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Aplicação de vinhaça via gotejamento subsuperficial e seus efeitos nos perfis de distribuição iônica e atributos físicos e químicos de um Nitossolo / The effect of vinasse application by subsurface drip irrigation on ion distribution profile and physical and chemical attributes in nitosol soilJoão Alberto Lelis Neto 16 October 2012 (has links)
O aumento da produção de cana-de-açúcar no Brasil é de grande relevância para o cenário agroindustrial atual do país. Entretanto, acarreta a um aumento na geração de subprodutos do setor de usinas sucro-alcooleira. Dentre esses subprodutos destaca-se a vinhaça, pois possui uma série de nutrientes em sua composição. Diante do grande volume de vinhaça obtido e de sua aplicação em áreas de cana-de-açúcar, sugerem-se pesquisas em relação à sua aplicação e ao deslocamento de seus principais componentes químicos no perfil do solo, com a intenção de prever e evitar a contaminação de águas subterrâneas. Portanto, durante o primeiro ciclo de cultivo da cana-de-açúcar, os objetivos dessa pesquisa foram: avaliar a distribuição de alguns componentes químicos da vinhaça (nitrato, potássio, cálcio, enxofre e sódio), avaliar a variação de alguns atributos químicos do solo (pH e condutividade elétrica), verificar a ocorrência de variações em algumas propriedades físico-químicas de um Nitossolo (granulometria, condutividade hidráulica e umidade do solo na capacidade de campo), bem como, avaliar o entupimento de gotejadores e a produtividade da cana-de-açucar, diante da aplicação de vinhaça, via gotejamento subsuperficial. A pesquisa foi conduzida na área experimental do Departamento de Engenharia de Biossistemas da ESALQ/USP, diante de um delineamento estatístico inteiramente casualizado com 6 tratamentos e 4 repetições. Os tratamentos implantados foram: T1: Sem irrigação com adubação convencional, T2: Fertirrigada sem vinhaça, T3: Fertirrigada com ½ dose Cetesb (176 m³ ha-1), T4: Fertirrigada com dose Cetesb (352 m³ ha-1), T5: Fertirrigada com 2x dose Cetesb (704 m³ ha-1) e T6: Fertirrigada com 3x dose Cetesb (1056 m³ ha-1). A aplicação de vinhaça foi feita aos tratamentos em um intervalo de tempo quinzenal. As avaliações foram feitas no início e ao final do ciclo da cultura nas camadas de 0,00-0,20 m; 0,20-0,40 m; 0,40-0,60 m e 0,60-0,80 m. Diante dos resultados obtidos pôde-se concluir que a distribuição dos íons está diretamente relacionada com o volume de aplicação da vinhaça e de uma maneira geral houve um aumento dos valores de pH e CE no solo, diante do aumento do volume aplicado, mas evidenciou-se a necessidade de um maior intervalo de tempo para a percepção de suas diferenças. As características físicas do solo não apresentaram variações significativas diante da aplicação de vinhaça, mesmo com altos valores de concentração, durante o primeiro ano de avaliação, porém, sugerese também um maior intervalo de tempo de aplicação e avaliação. O gotejador independente do tratamento não apresentou nenhum tipo de entupimento diante da aplicação de vinhaça e notou-se um aumento da produtividade de cana-de-açucar diante da aplicação de vinhaça, via gotejamento subsuperficial. / The increase in sugarcane production in Brazil shows a great relevance to the current agribusiness scenario of the country. However, it may also result in an increase of the by-product generation from sugar mills. Among these by-products, the vinasse stands out because of its diverse nutrient composition and its use in the sugarcane production as a fertilizer. Given the large volume of vinasse produced and their application in sugarcane fields, there is a need to study fate and transport of different chemical constituents of vinasse through the soil profile to prevent groundwater contamination. The objectives of this study are to evaluate the distribution of important chemical components of vinasse (nitrate, potassium, calcium, sulfur and sodium), to evaluate the variation of soil chemical properties (pH and electric cconductivity (EC)), to verify the occurrence of physico-chemical property (grain size, hydraulic conductivity and soil moisture at field capacity) variation in Nitosol soil, as well to evaluate the clogging in drip irrigation system and sugarcane yield under vinasse application by subsurface drip irrigation during first sugarcane cycle. The research was carried out at the experimental site of the Department of Biosystems Engineering (ESALQ/USP), in completely randomized experimental design with six treatments and four replications. The treatments deployed were: T1: no irrigation with conventional fertilization, T2: fertigated without vinasse, T3: fertigated with ½ Cetesb dose (176 m³ ha-1), T4: fertigated Cetesb dose (352 m³ ha- 1), T5: fertigated with 2x Cetesb dose (704 m³ ha-1), and T6: fertigated with 3x dose Cetesb (1056 m³ ha-1). The vinasse treatment were applied on a biweekly basis. Chemical transport and soil sample analysis were done at the beginning and the end of the cycle in four layers, each with thickness of 0.2 m. Based on these results, it is concluded that the ions distribution is directly related to the application volume of vinasse and in general, there was an increase in pH and EC in the soil, in relation to the increase in the applied volume. Since the duration of this study was one year, the experiments with larger time interval might show a distinct relationship between variation in soil chemical properties and the volume of vinasse applied. However, the analysis did not show significant variation in soil physical characteristics before and after the application of vinasse, even with high concentration values during the first year of the study. This indicates a need for a longer time of application and evaluation. The drip irrigation system used for vinasse application did not show any kind of clogging during the study period and the sugarcane yield increased with vinasse application by subsurface drip irrigation.
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Estudo da distribuição da solução no solo aplicado por gotejamento enterrado e superficial / Soil solution distribution study applied by subsurface and surface drip irrigationAllan Cunha Barros 16 January 2008 (has links)
Em função do número reduzido de estudos sobre o movimento da água e de íons no bulbo molhado, foi realizado este trabalho com o objetivo de avaliar a distribuição de água e concentração de nutrientes no bulbo formado pelo sistema de gotejamento enterrado em comparação ao superficial. O ensaio foi conduzido na área experimental do Departamento de Engenharia Rural da Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ/USP, localizada no município de Piracicaba, SP. Para a avaliação foram abertas trincheiras e instaladas sondas de TDR, para o monitoramento da distribuição da solução, dispostas a 0,5; 0,15; 0,25; 0,35 e 0,45 m - profundidade, e a 0,5; 0,15; 0,25; 0,35 m - comprimento, totalizando 17 sondas em malha por trincheira. A solução de KNO3 foi aplicada a partir de gotejadores com diferentes vazões (2 e 4 L/h), sendo aplicado o volume de 1 L em intervalos de 1 hora, totalizando 10 L de solução por repetição, Conjuntamente ao monitoramento da distribuição da solução no solo, medições da área superficial molhada e do disco saturado foram feitas com régua milimetrada, além disso, foi estabelecido um volume de controle onde foram avaliadas a uniformidade de aplicação de água e KNO3. Desta forma, foi possível verificar que: em relação aos sistemas superficiais, os sistemas enterrados apresentaram menor área superficial molhada e atingiram uma maior largura e profundidade; a umidade inicial do solo influencia a formação do bulbo molhado e o movimento do KNO3 no solo; a uniformidade de sais distribuídos no volume de controle é afetada negativamente pelo aumento do volume aplicado e as maiores concentrações de água e concentração de KNO3 foram obtidas próximas ao ponto de emissão. / In function of the reduced number of studies on the water and ions movement in the wet soil volume, this work was conducted with the goal of evaluating the distribution of water and nutrient concentration in the wetted soil volume formed by subsurface drip irrigation (SDI) in comparison to surface system. The rehearsal was concducted in the experimental area of the Rural Engineering Department - ESALQ/USP, located in Piracicaba, SP. Trenches were opened and installed probes of TDR for studying to solution distribution, to facilitate the study a mesh of probes was disposed to 0,5; 0,15; 0,25; 0,35 and 0,45 m - depth, and to 0,5; 0,15; 0,25; 0,35 m - length, with the total of 17 probes. The solution of KNO3 was applied starting from emitters with different flows (2 and 4 L/h), it was applied the volume of 1 L within intervals of 1 hour, with the total of 10 L of solution for repetition. All together to study the solution distribution in the soil, the wet superficial area measurements and of the saturated disc they were done by the ruler, besides, it was established a control volume where the uniformity application of water and KNO3 was analysed. This way, it was possible to verify that: in relation to the superface systems, the SDI presented smaller wet superficial area and they reached a larger width and depth; the initial soil water content influences the formation of the wetted soil volume and the KNO3 movement in the soil; the salt uniformity, distributed in the control volume, is affected negatively by the applied volume increased, and the largest concentrations of water and KNO3 were obtained close to the emission point.
