Dissertations / Theses on the topic 'Water ferns'

O aerênquima é um tecido vegetal com grandes lacunas de ar que podem ter função de circulação de gases e/ou sustentação de órgãos, estando presente nas raízes e órgãos aéreos de plantas aquáticas ou sob alagamento, podendo ainda ser formado em decorrência de algum estresse. Ceratopteris richardii é uma planta aquática, de hábito anfíbio que apresenta aerênquima em seus órgãos vegetativos. Dessa forma, esse trabalho buscou analisar a formação de aerênquima nas raízes e pecíolo desta espécie frente a uma situação de restrição hídrica e verificar sua plasticidade fenotípica. Vinte indivíduos de C. richardii foram cultivados e submetidos a um tratamento com diferentes concentrações de PEG 6000. Em todas as amostras analisadas, foi observada a formação de aerênquima. A análise qualitativa mostrou diferença entre os tratamentos, porém, a análise estatística revelou que as diferenças não são significativas para o número amostral empregado. Variações de crescimento do esporófito revelaram que a espécie de estudo modificou algumas características de desenvolvimento em resposta a restrição hídrica. Tais resultados revelam importantes características para esta espécie, que parece aclimatar-se a situação de estresse a qual foi submetida. Com base nisso, sugere-se ampliar estes estudos para elucidar questões relacionadas a formação de aerênquima e o ambiente, seja para esta espécie ou de outro grupo taxonômico.
Aerenchyma is a plant tissue with large air gaps that may have gas circulation function and / or sustain organs. This structure is present in roots and aerial organs of water plants and in plants under flooding it may also be formed during some stress. Ceratopteris richardii is an aquatic plant, with amphibious habit that has aerenchyma in their vegetative organs. Thus, the aim of this study is analyze the aerenchyma formation in roots and stem of this specie under water restriction situation and verify their phenotypic plasticity. Twenty specimen of C. richardii were cultured and subjected to treatment with different concentrations of PEG 6000. In all samples, were observed aerenchyma formation. Qualitative analysis showed differences among treatments, however, the statistical analysis revealed that the differences are not significant for the sample size. Sporophyte growth variations revealed that the specie of study modified some growth characteristics in response to water restriction. These results reveal important characteristics for C. richardii, which seems to acclimatize the stress situation which has submitted. On the base that, it is suggested further studies to become clearer the relation between aerenchyma formation and environment, even to either this species or another taxonomic group.

Thesis (MTech (Horticultural Sciences)--Cape Peninsula University of Technology, 2012
This study evaluated the effects of different combinations of Hoagland’s solution and Azolla filiculoides on Beta vulgaris subsp. cycla ‘FORDHOOK GIANT’ grown in different hydroponic nutrient solutions. These solutions were comprised of a full Hoagland’s solution and a Hoagland’s solution minus nitrogen solution and amalgamations of these with Azolla respectively. The objectives were to assess the effects of different combinations of Hoagland’s solution and A. filiculoides on uptake of nitrogen and other nutrients, photosynthesis, chlorophyll content, growth and development in B. vulgaris grown in hydroponic cultures. The treatments were made up of 1) Hoagland’s minus N solution (as the control), 2) A. filiculoides plus Hoagland’s minus N solution, 3) A. filiculoides plus a full Hoagland’s solution and 4) full Hoagland’s solution. Each treatment was replicated 4 times. Nutrient uptake was measured at 4 and 8 weeks into the experiment. Photosynthesis was measured by analysing the photosynthetic rate, stomatal conductance, intercellular CO2 concentration and the evapotranspiration rate of B. vulgaris on a weekly basis. Chlorophyll content was determined by analysing the samples at 4 and 8 weeks. Growth and development was determined by measuring plant height, leaf number, leaf colour, fresh weight and dry weight. Plant height, leaf number and leaf colour on a biweekly intervals, while fresh and dry weight were analysed at 4 and 8 weeks into the experiment. In this study, the most favourable results were attained by the full Hoagland’s solution. This treatment produced plants with the highest nutrient uptake, photosynthesis, chlorophyll content and best growth and development. Preceding this was the Azolla plus full Hoagland’s solution, followed by the Azolla plus Hoagland’s minus nitrogen solution. The poorest results were noted in the control (Hoagland’s minus nitrogen solution) as all the tested parameters in this treatment were the lowest. In this study, Azolla plus Hoagland's minus N solution treatment produced significant growth in B. vulgaris. Although nitrogen was not applied in this treatment, there was improved nitrogen content in B. vulgaris organs. It is postulated that, probably, Azolla released the fixed nitrogen in its surrounding environment making it available to B. vulgaris hence improving N uptake and growth. This implies that there was a synergistic effect from Azolla–Anabaena symbiosis. More studies to understand the mechanisms involved in improving the plant growth are recommended.

