Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (M.S.)--Northern Michigan University, 2006. / Includes bibliographical references (leaves 56-67).

Techn. Hochsch., Diss., 2004--Aachen.

Thesis (M.A.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 57-62). Also available via Humboldt Digital Scholar.

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 115 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 78-80).

Brominated flame retardants have been widely used in industry. There is a rapidly growing public concern about their ubiquity in the environment. This project investigated the possible removal treatments of polybrominated diphenyl ethers (PBDEs) using two treatment methods: (I) photocatalysis by TiO2 and (II) phytoremediation by Oryza sativa and Phragmites australis, and a combined system involving these two technologies. Advanced oxidation process (AOP) is a promising technology for removing emerging chemicals. In this case, nano-scaled titanium (IV) oxide was applied to evaluate its capability in the degradation of BDE-209 under visible light. The residual PBDE congeners after reaction were analyzed by gas chromatography-mass spectrometry (GC-MS). The half-life for removing BDE-209 by TiO2 was 3.05 days under visible light. Tetra- and penta-BDEs were the major degraded products of BDE-209. Optimum conditions for photocatalytical degradation of BDE-209 was found to be pH 12 (93% ± 1%), at least 5 mg/L (93 ± 1.70%) of humic acid and in the form of anatase/rutile TiO2 (82% ± 3%). Incomplete removal of PBDEs by water treatment plants and point-source contamination may lead to their discharge into water bodies and ultimately into soils. Consequently, the second part of the project was phytoremediation of PBDEs. Uptake of BDE-209 by rice cultivars, namely Fengmeizhan, Hefengzhan and Guangyinzhan, and common reed were examined by 60-day cultivation in sterilized BDE-209 spiked soil. Hefengzhan possessed the greatest ability in the removal and accumulation of BDE-209 among the three cultivars, especially when associated with Glomus intraradices, at pH 7. A series of plant-contamination sorption analyses were also employed for pathway studies of PBDEs uptake by rice. A partition-limited model was applied for describing and estimating the uptake of BDE-209 by rice roots. The average quasi-equilibrium factors (apt) of BDE-47, -99 and -209 in root uptake were 1.44 × 10-3 , 0.966 × 10 -3 and 0.115 × 10-3 in sand (< 1), implying a non-equilibrium state of the movement of molecules and a dominant passive transport uptake. From the result of sorption analysis of dead and fresh roots, the apoplastic pathway likely dominated the transport of PBDEs into root cells. These results provide essential information on the uptake mechanism of PBDEs into plants. Based on the results from photocatalysis and phytoremediation, a combined photocatalysis (TiO2 and visible light) and constructed wetland system (Oryza sativa (Hefengzhan) and Phragmites australis (common reed) was set up for comparing PBDEs removal efficiencies. The removal percentages of BDE-209 in the combined system were found to be promoted when compared to the individual systems, which could be explained by enhanced biodegradability of PBDEs in photocatalysis. Therefore, the proposed advanced wastewater treatment technology (combined photocatalysis and constructed wetland systems) might help to degrade and eliminate BDE-209 in the wastewater, and thus reduce the risks of marine contamination by discharging these incompletely or partially treated wastewaters containing PBDEs.

Orientador: Paulo Sergio Tonello / Coorientador: Danielle Goveia / Banca: Luciana Camargo de Oliveira / Banca: Gustavo Ventorim / Resumo: A fitorremediação é um método que utiliza plantas para recuperação de solos contaminados. Esse método apresenta vantagens devido à sua natureza permanente, combinada a baixos custos de manutenção, proteção contra a erosão eólica e hídrica e maior estruturação dos solos. Espécies florestais como pinus podem ser apropriadas para a revegetação de áreas contaminadas e propiciar ainda retorno econômico. Este trabalho teve como objetivo avaliar a tolerância, o acúmulo e a distribuição de diferentes concentrações dos íons zinco e cobre em mudas de Pinus elliottii em condições de viveiro e considerar o potencial fitorremediador da espécie na região de Itapeva - SP. Para isso foi realizada a montagem de sistemas de fitorremediação em escala piloto. O solo foi contaminado com quantidades definidas de Zn e Cu equivalentes a 0, 1, 2 e 3 vezes o valor definido como de intervenção agrícola para o Estado de São Paulo. Adotou-se delineamento experimental inteiramente casualizado, com quatro repetições para cada tratamento. Determinou-se as concentrações dos metais no sistema radicular e foliar das mudas e no solo antes e após os seis meses de avaliação. Todos os parâmetros estudados foram submetidos a análises estatísticas paramétricas usuais e comparados por teste de confrontamento de médias Tukey a 5% de probabilidade. Os resultados mostraram redução dos teores de Cu e Zn no solo em relação aos valores iniciais em todos os tratamentos em que foi cultivado Pinus elliottii. Nas acículas houv... (Resumo completo, clicar acesso eletrônico abaixo) / Phytoremediation is a method that uses plants to recover contaminated soils. This method has advantages because of its permanent nature, combined with low maintenance costs, protection against wind and water erosion and greater soil structure. Forest species such as pinus may be appropriate for revegetation of contaminated areas and also provide economic return. The objective of this work was to evaluate the tolerance, accumulation and distribution of different concentrations of zinc and copper ions in Pinus elliottii seedlings under nursery conditions and to consider the phytoremediation potential of the species in the Itapeva - SP region. For this purpose, a pilot scale phytoremediation system was set up. The soil was contaminated with defined amounts of Zn and Cu equivalent to 0, 1, 2 and 3 times the value defined as agricultural intervention for the State of São Paulo. A completely randomized experimental design was used, with four replicates for each treatment. The concentrations of the metals in the root and leaf system of the seedlings and in the soil were determined before and after the six months of evaluation. All the parameters studied were submitted to usual parametric statistical analysis and compared by Tukey averages comparison test at 5% of probability. The results showed a reduction of the Cu and Zn levels in the soil in relation to the initial values in all the treatments in which Pinus elliottii was cultivated. In the needles there was an increase in the concentration of Cu in relation to the initial concentration in all experimental plots studied. It was found that the higher the dose of the metal in the soil, the higher the content recovered in the aerial part up to the dose corresponding to twice the agricultural intervention value. From this concentration we have ... (Complete abstract click electronic acess below) / Mestre

