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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.
301

Desenvolvimento de mudas de pinhão manso (Jatropha  curcas L.) em tubetes e submetidas a diferentes níveis de déficit hídrico. / Development of seedlings of physic nut (Jatropha curcas L.) in plastic tubes and submitted to different levels of water deficit

Cícero Renê Almeida Barboza Júnior 31 January 2012 (has links)
Com a crescente procura por alternativas para suprir energeticamente o mundo, cada vez mais, fontes mais limpas e renováveis estão sendo utilizadas. No Brasil, a produção de óleos vegetais visando a geração de energia (biodiesel) ainda é incipiente. Dentre as diferentes espécies de oleaginosas, o pinhão manso (Jatropha curcas L.) vem se destacando como uma ótima alternativa no fornecimento de matéria prima para a produção de biodiesel. Informações sobre essa cultura ainda são escassas, principalmente no Brasil, onde há pouco tempo foram iniciadas as pesquisas. A necessidade de informações locais também ressalta a importância da pesquisa com o Pinhão Manso. Com base nessas necessidades, o objetivo desse experimento foi analisar a viabilidade técnica da produção de mudas irrigadas de pinhão manso por sistema de subirrigação e desenvolver um sistema automatizado de manejo. O controle da irrigação foi realizado a partir da variação de peso dos tubetes com as mudas, devido a perda de água por evapotranspiração. No processo de controle dos pesos foram utilizadas células de carga, que monitoraram a variação de peso de um conjunto de tubetes denominado conjunto controle. O delineamento experimental foi em delineamento inteiramente aleatorizado, com quatro repetições. Os tratamentos avaliados foram quatro níveis de depleção da máxima capacidade de retenção de água (MCRA) apresentada pelo substrato (T1=20%, T2=40%, T3=60% e T4=80% da MCRA). Para se quantificar os efeitos dos tratamentos foram avaliadas semanalmente as seguintes características das mudas: altura e diâmetro do caule, número de folhas e área foliar, bem como a produção de matéria fresca e seca da parte aérea e do sistema radicular. Os resultados mostram que o tratamento 2 foi o que se destacou dentre os demais, produzindo mudas de melhor qualidade, com maior acúmulo de matéria seca e maior consumo hídrico. / With the growing demand for alternative energy to meet the world, increasingly more clean and renewable sources are being used. In Brazil, the production of vegetable oils aimed at producing energy (biodiesel) is still incipient. Among the different species of oleaginous plants, jatropha (Jatropha curcas L.) has emerged as a great alternative in providing raw material for biodiesel production. Information on this crop are still scarce, especially in Brazil where they recently started research. The need for local information also emphasizes the importance of research with Jatropha. Based on these needs, the aim of this experiment was to analyze the technical viability production of jatropha seedlings irrigated by subirrigation system and develop an automated system management. The irrigation control was carried out from the weight variation of the vials with the seedlings because of water loss through evapotranspiration. In the process of weight control were used load cells, which monitored the weight variation of a set of vials called the control group. The experimental design was the completely randomized with four replications. The treatments were four levels of depletion of the maximum water holding capacity (MCRA) presented by the substrate (T1=20%, T2=40%, T3=60% e T4=80% da MCRA). To quantify the effects of the treatments were evaluated weekly the following characteristics of seedlings: height and diameter of the stem, leaf number and leaf area, and the production of fresh and dry shoot and root. The results show that treatment 2 was what stood out among the others, producing higher quality seedlings with greater dry matter accumulation and increased water consumption.
302

Water insurance as climate change adaptation tool for optimization of water permits / Seguros hídricos como mecanismos de adaptação às mudanças do clima para otimizar a outorga de uso da água