In Mozambique, establishment of aquatic weeds has been enhanced through the increased enrichment of water bodies by nutrient runoffs from human and agricultural wastes that lead to an increase in nitrate and phosphate in the water. The aquatic weeds, water hyacinth (Eichhornia crassipes), red water fern ( Azolla microphylla), water lettuce (Pistia stratiotes) and salvinia (Salvinia molesta) were found in most watercourses in Mozambique and are becoming aggressive in some watercourses, especially in the Umbeluzi and Incomati rivers. Farmers and people living along the rivers are aware of the negative impact of the water weeds because the large mats of weeds cause loss of shoreline and navigability along the rivers. Other commonly perceived effects of aquatic invasive plants in Mozambique rivers include: reduced navigable surface area; difficulties for fishermen, which reduces income; increased prevalence of insects and insect-borne disease, and decreased aesthetic value. The methods currently used for the control and management of the aquatic weeds are mechanical and manual control. Both methods are costly, time consuming, and only provide a short-term solution to the problem. The study found that the weevils Neochetina eichhorniae and N. bruchi were effective biological control agents in the study area but their impact is too gradual compared to the aggressive proliferation of water hyacinth. The one year lab-experiment clearly demonstrated that the water lettuce weed had a significant impact on the recruitment of macro-invertebrates to the artificial substrates, and water lettuce contributed to the reduction of oxygen in the water and consequent reduction of macro-invertebrate abundance and diversity. The biodiversity recovered at the same time in the pools containing water lettuce controlled by N. affinis and water lettuce controlled by herbicide, but richness and diversity of macro-invertebrates was higher in the water lettuce controlled by N affinis during the first sampling occasion compared to the water lettuce in pools controlled by herbicide, where macro-invertebrates increased only when DO levels recovered after water lettuce mat decay. The number of taxa recorded in this study is an indication of the significance of macro-invertebrates in an aquatic environment. This therefore emphasizes the need for more research efforts into macrophyte and macro-invertebrate associations in the aquatic system to better understand the implications of habitat modification arising from human activities. It will also enable us to be better equipped with a more appropriate ecological understanding for aquatic resources management.

Fens are increasingly recognised as important habitats in terms of biodiversity, and this has been formalised in recent legislation (EC Habitats Directive, 92/43/EEC). The influence of groundwater and surface water inputs on the fen habitat increases its vulnerability to water pollution, particularly from nutrients. Despite the conservation importance and potential vulnerability of the habitat, fens have not been widely studied in Scotland, in terms of extent, location, sensitivity to increased nutrient inputs, or in comparison to similar European sites. This study found that fens were widespread throughout mainland Scotland, and that basin fens were the most commonly occurring fen type, representing 43% of the 355 sites assessed. A survey of 18 basin fens found that 72% were potentially vulnerable to elevated nutrient inputs, being surrounded by improved/modified land. Despite this, only four sites showed greater nutrient concentrations in sub-surface water samples or water inputs. There was, however, a significant amount of variation in hydrochemistry between the sites. Detailed studies further assessed spatial and temporal variations in hydrochemistry, and associated hydrologic regimes on two similar basin fens, one in an agricultural catchment, the other surrounded by unimproved grassland. Spatial patterning of vegetation was associated with both base-richness and nutrient concentrations of subsurface water, and the frequency of water inundation. General relationships between the six fen vegetation types and the observed hydrological and hydrochemical variation were presented.