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The fate of microbial contaminants in the subsurface with a South African case studyRajkumar, Yasmin January 2009 (has links)
Magister Scientiae - MSc / The time bound agenda of the Millennium Development Goals (MDG's) aims at reducing poverty, extending gender equality and advancing opportunities for health and education by addressing current and future water resource and sanitation needs. In many rural areas of South Africa, the cost implication of routing surface water supplies and providing water borne sewerage may far exceed the budgets of local water service authorities. This has resulted in a major thrust in service provision via localised sources, mainly boreholes and springs as well as on site sanitation options. Whilst the National Water Act (Act 36 of 1998) mandates the South African government to provide potable water to all citizens in an equitable manner, this needs to be balanced against the preservation of the country’s water resources both quantitatively and qualitatively to ensure sustainability. It is imperative that this fine balance between protection and effecting societal demands and economic development through large-scale water provision be maintained, as successful strategising will be resultant of integrated social, economic and environmental issues especially in economically developing countries. In order to fulfil the mandate of the NWA, policies and strategies for effective protection and use of groundwater resources have been drawn up and are in the process of being drawn up by the national Department of Water Affairs and Forestry (DWAF). The major scope of research in this thesis stems from feasibility studies commissioned by the DWAF for the implementation of a groundwater protection zoning policy for the management and protection of groundwater resource quality. The research work focuses on specifically the microbiological zone of protection and attempts to determine the fate of various pathogens that emanate from on site sanitation facilities as they move through the subsurface. The research was predominantly proposed as a desktop collation and analysis of existing published data however; it was later decided to include a local case study site. / South Africa
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Analyse des processus d'écoulement lors de crues à cinétique rapide sur l'arc méditerranéen / Flash food modelling for a better understanding of hydrological processes in the MediterraneanDouinot, Audrey 12 December 2016 (has links)
L'objectif de la thèse est d'améliorer la compréhension des processus hydrologiques lors des événements de crues éclair. Se basant sur un modèle existant (MARINE), l'étude se concentre sur les processus internes au sol. Une étape préliminaire permet, à partir de l'analyse des données, de confirmer l'activité du socle rocheux durant les crues éclair. Une analyse structurelle de MARINE est réalisée, afin de connaître la sensibilité des flux de subsurface aux choix structurels. Une nouvelle modélisation, plus robuste et intégrant explicitement une représentation des roches altérées, est mise en place. Supposant des chemins préférentiels à l'interface sol/roche, le modèle donne une bonne reproduction des bassins sédimentaires. Sur les bassins granitiques, il sous-estime les récessions et, en conséquence, les éventuels seconds pics de crue, montrant la nécessité de représenter des flux significatifs sur ces bassins, y compris dans la zone altérée. / The purpose of this thesis is to improve the knowledge of hydrological processes during flash flood events using rainfall-runoff modelling. The project focuses on hydrological processes occurring into soil and subsoil horizons. A preliminary data analysis corroborates the activity of the weathered bedrock during flash floods. The hydrological response, simulated by the MARINE model, is then investigated to detect the sensitivity of subsurface flow processes to model assumptions. It leads to several modifications of the model structure in order to make it more robust. Moreover a two-layered soil column is implemented to explicitly integrate the activity of the weathered bedrock into the model. Assuming preferential path flows at the soil-bedrock interface, the model performs well on sedimentary watersheds, but underestimate recession curves and second flood peaks on granitic ones, showing the need to simulate as well significantcontribution from the weathered bedrock.
