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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.
51

Relação da distribuição espacial de Egeria densa com as variáveis do ambiente, na represa Guarapiranga - SP / Relationship of spatial distribuition of Egeria densa with enviroment variables in Guarapiranga dam - SP

Hirata, Rafael Taminato 05 August 2011 (has links)
As macrófitas aquáticas possuem grande importância no ambiente aquático, contribuindo em diversos processos ecológicos. No entanto, o seu crescimento exagerado pode causar problemas aos sistemas aquáticos. A grande capacidade de proliferação de macrófitas aquáticas foi registrada em diversos locais da Região Metropolitana de São Paulo. A represa Guarapiranga é um dos principais mananciais dessa região e a grande colonização por Egeria densa Planchon (Hydrocharitaceae) pode afetar os usos múltiplos desse sistema. Dessa maneira, a presente dissertação apresenta no primeiro capítulo a relação de parâmetros físicos e químicos da água com a presença e a abundância de E. densa, sendo identificados dois compartimentos diferenciados pela qualidade da água e uma possível relação com a E. densa. No segundo capítulo, o efeito da declividade do litoral e da transparência da água nas populações de E. densa foi verificada por meio de regressões múltiplas. A declividade do litoral foi determinante na zonação e abundância de E. densa e a transparência da água não foi significativa para prever a abundância dessas plantas. / Macrophytes have great importance in the aquatic environment, contributing in various ecological processes. However, their excessive growth can cause problems in aquatic systems. The great proliferation capacity of macrophytes was recorded in various locations in the Metropolitan Region of São Paulo. Guarapiranga dam is one of the main sources of water for this region and the colonization of Egeria densa Planchon (Hydrocharitaceae) can affect the multiple uses of this system. Thus, the first chapter of this dissertation relates the physical and chemical parameters of water in the presence and abundance of E. densa, identifying two different compartments for water quality and a possible relationship with E. densa. In the second chapter, the effect of the littoral slope and water transparency in populations of E. densa was verified by multiple regressions analysis. The littoral slope was a determining factor in zonation and abundance of E. densa and water clarity was not significant to predict the abundance of these plants.
52

Matéria seca e acúmulo de nutrientes no aguapé utilizado para fitorremediação em águas residuárias de suinocultura /

Spósito, Thadeu Henrique Novais January 2018 (has links)
Orientador: Marcelo Carvalho Minhoto Teixeira Filho / Resumo: As águas residuárias de suinocultura (ARS) são consideradas um grande problema de cunho ambiental. Porém o aguapé (Eichhornia crassipes) parece ter uma capacidade de adaptação em meios com alta concentração da ARS, o que pode ser interessante para diminuir os nutrientes e as cargas orgânicas das ARS, cujo destino são mananciais ou até mesmo lagoas conhecidas como sumidouros, causando problemas ambientais, como a eutrofização. Neste sentido, objetivou-se analisar o polimento de água residuária de suinocultura em diferentes concentrações, por meio do cultivo de aguapé, determinou-se a concentração de elementos químicos presentes na ARS, assim como o acúmulo destes elementos na matéria seca e produção desta macrófita. O experimento foi conduzido na área experimental da ETEC (Colégio Agrícola) de Presidente Prudente - SP. Utilizou-se o delineamento experimental inteiramente casualizado, com parcelas subdivididas e cinco repetições. As parcelas constituíram de três tratamentos (água potável “Testemunha”, diluição de 50% ARS e 100% ARS) e subparcelas com cinco períodos de coleta da ARS para análise química [0 (caracterização), 7, 14, 21 e 28 dias], sendo a coleta das plantas de aguapé realizada aos 28 dias, junto a última coleta da ARS. O cultivo de aguapé em 100% de ARS proporcionou maior absorção de nutrientes, desenvolvimento e acúmulo de matéria seca desta macrófita aquática, reduzindo gradativamente conforme vai diminuindo a concentração da ARS. Recomenda-se o cultivo do aguap... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Swine wastewater (SWW) is considered to be a major environmental problem, but water hyacinth (Eichhornia crassipes) seems to have a capacity for adaptation in environments with high concentration of the same, which may be interesting to reduce nutrients and loads organic matter of this material, the destination of which are fountains or even ponds known as sinks, causing environmental problems such as eutrophication. In this sense, the aim of this study was to analyze the polishing SWW in different concentrations, by the E. crassipes crop, was determined the concentration of chemical elements present in the SWW, as well as the accumulation of these elements in the dry matter and production of this macrophyte. The experiment was conducted in the experimental area of the ETEC (Agricultural College) of Presidente Prudente - SP, Brazil. We used the fully randomized experimental design with split plots and five replications. The plots consisted of three treatments ("Witness" drinking water, 50% of SWW and 100% of SWW dilution) and the five-period ARS collection periods for chemical analysis [0 (characterization), 7, 14, 21 and 28 days]. The collection of the E. crassipes plants was carried out at 28 days along with the last SWW collection. The E. crassipes cropped in 100% SWW provided greater nutrient uptake, plant development and dry matter accumulation of this aquatic macrophyte, reducing gradually as the SWW concentration decreases. It is recommended the E. crassipes crop in SW... (Complete abstract click electronic access below) / Doutor
53