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho teve como objetivo avaliar a quantidade de calda de pulverização depositada na água e em folhas de Eichhornia crassipes (Mart.) Solms, Salvinia auriculata Aubl e Pistia stratiotes L. em condições variáveis de arranjos populacionais e dois tipos de pontas de pulverização (ConeJet TXVK-8 e TeeJet DG 11002 VS). Para tanto, foi conduzido um experimento em caixas d água composto por três Situações distintas. Na Situação Aguapé, além da proporção de dominância total correspondente à cobertura de 100% da caixa d água pelas plantas de aguapé, foram utilizados os arranjos (ou proporções) com as espécies de salvinia ou alface d água a 75%:25%, 50%:50%, 25%:75%. Adotou-se as mesmas proporções na Situação Salvínia e na Situação Alface d água, sendo que cada Situação foi determinada pela predominância total de salvínia ou alface d água, respectivamente, na caixa d água. Uma densidade tripla, onde as três espécies foram igualmente dispostas na proporção de 33,33%, foi utilizada como testemunha. Soluções dos corantes Amarelo Tartrasina FDC-5 a 3.500 ppm e Azul Brilhante FDC-1 a 1.000 ppm foram utilizados como traçadores para as pontas TXVK-8 e DG 11002VS, respectivamente. A pulverização de ambas soluções foram efetuadas na mesma unidade experimental, com um intervalo de 30 minutos entre si, através de um pulverizador costal pressurizado com CO2 e calibrado de modo a proporcionar um volume de aplicação aproximado de 200 L/ha. Amostras de água dos reservatórios foram coletadas antes e após as aplicações com o objetivo de avaliar a quantidade de calda de pulverização que não atingiu o alvo. Imediatamente após a coleta da 2 água, as plantas presentes nos reservatórios foram lavadas com água destilada até remoção total dos corantes depositados nas folhas. Placas de plástico contendo...
The present research had as objective to quantify the spray deposition on water and leaves of water hyacinth (Eichhornia crassipes (Mart.) Solms), water fern (Salvinia auriculata Aubl.) and water lettuce (Pistia stratiotes L.) according to various population arrangements and two nozzle type (ConeJet TXVK-8 and TeeJet 11002VS). The trial was carried out under reservoirs conditions using three different Situations. At Water hyacinth Situation, besides the total dominancy proportion equivalent to 100% of reservoir covering by water hyacinth plants, it was used three others combinations involving water hyacinth and water fern or water lettuce plants, as following: 75%:25%, 50%:50% and 25%:75%. The same combinations were also used at Water Fern Situation and Water Lettuce Situation, being each Situation determined by total dominancy of water fern or water lettuce in the 4 reservoirs, respectively. A triple ratio, where the three species were equally disposed at proportion of 33,33%, was used as check. Dye solutions of FD&C Yellow n. 5 at 3,500 ppm and FD&C Blue n. 1 at 1,000 ppm were used as spraying tracers for TXVK-8 and DG 11002 VS nozzles, respectively. Both solutions were sprayed at same plot within at 30 minutes interval each one through a CO2 pressured backpack knapsack calibrated to delivery a spray volume around 200 L/ha. Samples of reservoirs water were taken before and after sprays in order to evaluate the carrier quantity that not reaches the target. After that, the plants present at reservoirs were washed with distillated water until totally dyes removal deposited on the leaves. Plastic dishes containing 20 mL of distillated water were disposed in each experimental plot in order to check the spray efficacy and possible drift losses. Absorbance measures at 427 and 630 nm of wavelength were procedures... (Complete abstract, click electronic access below)

The removal of lead from aqueous solution and lead-acid battery manufacturing waste-water by the non-viable biomass of the water fern Azolla filiculoides was investigated in both batch and column reactors. The maximum lead uptake by the Azolla biomass at a pH value of approximately 5, was found to be 100 mg lead/g biomass from aqueous solution. Lead removal varied from 30% of the initial lead concentration at pH 1.5 to approximately 95% at pH values of 3.5 and 5.6. Lead removal from aqueous solution decreased to 30% of the initial lead concentration if the lead concentration was initially over 400 mg/l. At initial lead concentrations of less than 400 mg/l, percentage lead removal was found to be over 90% of the initial lead concentration. Lead removal remained at approximately 90% between 10°C and 50°C. Biomass concentration (4-8 mg/l) had little effect on lead removal. The presence of iron (Fe) and lead, copper (Cu) and lead or all three metal ions in solution at varying ratios to each other did not appear to have any significant effect on lead removal. Percentage lead, copper and iron removal from aqueous solution was 80-95, 45-50 and 65-75% respectively for the different multiple-metal solutions studied. No break-through points were observed for lead removal from aqueous solutions in column reactors, with initial lead concentrations of less than 100 mg/l at varying flow rates of 2, 5 and 10 