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Física, Química e Geológica, Instituto de Oceanografia, 2008. / Submitted by Cristiane Silva (cristiane_gomides@hotmail.com) on 2013-03-08T12:24:50Z No. of bitstreams: 1 2008_francine_viana.pdf: 2187831 bytes, checksum: 6e9edbfbd71025b57d9cfe607b5b3791 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-07-15T17:32:16Z (GMT) No. of bitstreams: 1 2008_francine_viana.pdf: 2187831 bytes, checksum: 6e9edbfbd71025b57d9cfe607b5b3791 (MD5) / Made available in DSpace on 2013-07-15T17:32:16Z (GMT). No. of bitstreams: 1 2008_francine_viana.pdf: 2187831 bytes, checksum: 6e9edbfbd71025b57d9cfe607b5b3791 (MD5) Previous issue date: 2008 / Foram determinadas as concentrações de hidrocarbonetos policíclicos aromáticos (HPAs) em plantas de marismas Spartina alterniflora, cultivadas em solo contaminado (landfarming) e em solo não contaminado. As concentrações de HPAs nas plantas foram quantificadas nas raízes, hastes, folhas e folhas mortas a fim de investigar a absorção e translocamento de HPAs através da planta. Para avaliar a remoção de HPAs pela S. alterniflora as concentrações foram medidas também no solo. As plantas apresentaram desenvolvimento semelhante até os 60 dias de experimento, quando as plantas cultivadas no solo não contaminado apresentaram um desenvolvimento significativamente maior. As variações nos teores de nutrientes no solo contaminando sugerem que neste tratamento ocorreu um desenvolvimento maior de microorganismos. Tanto no tratamento com solo contaminado como no cultivo em solo não contaminado, o fator de concentração nas raízes (RCF) mostrou que as raízes apresentaram as maiores concentrações de HPAs. Os fatores de concentração nas hastes, folhas e folhas mortas (SCF, FCF e FMFC, respectivamente) indicaram que os compostos de 2-4 anéis também foram assimilados pela S. alterniflora, como fenatreno, antraceno, pireno e criseno. No solo, as concentrações deste grupo de compostos reduziram tanto no tratamento com solo contaminado quanto no solo não contaminado. Os HPAs mais recalcitrantes (5-6 anéis) como benzo(b)fluoranteno e benzo(e)pireno ficaram limitados às raízes, não havendo redução nas concentrações do solo. A utilização de Spartina alterniflora após o tratamento biológico landfarming mostrou que a presença da planta é capaz de auxiliar na remoção de alguns HPAs do solo, seja pela remoção destes através da absorção direta pela planta, seja pela estimulação da microbiota associada às raízes, que realizam biodegradação. / Polycyclic aromatic hydrocarbons (PAHs) concentrations were measured in salt marshes plants Spartina alterniflora, grown in contaminated soil with landfarming waste and in uncontaminated control soil. Plant PAHs concentrations were quantified in roots, stems, leaves and fallen leaves in order to investigate HPAs uptake and translocation through the plant. To assess HPAs removal by S. alterniflora concentrations were measured also in the soil. The plants had similar development until the 60 days of trial, when the plants grown in uncontaminated soil had a significantly greater development. The variations in nutrients levels in contaminated soil suggest that this treatment was further development of microorganisms. Both in dealing with contaminated soil and in cultivation in uncontaminated soil, the roots concentration factor (RCF) showed that the roots had the largest concentrations of PAHs. The concentration factors on stems, leaves and fallen leaves (SCF, FCF and FMFC, respectively) indicated that the compounds of 2-4 rings have also been assimilated by the S. alterniflora, as phenantrene, anthracene, pyrene and chrysene. Soil concentrations of this group of compounds reduced in both treatments with contaminated soil, as in uncontaminated soil. More recalcitrant PAHs (5-6 rings) such benzo(b)fluoranthene and benzo(e)pyrene were limited to roots, with no reduction in soil concentrations. Spartina alterniflora used after a landfarming biological treatment showed that plant presence is capable of assisting some PAHs removal from soil, either by removing these through direct absorption by the plant, either by stimulating associated roots microorganisms by biodegradation.

