEAE) cultivada em solo contaminado com petróleo e potencial de uso na fitorremediação. / Evaluation of morphological, anatomical and phytochemical in leaves of Mentha x Villosa (LAMIACEAE) grown in soil contaminated with oil and potencial use in phytoremediation.

Chaiana Macena Wolff 30 March 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A exploração, processamento, transporte, armazenamento e utilização do petróleo e seus derivados têm resultado em acidentes e vazamentos de proporções variadas e existe uma demanda crescente por soluções técnica, ambiental e economicamente viáveis. É nesse contexto que a fitorremediação ganha evidência e se mostra adequada por aliar um custo-benefício atraente. A fitorremediação utiliza espécies vegetais para extrair, conter, imobilizar ou degradar contaminantes do solo e da água. Além disso, a possibilidade de crescer espécies de valor comercial em solos contaminados que, de outra forma, não teriam qualquer uso, torna-se uma alternativa atraente. O presente trabalho tem por objetivo avaliar a capacidade de fitorremediação de Mentha x Villosa e as alterações fisiológicas e morfológicas em decorrência da contaminação dos solos por petróleo em quatro concentrações (0%, 2%, 4% e 6% p/p) com seis repetições. As variáveis analisadas foram: taxa de sobrevivência, biomassa total seca e fresca, dimensão foliar, densidade de estômatos e densidade de tricomas. Foram feitas análises de hidrcarbonetos totais de petróleo - HTPs presntes no solo no início do experimento e após 90 dias de cultivo. As plantas crescidas em solo contaminado tiveram uma taxa de sobrevivência de 100%. Houve uma tendência ao xeromorfismo nas plantas mantidas em solo contaminado. De acordo com a análise one-way ANOVA (Tukey, I.C. 95%), houve redução significativa da biomassa fresca em plantas crescidas na presença de petróleo em qualquer concentração quando compradas ao controle e, também, redução significativa entre as concentrações 2% versus 4% e 2% versus 6%. Entretanto plantas crescidas em 4% e em 6% não diferiam entre si. Como não houve diferença significativa da biomassa seca para nenhum par, conclui-se que as diferenças observadas em biomassa fresca decorrem da menor absorção e/ou retenção de água por plantas crescidas na presença de petróleo. A presença do petróleo em qualquer concentração resultou em aumento significativo da densidade dos estômatos quando comparada ao controle (0%), particularmente aos 90 dias. Entretanto, não houve diferença significativa entre as plantas crescidas em petróleo nas diferentes concentrações. Aos 30 dias observou-se aumento significativo da densidade dos tricomas apenas em plantas na concentração 6%, comparadas ao controle (0%) e às demais concentrações (2% e 4%). Aos 60 dias, um aumento significativo da densidade de tricomas foi observado em plantas crescidas em todas as concentrações de petróleo (2%, 4% e 6%), quando comparadas ao controle e aos 90 dias, tais diferenças foram mantidas. Mentha x Villosa mostrou ser uma planta com potencial para crescer em solo contaminado com petróleo, sendo que aos 90 dias foi observada uma remoção de 99,90% de HTPs no solo contaminado a 2% (p/p) e de 99,98% de remoção de HTPs no solo contaminado a 4% (p/p).
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Avalia??o de estrat?gias para remedia??o de solo contaminado por chumbo e b?rio provenientes de res?duos de perfura??o de po?o de prospec??o de petr?leo / Evaluation of strategies for remediation of soil contaminated by lead and barium, from well drilling oil prospecting waste