ml/min. This suggested that flow rate, and therefore retention time, had little effect on percentage lead removal from aqueous solution, which was more that 95%, at low initial lead concentrations (less than 100 mg/l). At initial lead concentrations of 200 mg/l or more, an increase in flow rate, which equates to a decrease in column retention time, resulted in break-through points occurring earlier in the column run. Percentage lead removal values, from lead-acid battery efiluent in column systems, of over 95% were achieved. Desorption of approximately 30% and 40% of bound lead was achieved, with 0.5 M HNO₃ in a volume of 50 ml, from two lead-acid battery. Repeated adsorption and desorption of lead by the Azalia biomass over 10 cycles did not result in any decrease in the percentage lead removal from effluent, which strongly suggested that the Azalla biomass could be re-used a number of times without deterioration in its physical integrity, or lead removal capacity. No evidence of deterioration in the Azolla biomass's physical integrity after 10 successive adsorption and desorption procedures was observed using scanning electron microscopy. The Azolla filiculoides biomass was, therefore, found to be able to effectively remove lead from aqueous solution and lead-acid battery effluent repeatedly, with no observed reduction in it's uptake capacity or physical integrity.

Orientador: Dagoberto Martins
Banca: Robinson Antonio Pitelli
Banca: Gerson Augusto Gelmini
Banca: Mario Sergio Tomazela
Banca: Marcus Barifouse Matallo
Resumo: Este trabalho teve como objetivo avaliar a quantidade de calda de pulverização depositada na água e em folhas de Eichhornia crassipes (Mart.) Solms, Salvinia auriculata Aubl e Pistia stratiotes L. em condições variáveis de arranjos populacionais e dois tipos de pontas de pulverização (ConeJet TXVK-8 e TeeJet DG 11002 VS). Para tanto, foi conduzido um experimento em caixas d’água composto por três Situações distintas. Na Situação Aguapé, além da proporção de dominância total correspondente à cobertura de 100% da caixa d’água pelas plantas de aguapé, foram utilizados os arranjos (ou proporções) com as espécies de salvinia ou alface d’água a 75%:25%, 50%:50%, 25%:75%. Adotou-se as mesmas proporções na Situação Salvínia e na Situação Alface d’água, sendo que cada Situação foi determinada pela predominância total de salvínia ou alface d’água, respectivamente, na caixa d’água. Uma densidade tripla, onde as três espécies foram igualmente dispostas na proporção de 33,33%, foi utilizada como testemunha. Soluções dos corantes Amarelo Tartrasina FDC-5 a 3.500 ppm e Azul Brilhante FDC-1 a 1.000 ppm foram utilizados como traçadores para as pontas TXVK-8 e DG 11002VS, respectivamente. A pulverização de ambas soluções foram efetuadas na mesma unidade experimental, com um intervalo de 30 minutos entre si, através de um pulverizador costal pressurizado com CO2 e calibrado de modo a proporcionar um volume de aplicação aproximado de 200 L/ha. Amostras de água dos reservatórios foram coletadas antes e após as aplicações com o objetivo de avaliar a quantidade de calda de pulverização que não atingiu o alvo. Imediatamente após a coleta da 2 água, as plantas presentes nos reservatórios foram lavadas com água destilada até remoção total dos corantes depositados nas folhas. Placas de plástico contendo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The present research had as objective to quantify the spray deposition on water and leaves of water hyacinth (Eichhornia crassipes (Mart.) Solms), water fern (Salvinia auriculata Aubl.) and water lettuce (Pistia stratiotes L.) according to various population arrangements and two nozzle type (ConeJet TXVK-8 and TeeJet 11002VS). The trial was carried out under reservoirs conditions using three different Situations. At Water hyacinth Situation, besides the total dominancy proportion equivalent to 100% of reservoir covering by water hyacinth plants, it was used three others combinations involving water hyacinth and water fern or water lettuce plants, as following: 75%:25%, 50%:50% and 25%:75%. The same combinations were also used at Water Fern Situation and Water Lettuce Situation, being each Situation determined by total dominancy of water fern or water lettuce in the 4 reservoirs, respectively. A triple ratio, where the three species were equally disposed at proportion of 33,33%, was used as check. Dye solutions of FD&C Yellow n. 5 at 3,500 ppm and FD&C Blue n. 1 at 1,000 ppm were used as spraying tracers for TXVK-8 and DG 11002 VS nozzles, respectively. Both solutions were sprayed at same plot within at 30 minutes interval each one through a CO2 pressured backpack knapsack calibrated to delivery a spray volume around 200 L/ha. Samples of reservoirs water were taken before and after sprays in order to evaluate the carrier quantity that not reaches the target. After that, the plants present at reservoirs were washed with distillated water until totally dyes removal deposited on the leaves. Plastic dishes containing 20 mL of distillated water were disposed in each experimental plot in order to check the spray efficacy and possible drift losses. Absorbance measures at 427 and 630 nm of wavelength were procedures... (Complete abstract, click electronic access below)