Guilherme Samprogna Mohor 15 April 2016 (has links)
Recent prolonged droughts make the urgent need to revise the criteria for water use permits in Brazil, especially in basins under conflicts for water use. Mechanisms for water risks transfer are an important adaptation tool. However, in Brazil, there is no established methodology that adapts this technique to assist the water use permit instrument. Moreover, there is no water risk insurance methodology with uncertainty analysis that complements its effectiveness in reducing losses from extreme events. Hydrologic modelling is the basis for development of these tools, which carries uncertainties that must be considered in decision-making. The objectives of this project were: i) coupling climatic, hydrologic and water insurance models to evaluate the use permit decision-making; ii) analyse sensitivity of performance indicators of a water risk insurance model through the application of different hydrologic models driven by climate change projections. The methodology was applied in donor basins of the Cantareira Water Supply System, which supplies water to an important metropolitan region that showed itself vulnerable to hydrologic extremes in the last years. The MHD-INPE and SWAT hydrologic models were applied, driven by the Eta- HadGEM2-ES climate model projections to characterize the future hydrologic regime in the region and also to compare the structure, performances and gaps of the models. Structural differences are most likely the greater responsible for the results differences, though no result could be identified as \"more certain\". With the hydrologic models outputs fitted the the Gumbel extreme values distribution, a proposed insurance fund simulator, MTRH-SHS, was run with 100 equiprobable scenarios of 50-year annual low-flow events to calculated an optimized premium capable of paying all indeminities of hydrologic drought. Besides the future hydrologic regimes, water demand scenarios were also tested. The optimized premiums were compared to the local GDP to assess the apparent affordability of the insurance, with some premium representing up to 0.54% of local GDP, but in the water resources management framework, the decision should be made collectively by several actors within the basin's committee. / Recentes estiagens fazem reconsiderar a necessidade de aperfeiçoar critérios de outorga de água no Brasil, especialmente em bacias com conflitos pelo uso da água. Seguros (transferência de risco) são importante ferramenta de adaptação. Contudo, no Brasil ainda não há metodologia consolidada que adapte esta técnica para auxiliar o instrumento de outorga de recursos hídricos. Ainda, não há metodologia de seguros hídricos com análise de incertezas, complementando sua efetividade ao reduzir os prejuízos advindos de eventos extremos. Modelos hidrológicos são a base de desenvolvimento destas ferramentas e carregam incertezas que devem ser integralizadas nos processos de decisão. Os objetivos deste projeto foram: i) acoplar modelos: climático, hidrológico e de seguros hídricos para a avaliação do processo de decisão de outorga; ii) realizar análise de sensibilidade dos indicadores de desempenho de modelo de seguros hídricos com diferentes modelos hidrológicos sob cenários de mudanças do clima. A metodologia foi aplicada nas bacias doadoras do Sistema Cantareira, que abastece importante região metropolitana e mostrou-se vulnerável a extremos hidrológicos nos últimos anos. Os modelos hidrológicos MHD-INPE e SWAT foram aplicados, forçados pelas projeções climáticas do modelo Eta-HadGEM2-ES a fim de caracterizar o regime hidrológico future na região, assim como comparar a estrutura, diferenças e performances dos modelos hidrológicos. As diferenças estruturais são provavelmente as maiores responsáveis pela diferença nos resultados, embora não seja possível apontar um modelo "melhor" que o outro. As saídas dos modelos foram ajustadas na distribuição de Gumbel e utilizada no modelo proposto de simulação de fundo de seguros, MTRH-SHS, rodado com 100 séries equiprováveis de 50 anos de eventos mínimos anuais. A cada série um prêmio otimizado é calculado para cobrir todas as indenizações de seca hidrológica. Além das projeções hidrológicas, cenários de demanda foram testados. Os prêmios otimizados foram comparados com o PIB local para demonstrar a viabilidade em implementar o seguro. Os valores representam até 0.54% do PIB local em um dos casos, mas na gestão de recursos hídricos, a decisão final pela implementação deve ser feita no âmbito do comitê de bacias por múltiplos atores.
303

Análise de desempenho térmico de telhas de fibrocimento tratadas com revestimentos brancos e submetidas à aspersão de água / Analysis thermal performance of fiber cement tiles treated with white coatings and submitted to water spraying