ANDRADE, Andr? Fern?o Martins de 31 August 2010 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2016-10-04T21:35:58Z No. of bitstreams: 1 2010 - Andr? Fern?o Martins de Andrade.pdf: 4307696 bytes, checksum: d679370ce9902b97ed91c98436c9103a (MD5) / Made available in DSpace on 2016-10-04T21:35:58Z (GMT). No. of bitstreams: 1 2010 - Andr? Fern?o Martins de Andrade.pdf: 4307696 bytes, checksum: d679370ce9902b97ed91c98436c9103a (MD5) Previous issue date: 2010-08-31 / UNIFOA / This study begun with a field survey in a one hectare area of petroleum drill waste (rocks and mud came from perforation) in Santa Maria do Oeste, in Paran? state, Brazil. It was verified different levels of metal contamination in the area, according to the surface position and with depth, with barium and lead over the investigation standard according to legislation. The highest level contaminated material was collected and used in a laboratory and greenhouse experiment at the campus of the Universidade Federal Rural do Rio de Janeiro, initiated on December, 2007, and completed on June, 2010. The objective was to evaluate the efficiency of remediation by washing contaminated soil (in situ and ex-situ) as well as phytoremediation. The waste washing ex-situ was simulated such as the contaminant would be removed from soil using a rotating device, with soil mixed with an ethylenediaminetetraacetic acid (EDTA) solution in the proportion of 1:10. Removal of lead and calcium increased proportionally to concentration of extractor (from 100 to 1500 mmol L-1). Removal of barium increased considerably above 600 mmol L-1. Iron and manganese showed little influence by different concentration of extractor. The soil washing in-situ was simulated by addition of two solutions of EDTA, with concentration of 150 and 300 mmol L-1, and the control (water). The material was incubated in plastic columns, for three weeks, after that volumes of 100 mL of deionized water were added weekly for three weeks, and after that samples were taken daily up to a total of ten. The leached was collected and the barium and lead content were analyzed, also other metals that could interfere with the extraction. The fractions (exchangeable, iron bound, organic matter bound, and residual) that metals were associates in the waste, before and after washing, were also determined. It was found, in the higher EDTA concentration, a small extraction of barium, while lead had about 20% of the total in soil extracted. The phytoremediation was carry on with two species, Brachiaria decumbens cv. Basilisk, an herbaceous plant, and Cordia africana, an arboreal. The plants growing up in vases with 4 kg of substratum were irrigated with deionized water and Hoagland nutrient solution (25% of ionic power). Two treatments were used in the phytoextraction induced with EDTA, in the concentration of 6 mmol L-1 (with one single application, and 3 dosages of 2 mmol L-1), plus the control. After 150 days for Brachiaria and 270 days for Cordia, the plants were collected, and analyzed (root and shoots) for heavy metal content. EDTA was effective to induce metal absorption, except for barium and calcium, where lead concentrated in the roots and barium in leaves (with highest concentration for EDTA applied in one dose). For Cordia, barium distributed equally in the plant sections, and lead concentrated in the roots. / Este trabalho iniciou-se com levantamento de campo na ?rea de despejo do res?duo de perfura??o de po?o de prospec??o de petr?leo (cascalhos e fluidos da broca) em Santa Maria do Oeste, Estado do Paran?, que possui ?rea aproximada de um hectare. Constatou-se que a ?rea apresentava diferentes n?veis de contamina??o de metais, estando, de acordo com sua posi??o no plano e em profundidade, com n?veis de b?rio e o chumbo na faixa de investiga??o, conforme norma legal. O material com maior n?vel de contamina??o foi coletado e utilizado em experimento de laborat?rio e casa de vegeta??o no campus da Universidade Federal Rural do Rio de Janeiro, a partir do m?s de dezembro de 2007 e finalizado em junho de 2010. Objetivou-se avaliar a efici?ncia da remedia??o atrav?s da lavagem do solo contaminado (in situ e ex-situ) bem como da sua fitorremedia??o. A lavagem do res?duo ex-situ foi simulada como aquela em que o contaminante seria removido do solo em um reator rotativo, onde o solo seria misturado em batelada a solu??o de EDTA na propor??o 1:10. A remo??o de chumbo e c?lcio aumentou com o aumento da concentra??o do extrator (de 100 a 1500 mmol L-1). A remo??o do b?rio aumentou consideravelmente acima de 600 mmol L-1; ferro e mangan?s foram pouco influenciados pelas diferentes concentra??es. A lavagem do solo in situ foi feita com adi??o de duas solu??es de ?cido etilenodiamino tetra-ac?tico diss?dico (Na2EDTA), de concentra??es 150 e 300 mol L-1, al?m da testemunha (?gua), em colunas est?ticas que, ap?s um per?odo de tr?s semanas de incuba??o, receberam 100 mL de ?gua deionizada a cada semana por tr?s semanas e, depois, uma coleta por dia at? perfazer 10 coletas. Os lixiviados foram coletados e analisados os teores dos contaminantes b?rio e chumbo, al?m de outros metais interferentes com a extra??o. Determinou-se, ainda, as diversas fra??es (troc?vel, ligada a ?xidos, ligada ? mat?ria org?nica e residual) em que esses metais se encontravam no res?duo antes e ap?s a lavagem. Foi verificada, na maior concentra??o de EDTA, extra??o insignificante de b?rio, enquanto o chumbo teve extra?do cerca de 20% do seu total no solo. A fitorremedia??o deu-se por meio do uso de duas esp?cies, uma herb?cea (Brachiaria decumbens cv. Basilisk) e outra lenhosa (Cordia africana). As plantas se desenvolveram em vasos com 4 kg de substrato, recebendo fertirriga??o (solu??o de Hoagland a 25% de for?a i?nica). Foram usados dois tratamentos na fitoextra??o induzida com EDTA, na concentra??o de 6 mmol L-1 em duas formas de aplica??o (3 aplica??es de 2 mmol.L-1 e uma de 6 mmol L-1) e a testemunha. Ap?s per?odo de desenvolvimento de 150 dias para a braqui?ria e de 270 dias para a c?rdia, as plantas foram coletadas tendo suas ra?zes e a parte a?rea analisada quanto ao conte?do de metais. Na braqui?ria, o EDTA foi efetivo na indu??o da absor??o dos metais com exce??o do b?rio e do c?lcio, tendo o chumbo se concentrado nas ra?zes e o b?rio nas folhas (com maior concentra??o no tratamento de aplica??o ?nica de EDTA). Na c?rdia, o b?rio distribuiu-se igualmente entre as partes analisadas e o chumbo se concentrou nas ra?zes.
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Avaliação do destino final da biomassa de Landoltia punctata para compostagem por aeração natural com resíduos de podas de árvore /