Doutor

The aims of the project were twofold. The initial objective of the study, based on previous results, was to develop an economically viable methodology for immobilizing yeast cells for the treatment of heavy metal-laden waste water. The non-viable yeast cross-linked by 13% (w/v) formaldehyde/1N HNO₃ exhibited satisfactory mechanical strength and rigidity in a continuous-flow column operation. No apparent disruption of the biomass after repeated use was observed. The cost of immobilizing 1kg dry yeast pellets was estimated at less than US$I. Zn uptake capacity of FA-cross-linked pellets, on batch trials, remained similar to that of raw yeast, reflecting that the immobilizing procedure did not hinder its metal removing capacity. In column studies, cation metals were effectively removed by the yeast pellets from aqueous solution at natural pHs, and then recovered completely by washing the pellets in situ with O.1M HCl. The recovered metals were concentrated in such small volumes that recycling or precipitation of them was facilitated. The metal uptake capacity of the regenerated biomass remained constant in comparison with cycle 1, indicating that reuse of the yeast would be possible. In the case of Cr⁶⁺, a gradual breakthrough curve of Cr in the column profile was noted, with a simultaneous reduction of Cr⁶⁺ to Cr³⁺. However, Cr⁶⁺ in the effluent can be markedly minimised either by accumulation onto the biomass or reduction to its trivalent form. Desorption of bound Cr⁶⁺ with either alkali or salt could not accomplish the regeneration of the biomass. A combination of reduction and desorption with FA/HNO₃ appeared promising in regeneration of the saturated biomass at 4°C. The metal sorption capacities of the yeast pellets, on a batch or a fixed-bed system are relatively lower than that of documented sorbents. Apparently more of the yeast pellets would be required for treating a certain volume of waste effluent, than with other sorbents. Therefore Azolla filiculoides was examined as a suitable sorbent for this purpose. This constitutes the second part of the project. Azolla filiculoides, a naturally-abundant water fern, was screened for its metal sorption and recovering capacities, mechanical stability, flow-permeability and reusability. The azolla biomass appeared to have fulfilled the required mechanical criteria during the repeated sorption-desorption column operations. It is water-insoluble and appears flexible under pressure when rinsed with water. These characters are of crucial importance in a continuous-flow system since a column can be operated at high flow rates without apparent compact of the biomass and pressure loss. Therefore, immobilization of the biomass can be avoided. The sorption isotherm data, obtained from batch removal of Cr⁶⁺, showed that the sorption process was effective, endothermic and highly pH dependent. Considerable amounts of Cr⁶⁺ were accumulated at the optimum pHs of 2-2.5. Column sorption of Cr⁶⁺ at a low flow rate and pH of 2.5 showed optimum performance with a total Cr uptake of 50.4mg/g at 60% saturation of the biomass. Removal of Cr⁶⁺ from an electroplating effluent using an azolla column was deemed reasonably satisfactory, although the uptake declined slightly. Desorption of bound Cr⁶⁺ with various desorbents was incomplete, which resulted in a low regeneration efficiency of about 50%. However, removal and recovery of Cr³⁺ using the azolla column was than that of Cr⁶⁺. Desorption of Cr³⁺ from the spent biomass column was accomplished with the recovery of 80% using O.5N H₂SO₄, The regeneration efficiencies for Cr³⁺ removal were up to 90% and demonstrated that the biomass is reusable. Cation metal uptake capacities of azolla, obtained either from batch or column experiments, are reasonably high in comparison with other sorbents. The uptake of Ni or Zn ions from solution is pH dependent showing the optimum pH of around 6 to 6.5, under the current experimental conditions. The sorption kinetics for cation metals was rapid with about 80% of the bound Ni ions being taken up in the first 10 min. The character of rapid binding