Teixeira, Carla Fernanda Barbosa, 1977- 06 May 2013 (has links)
Orientador: Lucila Chebel Labaki. / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-23T11:44:35Z (GMT). No. of bitstreams: 1 Teixeira_CarlaFernandaBarbosa_D.pdf: 4846787 bytes, checksum: a2bbec42880bcecfdd43b8f22e0fecf7 (MD5) Previous issue date: 2013 / Resumo: A busca por materiais, tecnologias ou meios que tornem as edificações mais eficientes energeticamente é uma meta de pesquisadores, educadores e projetistas não só no Brasil, mas também no mundo. O uso de cores claras em coberturas tem sido bastante estudado como estratégia de resfriamento para climas quentes. Este trabalho tem como objetivo analisar o desempenho térmico de acabamentos de cor branca em coberturas e estimar o consumo de energia para um ambiente com cobertura branca. Adicionado ao emprego de acabamentos refletivos, empregou-se a aspersão de água pluvial sobre os acabamentos empregados. A caracterização do desempenho de acabamentos de tinta na cor branca requisitou a realização de ensaios para determinar as características dos acabamentos nas superfícies das telhas: emissividade, refletância solar e absorção de água aspergida. Para tanto, a revisão bibliográfica do assunto foi necessária para investigar metodologias aplicadas in pesquisas realizadas no mundo. Em telhas de fibrocimento foram aplicadas tintas imobiliárias comuns (de diferentes composições químicas, porém de mesma cor branca) associadas à aspersão de água e expostas a intempéries ambientais. Temperaturas superficiais internas das telhas e variáveis meteorológicas foram coletadas e analisadas, conjuntamente com dados dos ensaios de refletância solar, emissividade térmica e absorção de água na superfície das telhas de fibrocimento. Os resultados para a técnica refletiva de acabamentos de cor clara comprovaram as expectativas, no entanto, quando esta técnica foi associada à aspersão de água nas superfícies, os resultados foram otimizados. Esses resultados ilustram a necessidade da atenção na especificação do tipo de acabamento branco. Estimou-se, através de simulação térmica, a influência do acabamento branco no consumo de energia anual de um ambiente. O propósito deste trabalho é contribuir com informações adicionais em relação ao acabamento de cor branca, atenuando as temperaturas da cobertura de uma edificação, como demonstrar que o emprego de água pluvial pode atenuar o volume escoado pelas vias na estação chuvosa / Abstract: The search for materials, technologies and ways that can get constructions more energy efficient has been a concern of researches, educators and designers not only in Brazil, but also in the world. The use of light colors on roofing has been studied a lot; like cooling strategy for hot climates. The aim of this work is to analyze thermal performance of white coatings on roofing and to estimate energy savings in a room with white coating on roofing. Evaporative cooling, added to reflective cooling, was used through rain-water spraying on coating surfaces. Some testing on coatings as thermal emissivity, solar reflectance and absorption of sprayed water were requested for characterization of coatings thermal performance. In consequence of that literature review related to these themes was necessary to investigate methodologies applied in researches which have been done in the world. Commercial and ordinary paintings (of different chemical compositions, but with same color: white) were applied on fiber cement tiles in association to water spraying in weather conditions. Inside-surface temperatures and meteorological data were collected and analyzed together with solar reflectance, thermal emissivity and water absorption by tile coatings. Results of reflective technique proved expectations and illustrated that some attention is requested to choose the kind of white painting. However, when these coatings received water spraying on surfaces, they got the best results. The white coatings influences were considered through an annual thermal simulation energy saving. This work has the purpose to contribute with existing additional information in relation to white painting available, in order to get less roofing temperatures as well as to show that the rain water usage could be a tool for decreasing drained water on streets in rainy season / Doutorado / Arquitetura, Tecnologia e Cidade / Doutora em Arquitetura, Tecnologia e Cidade
304

A shift from extensive to intensive livestock production system in Uruguay : Driver of local changes in water-related ecosystem services?

Ran, Ylva January 2012 (has links)
Livestock production is one of the largest and fastest growing agricultural subsectors in the world, contributing almost 40 % of agricultural GDP. The present global trend of livestock intensification affects water demand, resulting in local alterations of hydrological features. This study quantifies water requirements for livestock production and links them to local changes in water-related ecosystem services (WRES). It examines the present situation in Uruguayan beef production as it undergoes an intensification process by analyzing three systems: traditional extensive production, mixed systems and intensive production.Mixed production systems are most water-effective in terms of water requirement. However, extensive production has the least negative long-term effects on the studied WRESs: soil productivity, erosion control and grass, crop and livestock production. Intensive systems contribute the largest negative impacts on soil productivity due to management practices, e.g. continuous cropping and fertilizer application (which is also costly). However, intensification also increases short-term positive effects on crop and livestock production. Mixed systems offer opportunities to increase livestock production, water use efficiency and mitigate soil degradation. However, a threshold value to avoid an undesirable regime shift in soil productivity remains to be determined.This framework developed herein, maps and quantifies local ecosystem effects associated with livestock production from a water perspective. It required simplifications and thus needs further improvements to be of practical use as a tool for best management practices of livestock production. Such tools can assist decision-makers in Uruguay on how to manage multiple ecosystem services in an agricultural landscape and enhance the provision of desired ES without degrading other key ecosystem processes, goods and services. For sustainable production of livestock in Uruguay, one should consider if the tradeoff between long-term negative impacts of intensification on regulating services is justifiable in the context of the short-term economic gains in provisioning services.
305

Synthesis of a model for optimising a potable water treatment plant and water usage analysis in the Ugu District