Trolezi, Lígia Maria January 2019 (has links)
Orientador: Liliane Lazzari Albertin / Resumo: A degradação da qualidade da água é principalmente resultado de contaminantes de fontes difusas e da variabilidade espaço-temporal associada a essas fontes, além da falta de sistemas de coleta e tratamento de esgoto. Esse problema, de poluição pontual, pode ser amenizado em estações de tratamento de esgoto, pela implementação de tecnologias novas e eficientes, ou modificação do convencional em direção ao conceito de sustentabilidade. Neste contexto, o uso de macrófitas é uma alternativa de tecnologia de complexidade baixa, eficiente e econômica. As macrófitas têm uma alta taxa de reprodução e alta produção de biomassa, resultando em uma grande capacidade de remover compostos contaminantes dos esgotos. Além disso, as plantas aquáticas cultivadas em esgoto isento de metais pesados também podem ser utilizadas como fertilizantes na agricultura. Desta forma, o objetivo desta pesquisa foi avaliar o uso potencial da biomassa da macrófita, Landoltia punctata, como material nitrogenado associado a resíduos de podas de árvores, e outros materiais carbonáceos, em compostagem para produção de composto orgânico, bem como avaliar a composição físico-química do composto. O uso da Landoltia punctata em tratamento de polimento de efluentes apresenta a melhora da qualidade da água dos corpos de crescimento d'água e contribui para minimizar o problema da eutrofização no meio aquático. Porém sua alta taxa de crescimento e produção dificulta sua aplicação em larga escala, levantando questões para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The degradation of water quality is mainly a result of contaminants from diffuse sources and the spatiotemporal variability associated to these sources, as well as the lack of sewage collection and treatment systems. This problem of punctual pollution can be mitigated in sewage treatment plants, through the implementation of new and efficient technologies, or modification of the conventional towards the concept of sustainability. In this context, the use of macrophytes is a technology alternative of low complexity, efficient and economical. Macrophytes have a high reproductive rate and high biomass production, resulting in a large capacity to remove contaminating compounds from sewage. In addition, aquatic plants grown in sewage free of heavy metals can also be used as fertilizers in agriculture. Thus, the objective of this research was to evaluate the potential use of macrophyte biomass, Landoltia punctata, as nitrogenous material associated with tree pruning residues and other carbonaceous materials, in composting for organic compost production, as well as to evaluate the physical composition. -chemical of the compound. The use of Landoltia punctata in effluent polishing treatment improves the water quality of water bodies and contributes to minimize the problem of eutrophication in the aquatic environment. However, its high rate of growth and production hampers its application on a large scale, raising questions for its safe disposal, since its biomass is characterized as ... (Complete abstract click electronic access below) / Mestre
179

Water Quality Performance And Greenhouse Gas Flux Dynamics From Compost-Amended Bioretention Systems & Potential Trade-Offs Between Phytoremediation And Water Quality Stemming From Compost Amendments