is extremely important in a column sorption process, especially on a large scale since it favours an optimum uptake of metals at high flow rates. The Ni or Zn uptakes in column sorption were not markedly affected when the flow rates were increased from 80mllh up to 800ml/h for the 5g biomass used. The cation heavy metals removed from waste effluents were recovered in a concentrated solution of small volume. The desorption of bound Ni and Zn ions from the saturated biomass was accomplished with either O.2N HCl or H₂SO₄ that resulted in recoveries of more than 95%. The metals recovered, in the case of Ni and Zn, are identical to that of plating agents ego nickel sulphate or chloride, so that recycling of the metals is possible. An effluent-free, closed loop of Ni or Zn treatment system was proposed, whereby the Ni or Zn ions can be recycled to the plating bath whilst the purified water is fed back to the rinse tanks. Ca and Mg ions, commonly present in the electroplating effluents, appeared to affect sorption of heavy metals by azolla when metal concentrations were relatively low, presumedly through its competitive binding for the shared sites on surfaces of azolla. The data obtained from column sorption of Ni and Zn follows the BDST model well, enabling the application of the model to predicting design parameters for scale-up of the biosorption column system. It is interesting that the values of metal uptake, expressed in molar quantities, obtained on respective single-metal solutions and the multiple metal system, are similar, implying that the mechanisms involved in the sorption of all metal cations are similar and that the binding sites on surfaces of azolla are probably shared by all cation metals. The surface of the biomass provides sites for metal binding estimated in the range of 0.45-0.57mmol/g, based on the current experiments. The biomass has a surface area of 429 m²/g and water retention of 14.3 ml/g. The functional groups on the surface of azolla were partially identified using chemical modification and metal binding comparison. Among the functional groups examined, carboxyl groups, provided by amino acids and polysaccharides, appeared to play an important role in metal cation binding. The infrared spectra of the samples support this conclusion.

This thesis examines 'improvement' of wetland commons in early modern England as a contested process of rapid environmental change. As a flagship project of agrarian improvement, drainage sought to alchemise pastoral fen commons into arable enclosed terra firma and promised manifold benefits for crown, commoners, and commonwealth alike. In practice, however, improvement schemes generated friction between the political and fiscal agendas of governors and projectors and local communities' customary ways of knowing and using wetland commons, provoking the most sustained and violent agrarian unrest of the seventeenth century. This thesis situates the first state-led drainage project in England, in the northern fens of Hatfield Level, in the context of the local politics of custom, national legal and political developments, and international movements of capital, expertise, and refugees; all of which intersected to reshape perceptions and management of English wetlands. Drawing on the analytic perspectives of environmental history, this thesis explores divergent ideas and practices generating conflict over the making of private property, reorganisation of flow, and reconfiguration of lived environments. This thesis argues that different 'environing' practices - both mental and material - distinguished what was seen as an ordered or disordered landscape, determined when and how water was understood as a resource or risk, and demarcated different scales and forms of intervention. Rival visions of the fenscape, ways of knowing land and water, and concepts of value and justice were productive of, and produced by, different practices of management, ownership, and use. Drainage disputes therefore crossed different spheres of discourse and action, spanning parliament, courtroom, and commons to bring improvement into dialogue with fen custom and generate a contentious environmental politics. In seven substantive chapters, this thesis investigates how improvement was imagined, legitimised, and enacted; how fen communities experienced and navigated rapid environmental transformation; and how political, social, and spatial boundaries were reforged in the process. By grounding improvement in the early modern fenscape, this thesis reintegrates agency into accounts of inexorable socio-economic change, illuminates ideas at work in social contexts, and deepens understandings of environmental conflict.