Magombo, James January 2017 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Engineering, Department of Industrial Engineering, Durban University of Technology, Durban, South Africa, 2017. / Access to clean and adequate water is a universal and basic human right that feeds into the 6th of the 17 Sustainable Development Goals (SDGs). This goal aims at ensuring availability and sustainable management of water and sanitation for all. Clean water is referred to as potable water, which is safe for human consumption and offer low risk of immediate or long term harm. Raw water undergoes rigorous processing which consists of coagulation, sedimentation, filtration, disinfection and storage, to produce potable water. Each module or stage consumes chemicals and energy resources and thus incurs costs. To achieve the aim of the study, which was to synthesize an optimised potable water treatment network and a water usage analysis model, the Umzinto Water Treatment Plant (UWTP) and its distribution system was used as the study area. This treatment plant is located within Umdoni, a local municipality of the Ugu District Municipality in KwaZulu-Natal Province, South Africa. This study’s objectives were fourfold and the first objective was to identify and quantify key raw water quality parameters affecting treatment at the UWTP. The second objective was to design a genetic algorithm for the potable water treatment process control. The third objective was to evaluate the Umzinto Water Distribution System’s Non-Revenue Water (NRW) while the fourth objective was to develop a model for water usage analysis. For the first objective, data for water quality parameters for the water treatment from July 2006 to June 2013 were statistically analysed. This data were collected from the UWTP’s historical records. To improve the data’s integrity it was pre-processed using cubic hermite interpolation. After the pre-processing trend lines and box plots were used to determine the parameters’ significance compared to the standard values stipulated in the South African National Standard (SANS 241). The trend lines were used to analyse the frequency of observations that were higher than the standard values according to SANS 241. The box plots were used to determine the minimum, median, maximum and mean of the data sets. The mean values for each parameter were compared to the SANS 241 value to determine their significance. The raw water quality parameters were then correlated to the chemical dosages for lime, polymer, potassium permanganate and chlorine. The key parameters selected from the correlation analysis were algal count, manganese (Mn), iron (Fe), Escherichia coli, total coliforms, colour, odour, conductivity, turbidity, suspended solids (SS), pH, temperature, total organic carbon (TOC,) and Hardness. A number of methods can be used to achieve such optimisation, including artificial neural networks, dynamic programming, linear and non-linear programming, and this study utilised a genetic algorithm as an optimisation tool to achieve the second objective of optimising water treatment at the UWTP. For the model development, data from the correlations obtained for objective 1 were used. The model was aimed at reducing the cost of chemical dosage and four chemical dosage prediction models were developed using genetic algorithms and these were then used to produce a combined chemical dosage cost prediction model. The programming interface utilised for these models was Matlab. In developing these models, the data were first pre-processed to remove outliers and fill in the blanks using a Microsoft Excel Add-in that was developed for this particular purpose. The next step involved a curve fitting exercise in Microsoft Excel 2013. Matlab was then used to code the genetic algorithm that combined and optimised the solutions obtained from the curve fittings. The results showed that genetic algorithms can be reliably used to predict the chemical dosages and hence reduce water treatment costs. After treatment, water is pumped into the distribution system for consumption. It is therefore important to ensure that all the pumped out treated water reaches the consumer. The third objective therefore assessed the NRW for the Umzinto Water Distribution System for the period between July 2013 and June 2014. The data used for this objective was provided by the Ugu District Municipality. The method used combined the top-down approach and the component-based approach. This combined approach was modified to enable the calculation of all the components that are required in a standard South African Water Balance. The results showed that the distribution system had a high value of NRW, which was 27.9% of the System Input Volume. The major component of NRW was Real Losses, that is, losses that can be mitigated by improving maintenance. The fourth objective was to develop a model for water usage analysis that would reduce the time taken to evaluate NRW and also improve the analysis of the NRW components using Microsoft Visual Basics 2012 and Microsoft SQL Server 2012 development interfaces. The Visual Basics enabled the development of a graphic user interface that was user-friendly and minimised the time taken to learn the software. The software platform developed was able to import the data required to construct a standard International Water Asssociation (IWA) Water Balance, calculate all the components of NRW, store historical data for the water distribution systems and report on a rolling year basis. A model for water usage analysis was developed and made available for usage by practitioners in Ugu District. The model was developed for the specific study area and further studies would be required in order to validate it in a different setting. The results obtained for the first objective led to the conclusion that, there was very high pollution emanating from communities and activities close to the raw water sources, especially the EJ Smith Dam. The results from the first objective were also used to determine parameters for the models developed in the second objective. From objective two it was concluded that genetic algorithms can be reliably used to predict chemical dosages and hence reduce water treatment costs. The third objective’s results showed that 27.9% of treated water pumped into the distribution system is NRW. Which is a concern because 65% of this are real losses which have maintenance related problems. The fourth objective’s results showed the practicality of designing model that could be used determine all the important components of NRW that would take time to evaluate manually. It would also store historical data for the water distribution system and report on a rolling year basis. Implementation of this software would help minimise the errors associated with manual calculation of NRW and improve the availability of data for research and analysis. From the research findings, it is recommended that the treatment plant should change the way it is dosing chemicals in the balancing tank. The method currently being used is prone to error. The analysis of NRW showed that Real Losses were a major challenge in the Umzinto Distribution System. There is need to develop a maintenance program to cater for leakage. Communities also need to be educated on the importance of reporting leakage in the network. / M
306