Shrestha, Paliza 01 January 2018 (has links)
Stormwater runoff from existing impervious surfaces needs to be managed to protect downstream waterbodies from hydrologic and water quality impacts associated with development. As urban expansion continues at a rapid pace, increasing impervious cover, and climate change yields more frequent extreme precipitation events, increasing the need for improved stormwater management. Although green infrastructure such as bioretention has been implemented in urban areas for stormwater quality improvements and volume reductions, these systems are seldom monitored to validate their performance. Herein, we evaluate flow attenuation, stormwater quality performance, and nutrient cycling from eight roadside bioretention cells in their third and fourth years of implementation in Burlington, Vermont. Bioretention cells received varying treatments: (1) vegetation with high-diversity (7 species) and low-diversity plant mixes (2 species); (2) proprietary SorbtiveMediaTM (SM) containing iron and aluminum oxide granules to enhance sorption capacity for phosphorus; and (3) enhanced rainfall and runoff (RR) to certain cells (including one with SM treatment) at three levels (15%, 20%, 60% more than their control counterparts), mimicking anticipated precipitation increases from climate change. Bioretention water quality parameters monitored include total suspended solids (TSS), nitrate/nitrite-nitrogen (NOx), ortho-phosphorus (Ortho-P), total nitrogen (TN) and total phosphorus (TP), which were compared among bioretention cells’ inflows and outflows across 121 storms. Simultaneous measurements of flow rates and volumes allowed for evaluation of the cells’ hydraulic performances and estimation of pollutant load and event mean concentration (EMC) removal. We also monitored soil CO2 and N2O fluxes, as they represent a potential nutrient loss pathway from the bioretention cells. We determined C and N stocks in the soil media and vegetation, which are critical design elements of any bioretention, to determine the overall C and N balances in these systems. Significant average reductions in effluent stormwater volumes and peak flows were reported, with 31% of the storms events completely captured. Influent TSS loads and EMCs were well retained by all cells irrespective of treatments, storm characteristics, or seasonality. Nutrient removal was treatment-dependent, where the SM treatments consistently removed P loads and EMCs, and sometimes N as well. The vegetation and RR treatments mostly exported nutrients to the effluent. We attribute observed nutrient exports to the presence of excess compost in the soil filter media. Rainfall depth and peak inflow rate undermined bioretention performance, likely by increasing pollutant mobilization through the filter media. While the bioretention cells were a source of CO2, they varied between being a sink and source of N2O. CO2 fluxes were orders of magnitude higher than N2O fluxes. However, soil C and N, and plant C and N in biomass was seen to largely offset respiratory CO2-C and biochemical N2O-N losses from bioretention soil. The use of compost in bioretention soil media should be reduced or eliminated. If necessary, compost with low P content and high C: N ratio should be considered to minimize nutrients losses via leaching or gas fluxes. In order to understand trade-offs stemming from compost amendments, we conducted a laboratory pot study utilizing switchgrass and various organic soil amendments (e.g., different compost types and coir fiber) to a sandy loam soil contaminated with heavy metals and studied potential nutrient leaching and pollutant uptake. Addition of organic amendments significantly reduced metal bioavailability, and improved switchgrass growth and metal uptake potential. While no differences in soil or plant metal uptake were observed among the amendments, significant differences in nutrient leaching were observed.
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Smooth Cord Grass (Spartina Alterniflora) Response to Simulated Oil Spills in Sediment-Water Microcosms

Beenk, Elliott E. 01 July 2013 (has links)
Simulated oil spills were created in S. alterniflora sediment-water microcosms to determine the effects of applied crude oil on S.alterniflora during two 90-day studies. In the first experiment, oil dosage was varied at 0-250 mg crude oil/g wet soil to determine the lethal dosage level. In the second experiment, oil type, dosage, and soil type were varied to determine the effects of oil under multiple scales of resolution. A light, medium, and heavy crude oil at dosages ranging from 0-150 mg crude oil/g wet soil were used in addition to an oiled and non-oiled soil. Following the completion of the 90-day experiment, several key findings were observed: (1) The lethal dosage limit was reached at 250 mg crude oil/g wet soil during the first experiment but not the second, by design; (2) At initial dosages of 10 and 50 mg crude oil/g wet soil, the oiled soil (acclimated for 4 months) was more influential in decreasing cumulative biomass growth rates compared to oil applied at the oil-water interface; (3) At the heaviest dosages applied as a simulated oil slick, concentrations of 150 mg crude oil/g wet soil, evapotranspiration rates were negatively affected by the oil (significant at p=0.05 in a one-tailed t-test); (4) Light, heavy, and then medium crude oil showed the lowest biomass growths, in that order, indicating that light crude oil was the most toxic in these microcosm experiments with S. alterniflora; (5) The 10 mg oil/g wet soil out-performed the 0 mg oil/g wet soil in transpiration and biomass growth.

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