The potential of non-viable Azalia filiculaides for the removal of Cu and Ni from aqueous solutions and the possibility of scaling up existing lab scale Azalia column systems was investigated. The effects of factors such as metal starting concentration, pH and two metals in solution on the removal of Ni and Cu from aqueous solution by dried and crushed Azalia biomass were studied in batch systems. Aqueous solutions of Ni with starting concentrations between 1000 and 2000J.lmolll gave the most efficient Ni removal by Azalla biomass. For Cu the optimum starting concentration for adsorption was 50J.lmol/l. The adsorption capacity of both eu and Ni increased as the starting pH of the sorption media increased. The optimum pH for Ni adsorption was found at pH 7 and for Cu, at pH 5. - Awlla biomass had a higher. maximum binding capacity (qrnax) for Cu than for Ni at pH 5. The removal of both Cu allct Ni showed little or no variation with the presence another metal in solution. Kinetic studies show that both Cu and Ni adsorbed rapidly onto the Azalia biomass. The removal of Cu and Ni from aqueous solutions using non-viable Azalia biomass was investigated in a lab scale fixed-bed column and an upscaled 4L column system. The nonviable Azalla filiculaides biomass when dried and used in a column for adsorption of Cu and Ni showed good physical stability under many different conditions. Preparation of the biomass before it could be used in the columns was very simple and did not involve any significant pretreatment steps. Prolonged exposure to UV light decreases Azalia biomass capacity for Ni and Cu adsorption. Column adsorption of Cu and Ni from aqueous solutions was successfully upscaled approximately 100 times. Relative to the lab scale column, the 4L column performed better for the uptake of Cu and Ni per gram of biomass. The larger column was also able to operate at relatively higher flow rates. The biomass showed good reusability with little change in the amount of Ni adsorbed in 10 consecutive cycles. Electron micrographs showecf little or no change in the physical structure and integrity of the Azolla biomass after exposure to mineral acids, Ni solution and high flow rates over 10 consecutive adsorption and desorption cycles. As much as 80% Ni and 70 % Cu was recovered when desorption profiles were generated using O.lMHCI as a desorption agent. The 4L column system was also tested using a highly concen~rat:~ Ni plating bath solution.(Nicrolyte 1). Only 18 % of the Ni could be removed from the expended Nicrolyte 1 pla~Jng solution after treating only 25L, indicating that Azolla biomass is more suited for removal of metals from more dilute industrial effluents.

Zur Sicherung der Fischbestände muss die Aquakultur ihren Beitrag zur Weltfischversorgung weiter steigern. Solange jedoch die Fischfutter Produktion stark von der Gewinnung von Fischmehl abhängig ist, bestehen für die Aquakultur natürliche Begrenzungen und die Gefahr der Überfischung der Fischbestände bleibt erhalten. Wenn das Wachstumspotenzial der Aquakultur ausgeschöpft werden soll, müssen beträchtliche Mengen von Nährstoffeinträgen in Form von vollständigen Aquakultur-Mischfuttermitteln auf einer nachhaltigen Basis verfügbar sein. Aufgrund des gestiegenen Preises von kommerziellem Fischfutter sind Kleinproduzenten nicht in der Lage dieses zu erwerben. Daher ist es notwendig, ihnen alternatives Fischfutter zur Verfügung zu stellen. Wasserpflanzen können eine bedeutende Nahrungsquelle für herbivore- und omnivore Fische sein. Dennoch ist die Nutzung dieser Pflanzen als Zusatz für Fischfutter durch eine Reihe antinutritiver Substanzen, welche das normale Fischwachstum negativ beeinträchtigen, begrenzt. Unterschiedliche Behandlungen der Pflanzen können den Anteil an antinutritiven Substanzen reduzieren. Das Ziel dieser Dissertation war es, das nutritive Potential von Wasserpflanzen zu bestimmen. Die Wirkung der Behandlungen wie Sonnentrocknung oder Fermentierung zu bewerten und den Effekt ihrer Nutzung als Fischfutter auf das Wachstum von kultivierten Fischen zu erfassen. Dazu wurden Rationen mit einem geringen Gehalt an Fischmehl (3%) und bis zu 25% der Wasserpflanzen an die Fischspezies P. brachypomus und O. niloticus verfüttert. Die Ergebnisse der Untersuchung zeigen dass, eine ausschließlich auf aquatischen Makrophyten basierende Fütterung nicht empfehlenswert ist. Indem sie jedoch mit anderen lokal verfügbaren Agrar-Nebenerzeugnissen oder sogar mit kommerziellen Futtermitteln kombiniert werden, könnten die Futterkosten erheblich reduziert werden und bäuerlichen Kleinbetrieben eine Möglichkeit zum Wettbewerb auf den lokalen Märkten eröffnen.