Diversité interspécifique de l'efficience d'utilisation de l'eau des acacias sahéliens et australiens / Inter-specific diversity of water use efficiency among sahelian and australian acacias

Konaté, Nianguiri Moussa 12 July 2010 (has links)
Le principal objectif de ce travail était de déterminer l’efficience d’utilisation de l’eau (WUE) de diverses espèces d’acacias d’origine Australienne et Sahélienne par la discrimination isotopique au niveau de la feuille (Δ13Cf) et par différentes techniques de mesure. Les acacias ont montré une forte variabilité interspécifique de Δ13Cf. Cette variabilité a été confirmée par les mesures directes d’échanges gazeux au niveau des feuilles (efficience intrinsèque d’utilisation de l’eau, Wi) et par des mesures effectuées au niveau de la plante entière (efficience de transpiration, TE). Une forte variabilité interspécifique des traits foliaires(densité stomatique DS, proportion d’azote dans les feuilles %N, surface massique SLA, assimilation nette du CO2 à la saturation Asat, conductance stomatique en vapeur d’eau à la saturation gssat) et de la croissance (ratio biomasse racinaire sur biomasse aérienne R/S) a également été constatée entre les espèces. WUE était pratiquement contrôlée par gssat.L’hypothèse selon laquelle les espèces se développant dans les zones arides présenteraient une WUE plus élevée n’a pas été vérifiée. Au contraire, les espèces des zones semi-humides ont présenté une WUE plus élevée que celles de zones semi-arides et arides. / The main objective of this work was to compare water use efficiency (WUE) among various Australian and Sahelian acacia species using isotope discrimination at leaf level (Δ13Cf) and various methods of measurement. Acacia species exhibited a large inter-specific variability of Δ13Cf. This variability was confirmed by direct leaf gas exchange measurements (intrinsic water use efficiency, Wi) and by measurement at the whole plant level (transpiration efficiency, TE). A large interspecific variability of leaf traits (stomatal density DS, leaf nitrogen concentration %N, specific leaf area SLA, net CO2 assimilation of the saturation Asat, stomatal conductance for water vapor of the saturation gssat) and growth characteristics (root shoot biomass ratio R/S) has also been reported. WUE was controlled for gssat. The hypothesis that the species from arid areas exhibit higher WUE was not confirmed. In contrast, the species from semi-wet area exhibited a higher WUE than those from semi-arid and arid zones
307