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Maîtrise de l’azote en système irrigué : application au contexte méditerranéen / Nitrogen control in unsaturated agricultural soils under irrigated systems : application to Mediteranean contextBarakat, Mohammad 12 May 2017 (has links)
La maîtrise du transfert de nitrates sous les systèmes irrigués est un objectif primordial dans l’agriculture moderne. Celle-ci exige la recherche, surtout en plein champ, de conduire une stratégie optimale de fertigation. Dans ce but, un protocole expérimental sur une parcelle de 2 ha a été mis en oeuvre pour analyser le devenir de l’’azote sous différents scénarios d’irrigation et de fertilisation d’une culture de maïs. Dans l’articulation de ce travail, et pour pouvoir étudier la dynamique de l’azote en systèmes irrigués, nous avons tout d’abord réussi à définir et clarifier la relation ambigüe entre la méthode d’irrigation (irrigation gravitaire, par aspersion ASP, en goutte à goutte de surface GGS ou enterré GGE) et les différentes transformations de l’azote (Fixation, Minéralisation, Immobilisation, Nitrification, Dénitrification et Volatilisation). Cette relation, peu claire et non traitée dans d’autres études similaires, a été étudiée en mettant l’accent sur l’effet de certains facteurs, comme par exemple, l’humidité de sol et sa température, sur l’activité microbienne et donc sur les différentes transformations de l’azote (comme la minéralisation) et ce en mettant en avant la relation directe ou indirecte avec les méthodes d’irrigation. Une différence significative a été observée pour la minéralisation in situ entre les traitements sans aucun apport d’engrais menés sous les deux méthodes d’irrigation GGE et ASP. Une méthode manuelle d’analyse a été ensuite mise au point et validée pour déterminer la concentration en azote dans les échantillons de sol prélevés dans le cadre de ce travail. Cette méthode peu onéreuse pourrait être profitable aux agriculteurs. Les données issues de l’ensemble des traitements ont été utilisées pour modéliser les flux hydriques et azotés à l’aide de modèle HYDRUS-2D pour les systèmes par aspersion et en goutte à goutte enterré. L’analyse de sensibilité aux paramètres liés au transfert de nitrates du modèle de transfert a permis d’estimer la dynamique azotée pour d’autres contextes hydro-pédo-climatiques plus complexes. En conclusion, la présente thèse a permis d’améliorer la connaissance du fonctionnement de la fertigation en irrigation goutte à goutte enterré par comparaison avec l’aspersion, en milieu méditerranéen, en vue d’une diminution des entrants agrochimiques dans un contexte d’économie de la ressource en eau. / The main goal in modern agriculture is the control of nitrogen fluxes in agricultural soils under the irrigation techniques. This objective requires a lot of research, especially in the field, to escort an optimal strategy of fertigation. For this purpose, an experimental protocol has been applied to follow the soil nitrogen fate for various irrigation and fertilization scenarios, during two intensive field campaigns in maize plots. In the articulation of our work, and to be able to examine the nitrogen dynamics in unsaturated agricultural soils under irrigated systems, we succeeded firstly to determine and clarify the ambiguous relation between the irrigation techniques (flood irrigation, sprinkler irrigation, surface and subsurface drip irrigation) and the different nitrogen transformations (Fixation, Mineralization, Immobilization, Nitrification, Denitrification and Volatilization) in agricultural contexts. This relationship, which is unclear and untreated in other similar studies, has been reviewed by studying the impact of certain factors, such as soil moisture and soil temperature under different irrigation techniques, on microbial soil activity and therefore on the nitrogen transformations (such as mineralization). A significant difference of mineralization was observed in maize plots with no fertilizer application treatment between sprinkler irrigation and subsurface drip irrigation. The experimental data collected have been used to analyze the water and nitrogen fluxes for various initial conditions and fertilisation strategies under sprinkler and subsurface drip irrigation by using the HYDRUS-2D model. Analyzing the sensitivity of nitrogen fluxes parameters using HYDRUS-2D allowed to estimate the nitrogen dynamics under more complex agro-pedoclimatic contexts. In conclusion, the present study allowed to improve the fertilization knowledge under both the sprinkler and subsurface drip irrigation in a Mediterranean environment.