It is commonly known that aquaculture needs to increase further its net contribution to the total world fish supplies. However, at present almost all farming operations, based on the use of fish feed, are highly dependent on available fishery resources for the production of fish meal, becoming a reducing activity rather than an activity suppling fishery resources. If the aquaculture growth potential is to be maintained, then considerable quantities of nutrient inputs in the form of aquafeeds will have to be available on a sustainable basis. On a long-term the small producers will be unable to depend on commercial aquafeeds based traditionally on fish meal, due to its increased price. Small-scale farmers need an alternative fish feed wherever possible based on the use of non-food grade locally feed resources, which is available in rural areas, is low-cost and is suitable for the proper growth and maintenance of native fish. Aquatic plants are considered important nutritional sources for herbivorous-omnivorous fish. However, the use of plant-derived materials as fish feed ingredient is limited by the presence of wide variety of antinutrients that affect the normal fish growth negatively; so that plants should be processed to reduce the effects of these compounds. Considering these aspects, this study assessed the nutritional potential of aquatic plants available in rural Colombia treated by sun drying and by fermentation and the effect of their use as fish feed on the growth performance of common cultured tropical fish (Piaractus brachypomus and Oreochromis niloticus) fed low fishmeal diets (3%) and until 25% of aquatic plants. The results of this study showed that a feeding exclusively based on aquatic plants is not recommendable; but to combine them with other locally available by-products of agriculture or even with commercial diets might considerably reduce feeding cost and provide to the small-scale farmers the opportunity to compete in local markets.

This dissertation concerns the narrative and theological role of divine vengeance and saintly cursing in the saints’ Lives of England and Ireland, c. 1060-1215. The dissertation considers four case studies of primary material: the hagiographical and historical writings of the English Benedictines (Goscelin of Saint-Bertin, Eadmer of Canterbury, and William of Malmesbury), the English Cistercians (Aelred and Walter Daniel of Rievaulx, John of Forde), the cross-cultural hagiographer Jocelin of Furness, and the Irish (examining key textual clusters connected with St. Máedóc of Ferns and St. Ruadán of Lorrha, whose authors are anonymous). This material is predominantly in Latin, with the exception of the Irish material, for which some vernacular (Middle Irish) hagiographical and historical/saga material is also considered. The first four chapters (I-IV) focus discretely on these respective source-based case studies. Each is framed by a discussion of those textual clusters in terms of their given authors, provenances, audiences, patrons, agendas and outlooks, to show how the representation of cursing and vengeance operated according to the logic of the texts and their authors. The methods in each case include discerning and explaining the editorial processes at work as a basis for drawing out broader patterns in these clusters with respect to the overall theme. The fifth chapter (V) frames a more thematic and comparative discussion of the foregoing material, dealing with the more general questions of language, sources, and theological convergences compared across the four source bases. This chapter reveals in particular the common influence and creative reuse of key biblical texts, the Dialogues of Gregory the Great, and the Life of Martin of Tours. Similar discussion is made of a range of common ‘paradigms’ according to which hagiographical vengeance episodes were represented. In a normative theology in which punitive miracles, divine vengeance and ritual sanction are chiefly understood as redemptive, episodes in which vengeance episodes are fatal can be considered in terms of specific sociological imperatives placing such theology under pressure. The dissertation additionally considers the question of ‘coercive fasting’ as a subset of cursing which has been hitherto studied chiefly in terms of the Irish material, but which can also be found among the Anglo-Latin writers also. Here it is argued that both bodies of material partake in an essentially shared Christian literary and theological culture, albeit one that comes under pressure from particular local, political and sociological circumstances. Looking at material on both sides of the Irish Sea in an age of reform, the dissertation ultimately considers the commonalities and differences across diverse cultural and regional outlooks with regard to their respective understandings of vengeance and cursing.

Thesis (M.S.)--University of Wisconsin--Madison, 1986.
Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 97-105).

Thesis (M.S.)--Indiana University, 2007.
Title from screen (viewed on Apr. 27, 2007) Department of Earth Science, Indiana University-Purdue University Indianapolis (IUPUI) Includes vita. Includes bibliographical references.