Responses of Amaranth to salinity stress

Omami, Elizabeth Nabwile 03 February 2006 (has links)
Salinity continues to be one of the world’s most serious environmental problems in agriculture. The increasing world population and urbanization are forcing farmers to utilize marginal lands as well as poor quality water. One of the strategies in dealing with salinity is growing salt tolerant plants and there has been increased need to understand the effects of salinity on crops. Owing to its high nutritive value and wide adaptability to diverse environments, amaranth is considered a promising crop for marginal lands and semiarid regions. The objective of the study was to investigate the response of amaranth to salinity stress and evaluate stress amelioration by calcium and seed priming. Salinity tolerance during germination and early seedling growth was examined for six genotypes of amaranth (Amaranthus species) at different salt concentrations ranging from 0 to 200 mM NaCl or Na2SO4. Enhancement of germination was observed at 25 mM, while increasing salt concentrations reduced the germination percentage as well as germination rate. A.tricolor and Accession ’83 were able to germinate in 200 mM NaCl while there was no germination at 200 mM Na2SO4 in all the genotypes. Overall, Accession ’83 was the most resistant and A. hybridus the most sensitive genotype, particularly at high salt concentrations. Inhibition of germination was greater in Na2SO4 than in NaCl salinity treatments. Amaranth was more salt tolerant at germination than at seedling growth. Seedling emergence, survival and growth were reduced by salinity and at much lower concentrations than at seed germination. Differences in salt tolerance were noted among the genotypes. Salinity stress was initiated at different growth stages (cotyledon stage, 2-leaf stage and 4-leaf stage) in order to determine whether tolerance of amaranth differs with the stage of development. The treatment either continued until termination of the experiment or for 14 days at each stage. Amaranth plants were less sensitive to salinity when the stress was initiated at the 4-leaf stage. Lower salt concentrations had less detrimental effects than higher concentrations when applied at the cotyledon stage. Application of low salt concentration at cotyledon stage for 14 days did not have any effect on plant growth. The results indicate that it is feasible to use saline water for growing amaranth with minimum yield losses if salt concentration, duration of exposure and time of salinization are carefully managed. Differences in salinity tolerance among amaranth genotypes were analyzed in terms of plant survival, growth, gas exchange, water use and leaf anatomical changes. A. hypochondriacus and A. cruentus showed greater tolerance to salinity since they survived in 200 mM NaCl treatment and the reduction in growth at 50 and 100 mM was lower than that of A. tricolor and Accession ’83. A. hypochondriacus and A. cruentus were more efficient water users and partitioned photosynthates towards shoot growth as opposed to the other two genotypes. Photosynthetic rate, stomatal conductance, stomatal density and apertures were reduced by salinity but were higher in A. tricolor than in A. cruentus. Salinity resulted in A. cruentus developing thicker leaves compared to A. tricolor. Productivity on saline soils can be increased by growing genotypes more tolerant to salinity. The interactive effect of salinity and water stress on amaranth plant growth was evaluated. It was found that the reduction in shoot growth was greater in plants submitted to water stress than in those submitted to salt or salt + water stress. Water use efficiency was increased while leaf water and osmotic potentials were reduced by the salinity stress treatments. In drying soil plants previously salinized had a greater degree of osmotic adjustment, so that plants were able to continue growth for a longer period compared to water stressed plants. The effect of calcium in ameliorating salt stress was investigated. Supplementary calcium, either as CaSO4 or CaCl2 ameliorated the negative effects of salinity on growth, gas exchange, membrane permeability and mineral uptake. In a separate experiment it was shown that it is feasible to mitigate the adverse effects of salinity on amaranth seed germination, seedling survival and growth by seed priming and that the positive effect of priming persisted to vegetative growth stage. Priming with CaSO4 + NaCl showed a greater positive response than priming with the individual salts. / Thesis (PhD (Plant Production andSoil Science))--University of Pretoria, 2007. / Plant Production and Soil Science / unrestricted
308

Qualidade da água drenada por coberturas verdes para fins de aproveitamento em edifício / Rainwater harvested from green roofs: water quality for non potable uses

Teixeira, Paula de Castro, 1983- 22 August 2018 (has links)
Orientador: Marina Sangoi de Oliveira Ilha / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-22T06:32:12Z (GMT). No. of bitstreams: 1 Teixeira_PauladeCastro_M.pdf: 3875486 bytes, checksum: b87c55ad6441bb98356e298937ec59f1 (MD5) Previous issue date: 2013 / Resumo: O objetivo principal desta pesquisa é avaliar a qualidade da água drenada por coberturas verdes comparativamente à água escoada por uma cobertura convencional e à água coletada diretamente da atmosfera. Para tanto, foram efetuadas sete coletas de amostras da água drenada por oito coberturas verdes e por uma cobertura cerâmica, todas instaladas em células-teste. Para a análise dos dados, foi empregado o método não paramétrico de Mann-Whitney, com grau de significância de 0,05. Quando analisadas as diferentes coberturas verdes entre si, verifica-se que não existiram diferenças significativas entre os parâmetros físicos e químicos investigados. Além disso, dentre os parâmetros de qualidade de água constantes na normalização brasileira, apenas os valores do pH e da turbidez resultaram inferiores aos valores limites estabelecidos nessa documentação. No caso da cobertura convencional, apenas a cor aparente e os parâmetros microbiológicos não atenderam aos limites estabelecidos. Assim, a água drenada de coberturas verdes deve sofrer tratamento antes do seu uso, porém, verifica-se que não há necessidades diferenciadas de tratamento em relação à água coletada pela cobertura convencional, considerando-se as exigências para a água não potável dos documentos consultados. Em geral, houve melhoria dos parâmetros de qualidade com a idade das coberturas verdes e, a partir disso, propõe-se que o aproveitamento da água ocorra após um período de tempo desde a sua instalação. Por fim, é feita uma proposta de alteração dos parâmetros de qualidade constantes na normalização, de forma a também contemplar a análise da água drenada por coberturas verdes / Abstract: The main objective of this research is to assess the quality of water drained by green roofs compared to water drained by a conventional roof and also water collected directly from the atmosphere. Thus, seven samples were collected from water drained by eight different green roofs and a ceramic cover, all installed in test cells. For data analysis, the method used was the nonparametric Mann-Whitney test, at significance level of 0.05. When the different green roofs were assessed from each other, it seems there were no significant differences among the physical and chemical parameters investigated. Moreover, among the parameters listed in Brazilian standards, only pH and turbidity values resulted lower than the limit values established in this documentation. In the case of conventional roof, only the apparent color and microbiological parameters did not meet the established limits. Thus, water drained from green roofs must undergo treatment before use; however, it does not appear to need different treatment of the water collected from conventional coverage, given the requirements for non-potable water documents consulted. In a general way, there was improvement of water quality parameters as green roofs age, and from this, it is proposed that the use of water occurs after a period of time since its installation. Finally, there is a proposal to amend the quality parameters listed in standardization, in order to also include the analysis of water drained by green roofs / Mestrado / Arquitetura e Construção / Mestra em Engenharia Civil
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Sistemas de saneamento no povoado Areia Branca situado na zona de expansão de Aracaju : percepção e práticas sustentáveis no uso da água