Hydrodynamics of flow-vegetation interactions at the scales of individual plant and plant patch

Siniscalchi, Fabio January 2012 (has links)
No description available.
54

The uptake of heavy metals by aquatic macrophytes and the development of microsampling analytical techniques

Bateman, Mark J. January 1999 (has links)
This thesis reviews literature relating both to the treatment of metal rich wastewaters by the use of constructed wetlands and the use of slurry analytical procedures for the determination of heavy metals in environmental micro-samples. A survey of metal contaminated wetland sites showed that aquatic plants maintain low levels of metals in aerial parts despite some very elevated sediment metal concentrations and extreme acidity. A series of greenhouse trials investigated the uptake of metals into aerial sections of Typha, Phragmites and Equisetum in long term hydroponic experiments. Phragmites was shown to accumulate zinc to a higher level than Typha. The toxicity of zinc supplied in the nutrient solution at 5 mg.dm-3 over long periods was found to limit the viability of such non-sediment based systems. A reliable routine analytical procedure was developed along with a program of quality control for the study of metal uptake into aquatic plants. A micro sampling technique, eminently suited for the analysis of small plant sections was developed. This technique uses ozone to ash the plant samples at a low temperature and following suspension in a liquid medium provides a sample ready for slurry determinations by a variety of analytical instrumentation. It is proposed that this method may also be suitable for the determination of metals in individual invertebrates and other zoological micro-samples as well as potential applications in the medical field.
55

Internal pressurisation and convective flow in two species of emergent macrophyte; Typha domingensis and Phragmites australis / by Sean D. White.

White, Sean D. (Sean Darren) January 1999 (has links)
Bibliography: p. 171-181. / xxiii, 181 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The comparision of the pond and field plants suggests both species are eminently more suited to static water regime where adaptations by the plant can be made effectively to help with the problem of oxygen transport. The results also suggest that plants experience a variable and static water regime differently. / Thesis (Ph.D.), University of Adelaide, Dept. of Botany, 1999
56

Seaforms /

Wright, Karen Louise. January 1988 (has links)
Thesis (MFA)--Rochester Institute of Technology, 1988. / Includes bibliographical references (leaf 51).
57

Respiratory adaptations of secondarily aquatic organisms : studies on diving insects and sacred lotus

Matthews, Philip Gordon Douglas. January 2007 (has links)
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, Discipline of Ecological and Evolutionary Biology, 2008. / "December 2007" Bibliography: leaves 117-123. Also available in print form.
58

The effects of water flow, pH and nutrition on the growth of the native aquatic plant, Aponogeton elongatus /

Crossley, Mark Norman. January 2002 (has links) (PDF)
Thesis (M.Phil.)--University of Queensland, 2003. / Includes bibliography.
59

Impact of aquatic macrophytes on Escherichia coli concentrations at recreational inland beaches

Leewis, Mary-Cathrine Christina Elaine, January 2006 (has links)
Thesis (M.S.)--Northern Michigan University, 2006. / Includes bibliographical references.
60

Relação da distribuição espacial de Egeria densa com as variáveis do ambiente, na represa Guarapiranga - SP / Relationship of spatial distribuition of Egeria densa with enviroment variables in Guarapiranga dam - SP

Rafael Taminato Hirata 05 August 2011 (has links)
As macrófitas aquáticas possuem grande importância no ambiente aquático, contribuindo em diversos processos ecológicos. No entanto, o seu crescimento exagerado pode causar problemas aos sistemas aquáticos. A grande capacidade de proliferação de macrófitas aquáticas foi registrada em diversos locais da Região Metropolitana de São Paulo. A represa Guarapiranga é um dos principais mananciais dessa região e a grande colonização por Egeria densa Planchon (Hydrocharitaceae) pode afetar os usos múltiplos desse sistema. Dessa maneira, a presente dissertação apresenta no primeiro capítulo a relação de parâmetros físicos e químicos da água com a presença e a abundância de E. densa, sendo identificados dois compartimentos diferenciados pela qualidade da água e uma possível relação com a E. densa. No segundo capítulo, o efeito da declividade do litoral e da transparência da água nas populações de E. densa foi verificada por meio de regressões múltiplas. A declividade do litoral foi determinante na zonação e abundância de E. densa e a transparência da água não foi significativa para prever a abundância dessas plantas. / Macrophytes have great importance in the aquatic environment, contributing in various ecological processes. However, their excessive growth can cause problems in aquatic systems. The great proliferation capacity of macrophytes was recorded in various locations in the Metropolitan Region of São Paulo. Guarapiranga dam is one of the main sources of water for this region and the colonization of Egeria densa Planchon (Hydrocharitaceae) can affect the multiple uses of this system. Thus, the first chapter of this dissertation relates the physical and chemical parameters of water in the presence and abundance of E. densa, identifying two different compartments for water quality and a possible relationship with E. densa. In the second chapter, the effect of the littoral slope and water transparency in populations of E. densa was verified by multiple regressions analysis. The littoral slope was a determining factor in zonation and abundance of E. densa and water clarity was not significant to predict the abundance of these plants.

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