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Patterns of water table dynamics and runoff generation in a watershed with preferential flow networksAnderson, Axel Edward 05 1900 (has links)
Our understanding of subsurface flow depends on assumptions of how event characteristics and spatial scale affect the relationships between subsurface water velocity, discharge, water table dynamics, and runoff response. In this thesis, three chapters explore some of these patterns for a hillslope and small watershed in coastal British Columbia. In the first chapter, tracers were applied under natural and steady state conditions to determine the relationship between lateral tracer velocities and various hillslope and event characteristics; such as hillslope subsurface flow, rainfall intensity, water table level, hillslope length, and antecedent condition. The results showed that preferential flow made up a large percentage of the subsurface flow from the gauged hillslope. Flow velocities as measured by tracers were affected by slope length and boundary conditions. The flow velocity was most closely related to the rainfall intensity, and changes in flow velocity were large compared to the changes in the water table. In the second chapter, the preferential flow features that transmitted water during steady state were investigated by staining the soil with a food dye solution and excavating the soil. These data were used to explore the link between the topographical factors (slope and contributing area), the network of preferential features and soil properties. The contributing area appeared to be an indicator of the size of the preferential features and their connectivity. In the final manuscript chapter, water table level and stream discharge measurements were used to determine if areas within a watershed with runoff dominated by preferential flow could be grouped based on the observable physical information such as slope, contributing area, distance to stream, and vegetation. Preferential flow made the water table responses dynamic and thus, distinct zones could not be identified. Models of the water table – runoff were not able to predict the water table response for other sites with similar physical characteristics. Even though there was high variability in the results, the patterns and relationships revealed in this thesis conform to existing conceptual models of hillslope subsurface preferential flow. These patterns and relationships may be useful in developing or validating numerical models. / Forestry, Faculty of / Graduate
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Characterization of Bacterial Community Structure in Deep Subsurface Sedimentary Core Samples from Michigan Basin, OntarioIlin, Dimitri January 2012 (has links)
Deep subsurface rock samples from Upper Ordovician strata in the Michigan Basin were analyzed for the presence of microbial communities. High concentrations of biogenic methane were observed in the Upper and Middle Ordovician formations. Total porosity values for the shale, shale hard bed and limestone samples were 7.4%, 2.5% and 1.9%, respectively. Hydrocarbon presence ranged from petroliferous shale, to bituminous layering in shale hard beds, to hydrocarbon odour in limestone. Organic carbon content ranged from 0.5 to 2.5%, highest amount being present in the shale. Environmental DNA was extracted from core samples and PCR amplified using 16S rDNA bacterial primers. PCR performed with archaeal 16S rDNA and methanogen-specific (mcrA) primers did not yield DNA amplification. Gene analysis indicated that bacterial sequences similar to Proteobacteria, Cyanobacteria, Firmicutes, and Actinobacteria were present. Most sequences were not related to known cultivated species. Proteobacteria was the most dominant phyla at all depths and included heterotrophic, lithotrophic, acidophilic, radiotolerant, and sulphate-reducing species of bacteria. This study concludes that the observed biogenic methane is a product of ancient methanogenesis.
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Studie rekonstrukce železniční stanice Kyjov / Upgrading of Kyjov Railway StationPrikner, Pavel January 2019 (has links)
The master´s thesis deals with the reconstruction design of Kyjov railway station. The solution is aimed at meeting the traffic requirements, modifying the layout of the platforms and access routes for the safe movement of people with reduced mobility and orientation. The proposal deals with rail crossing in accordance with current legislations. In this thesis is proposed renewal of drainage.
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Čištění odpadní vody pro skupinu domů v k.ú. Samopše / Wastewater Treatment for a Group of Houses in the Cadastral Area of SamopšePoloprutská, Tereza January 2019 (has links)
Subject of this thesis is ecologic wastewater treatment with little organic load. Treated wastewater for infiltration must contain low values of nitrogen. This thesis is about to design two-stage subsurface vertical flow constructed wetland.
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Technologie pro zvýšení propustnosti vod v kořenových ČOV / Technology to increase hydraulic conductivity of constructed wetlandsPobořil, Jan January 2014 (has links)
Constructed wetlands are one of alternative solution wastewater treatment. Compared to conventional wastewater plants have many advantages. For example it´s technology saving construction, low operating costs, cleavability diluted wastewater and little or no need for electrical power. There are many publications dealing with Natural Ways wastewater treatment or even constructed wetlands. I decided to look for a thesis on one of the key processes – clogging bed media. The thesis is focused on ways to prevent clogging of bed media, mitigate the consequences and technology to increase hydraulic conductivity of constructed wetlands. The main test method is improving drainage parameters using pulsed filling and emptying of the bed media. This method is a very effective way to achieve quality requirements for effluent water from the treatment plant. Another test method is based on the injection of air into the media bed and sludge extraction using a specially modified industrial vacuum cleaner or pump.
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