Passos, Karla Fabiany Santana 29 February 2016 (has links)
A great concern nowadays current is that environmental and mainly related to the themes of usos water management since his consumption, levels of quality and quantity needed for population, at the dumping of waste arising from its use. From this on, set up how to study the problem management to use of freshwater in the Areia Branca region (Aracaju Expansion Zone), where part of the population makes use of wells as a source of water supply for consumption. Thus, the present study aimed to analyze the from the site characterization, a perception and sustainable practices as realized for the population and if there is destination given the domestic sewage or toilets. Such research was based a qualitative and quantitative methodological approach in order to understand and analyze the related facts on environmental sanitation, more precisely the types of water use, prospecting quality materials to inform a real importance to an overview questioning. To this end, they were performed: bibliographical and documentary survey; questionnaires to the community concerned and the relevant public bodies; observations "in loco"; experimental research to prove the level of quality (potable) water; mapping of collection points; tab and management of data; and analysis and interpretation of information. With the diagnosis and the analysis performed, it can be seen that the village lacks basic sanitation and environmental infrastructure, because the quality of the water used by the population, in general, does not meet the potability standards required by Brazilian law; and also the financial resources allocated to this region are insufficient for the maintenance of other issues related to public health, as the case of the lack of land use planning, urban drainage and sewerage system. Through the data obtained may also conclude that the perception of the population regarding the use of water, for the sustainable practices, falls short of emotional relationships between man and the environment, it is imperative to implement environmental education practices subsidize such relationship and therefore the sustained use of water. Thus, this research provided reveal the static scenario in which it is the region in terms of environmental development, lacking energetic solutions to minimize the problems faced by the resident population and therefore sensitize them on environmental issues. In contrast, it is expected that this study will provide more information for the academic community and tools for the management of water resources through public policies aimed at the population's well-being as well as the preservation of natural resources, advocating the importance of water quality for improving the quality of life and the maintenance of human health. / Uma das maiores preocupações dos tempos atuais diz respeito às questões ambientais e principalmente em temas relacionados à gestão dos usos das águas desde o seu consumo, em níveis de qualidade e quantidade necessários à população, até o despejo de rejeitos oriundos de seu uso. Diante disso, definiu-se como problema de estudo o gerenciamento do uso das águas doces na região de Areia Branca (Zona de Expansão de Aracaju), onde parte da população faz uso de poços como fonte de suprimento de água para o consumo. Para tanto, o presente estudo objetivou analisar, a partir da caracterização local, a percepção e as práticas sustentáveis realizadas pela população no uso da água e no destino dado aos esgotos domésticos/sanitários. A pesquisa fundamentou-se numa abordagem metodológica qualitativa e quantitativa com o intuito de conhecer e analisar os fatos relacionados ao saneamento ambiental, mais precisamente os tipos de uso da água, prospectando materiais de qualidade para informar a real importância do questionamento apanhado. Para tal, foram realizados: levantamento bibliográfico e documental; questionários aplicados à comunidade em questão e aos órgãos públicos correspondentes; observações “in loco”; pesquisa experimental para comprovar o nível de qualidade (potabilidade) da água; mapeamento dos pontos de coleta; tabulação e ordenamento dos dados; e análise e interpretação das informações. Com o diagnóstico e as análises realizadas, pode-se verificar que o povoado carece de infraestrutura de saneamento básico e ambiental, pois a qualidade da água utilizada pela população, de uma maneira geral, não atende aos padrões de potabilidade exigidos pela legislação brasileira; e também os recursos financeiros destinados a esta região são insuficientes para a manutenção de outras questões vinculadas à saúde pública, como o caso da falta de ordenamento territorial, da drenagem urbana e do sistema de esgotamento sanitário. Por meio dos dados obtidos pode-se concluir também que a percepção da população a respeito do uso da água, quanto às práticas sustentáveis, está aquém das relações afetivas entre o homem e o meio ambiente, sendo imprescindível a implementação de práticas de educação ambiental para subsidiar tal relação e, por conseguinte, o uso sustentado da água. Dessa forma, essa pesquisa proporcionou revelar o cenário estático em que se encontra a região, em termos de desenvolvimento socioambiental, carecendo de soluções enérgicas para minimizar os problemas enfrentados pela população residente e, por conseguinte, sensibilizá-la quanto às questões ambientais. Em contrapartida, espera-se que este estudo possa oferecer mais informações para a comunidade acadêmica e ferramentas para o gerenciamento dos recursos hídricos através de políticas públicas que visem o bem-estar da população, bem como a preservação do recurso natural, preconizando a importância da qualidade da água para a melhoria da qualidade de vida e da manutenção da saúde humana.
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Cenários de reúso de água pluvial e controle da drenagem visando a recuperação ambiental da micro-bacia do alto Tijuco Preto, São Carlos-SP / Scenarios of rain water reuse and control of urban drainage to environmental recovering the Alto Tijuco Preto micro basin, São Carlos-SP, Brazil