There is a public concern over the potential accumulation of heavy metals in soils. Numerous studies have already demonstrated that areas in close proximity to vehicular traffic are marked noticeably by contamination of soil, air and water. Hence, such activities can affect humans and other living organisms. The aim of this study is to investigate the pollution of soils caused by vehicular traffic, on agricultural land in Azzawiyah, Liby with the view of assessing potential application of phytoremediation options for the remediation of contaminated soils and determine whether soil amendments would improve soil remediation. In an effort to improve the status of pollution of soils by vehicular traffic, a phytoremediation method of remediation of contaminated land has been used in this study, as it is relatively inexpensive and has the potential through the appropriate selection of plant species to be effective. This method is a soil clean up technology that uses the ability of metal accumulator plants to extract metal from contaminated soil with their roots and to concentrate these metals in above-ground plant parts. In this study, the investigation area was in Azzawiyah city where the soil samples and Doedonea viscose plant were collected from the road side. These soil samples were analysed using different experiments to determine physical and chemical properties, such as pH, OM and CEC. Heavy metals in soil and Doedonea viscose shoot and root were analysed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The findings of the study show that all soils samples collected along the highway road connecting Azzawiyah with the southern parts of Libya were found to be granular with a sandy texture. It is also found that the metal content in soil collected from the site, which is close to the roadside was relatively higher than that soil collected from the agricultural field in the same area. Furthermore, the level of Pb (840mg/kg-1) in roadside soils was higher than the natural levels of Pb in soils. In addition, Doedonea viscose plant was not a hyperaccumulor plant. Greenhouse experiments used three plants (E. camaldeulensis, Brassica Juncea and Medicago sativum) to uptake heavy metal, such as Cd, Zn and Pb from the soil samples. The greenhouse experiment results indicate that E. camaldeulensis was the best plant species for phytoremediation of Pb contaminated soils than the other two plants species (Brassica Juncea, Medicago sativum). The efficiency of the E. camaldeulensis was increased by adding amendments (e.g. compost, compost, EDTA, Hoagland solution and Alcaligenes eutrophus) to the plants pots in order to uptake the lead form soil samples. The results of the pots amendments experiments indicate that 15 mmol of EDTA and bacterial inoculums (Alcaligenes eutrophus) were the best amendments to extract lead from the soils. The study suggests that using the Alcaligenes eutrophus with the E. camaldeulensis are more suitable for phytoremediation in terms of accumulation and cost.

Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / The demand for better quality produce by consumers is on the increase, as higher heavy metal concentrations pose a problem in agriculture. They result in decreased yield and unsuitable food for human consumption. This brings about a negative economic effect as such products become unprofitable on the domestic or export markets thus affecting productivity of farms.Four heavy metals (Cd, Cu, Pb and Zn) have been shown to be a problem in the farming areas in Cape Town. Pot and field studies were carried out on the effects and concentrations of cadmium and lead on Phaseolus vulgaris. Field studies included collecting plant samples from the Joostenbergvlakte/ Kraaifontein farming areas and measuring the heavy metal concentrations within the different organs of the plants. Pot experiments were carried out, where Phaseolus vulgaris var. Contender were grown and then heavy metals were administered to these plants together with two heavy metal mitigation techniques, precipitation with phosphate and mobilisation with EDTA to see if they were successful in combating heavy metal pollution.Samples taken from farms in the Joostenbergvlakte/ Kraaifontein area revealed that cadmium, lead and zinc concentrations were higher than the legal standard in the edible fruits. In the pot experiment, results revealed that cadmium reduced the chlorophyll index as well as the shoot fresh mass and changes in mineral uptake were seen. Lead did not affect growth or the chlorophyll index. The high cadmium treatment resulted in a marked increase in sodium concentration in the shoots. The phosphate treatments and EDTA treatments both resulted in increased cadmium concentrations in the roots and shoots. The higher phosphate and lead treatments also reduced lead concentrations in the roots. Low phosphate and the EDTA treatments increased the shoot sodium concentrations.