Alfredo Akira Ohnuma Júnior 03 February 2005 (has links)
A pesquisa objetiva a composição de cenários de planejamento para o Plano Diretor utilizando-se de medidas de recuperação ambiental através de uma bacia selecionada. São avaliadas simulações hidrológicas através: a) da implantação de: medidas de reúso de águas pluviais com microreservatórios instalados no lote, b) da arborização urbana, c) do reservatório de detenção, d) do coeficiente de permeabilidade, e outras medidas para micro e macro-drenagem. A metodologia utiliza uma base regional para espacializar através de bacias embutidas (MENDIONDO E TUCCI, 1997) a classificação de uso e ocupação do solo para os anos: 1962, 1972 e 1998. Os resultados oferecem diretrizes para novos empreendimentos, loteamentos urbanos e políticas públicas. A situação de passivo ambiental da bacia justifica o estudo em micro-bacias urbanas embutidas. As simulações envolvem cenários retrospectivos de 40 anos, atual e prospectivos de 15 anos com e sem Plano Diretor. Os critérios adotados resultam para o planejamento ambiental melhorias na carga de poluição hídrica e prevê a recuperação de suas funções hidrológicas e ambientais. Inclui-se uma análise de incertezas a partir dos diferentes estados de condições de umidade antecedente que afetam o valor de CN. A partir destes resultados, recomenda-se avaliar novos cenários de planejamento, instrumentação de monitoramento para bacias sem dados que visem o estudo aplicado do aproveitamento de águas pluviais no lote associado às incertezas das previsões hidrológicas dessas bacias sem dados, conforme o programa PUB - Predictions in Ungauged Basins (SIVAPALAN et al, 2003) / The research aims to compose planning scenarios for Master Plan using measures of environmental recovering to control of urban drainage at the scale of an ungauged basin selected. Hydrologic simulations are assessed by the implementation of several measures as: a) indirect impacts of rain water use system in the urban lot, b) urban arborization, c) detention reservoir, d) permeability coefficient and complementary measures at micro and macro drainage. The methodology uses regionally-based nested basins (MENDIONDO e TUCCI, 1997) with a classification of land-use in years: 1962, 1972 and 1998. Results will offer directive to new urban achievements and water policies. Environmental passive situations (diagnosis) at the basin scale justify experimental studies in nested urban micro-basins. The simulations involve retrospective scenarios through 40 years, present state (1998) and prospective scenarios of 15 years with and without master plan. Criteria adopted result in best management practices (BMP’s) in water pollution and foresee recovery of hydrologic environmental functions. Analysis of uncertainties of hydrologic estimations to different antecedent moisture conditions through the CN parameter is also presented and discussed. From these results it is recommended to assess new planning scenarios that aim experimental study, thereby looking forward to proposing new concepts of rain water use, i.e. by using micro reservoir at domiciliary lot. These scenarios are to be depicted into the hydrologic uncertainties at basins without data especially addressing the PUB program - Predictions in Ungauged Basins (SIVAPALAN et al, 2003)

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