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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.
11

Seasonal adaptations in the energetics and biomechanics of locomotion in the Svalbard rock ptarmigan (Lagopus muta hyperborea)

Lees, John January 2013 (has links)
One of the most striking things about many animals is that they can be defined by the ways in which they move. Moving costs metabolic energy and is a significant contributor to the daily energy balance of organisms and therefore fitness. Balancing energy needs is critically important to species inhabiting areas of limited resources. The metabolic cost of locomotion is influenced by physiological, morphological and behavioural factors that vary across species. The influence of these factors within species is less well understood. The objective of my PhD is to elucidate the potential for variation in locomotor performance, in particular the energy consumed and the biomechanics of locomotion within a species, in response to differences in season, sex, age and the nature of the terrain. The Svalbard ptarmigan (Lagopus muta hyperborea) is the only year-round avian resident of the Arctic archipelago of Svalbard. Svalbard is characterized by extreme photoperiodic and climatic conditions, with 24 hours of daylight in summer and continuous darkness in winter, when ice makes food unpredictable. As a result, ptarmigan annually gain significant fat stores, as much as doubling their body mass in winter. The consequences of such large gains in mass upon the metabolic cost and biomechanics of terrestrial locomotion are yet to be quantified. The Svalbard ptarmigan represents a unique opportunity to gain insight into avian adaptations.Using respirometry, I present evidence that winter birds are able to carry their fat stores at no metabolic cost. Using kinematic and force plate data, I show that acquiring fat results in reduced locomotor performance in terms of speed and take-off ability. As well as exhibiting phenotypic variation, male and female Svalbard ptarmigan are behaviourally very different. I present evidence that these behavioural differences are reflected in the metabolic cost of locomotion. In particular, males are both more efficient and faster than female birds during both summer and winter. I suggest that this results from sexual selection upon male locomotor performance. Furthermore, I present data demonstrating that sub-adult males experiencing their first winter possess the same metabolic and speed capabilities of adults. These data may indicate that selection for improved male locomotor performance may act upon sub-adult birds. Regardless of season, age or sex, Svalbard ptarmigan must locomote on a predominantly sloping terrain. The influence of inclines upon the metabolic cost of locomotion in birds is poorly understood. I provide evidence that at the same degree of incline, the cost of lifting 1 kg by 1 vertical metre is similar regardless of season and is therefore dictated by increased positive work. However, this cost varies according to the degree of incline and may be influenced by gait.The principal findings of the 5 first author papers presented are that behavioural, physiological and morphological variation within a species can have significant impacts upon the metabolic cost of locomotion and other aspects of locomotor performance. The potential for intraspecific differences should therefore be taken into account in future research regarding the patterns of energy expenditure in animals.
12

Analysis of Oxygen Transfer at an Activated Sludge Plant: A Procedure for Monitoring Aeration Efficiency

Luke, Benjamin Clyde 11 August 2012 (has links)
In this investigation, two separate methods for determining oxygen transfer rates were applied to the oxidation ditches of an activated sludge plant. Steady state oxygen uptake rate testing and an oxygen mass balance technique were used to propose an in-process procedure for monitoring aeration efficiency using available resources. Although some overall averages offered promise, the testing results revealed that the mass balance analysis yielded results that do not accurately represent the oxygen transfer capabilities within the individual reactors due to shared variables that control the oxygen transfer rate. The steady state method provided more favorable results. Overall averages of daily oxygen transfer rates determined using the steady state method displayed a ratio of oxygen transfer rate between the reactors that corresponds to the expected ratio of 5/6 derived from the linear feet of aerator rotor present in each reactor.
13

Physiological Response of the Giant Acorn Barnacle, Balanus nubilus, to Air Exposure

Resner, Emily Jane 01 November 2018 (has links) (PDF)
The giant acorn barnacle, Balanus nubilus, is a resident of the subtidal and low intertidal rocky shoreline on the Pacific Coast of North America (Alaska to Baja California). B. nubilusis notable for having the largest muscle fibers in the animal kingdom; fiber diameters that can exceed 3mm in adults! At such extreme sizes these muscle cells may be at risk for insufficient oxygen delivery to mitochondria owing to low SA:V ratios and long intracellular diffusion distances. Oxygen limitation to these muscles may be further exacerbated during low tide air exposure (emersion) or environmental hypoxia events, which are increasing in frequency and duration along the world’s coastlines. We are interested in characterizing the internal oxygen conditions of B. nubilus during air emersion and anoxia so that we can ultimately investigate the physiologic mechanisms by which B. nubilus maintains function in their giant muscle fibers during environmental oxygen limitation. To this end, we examined the effects of air emersion and anoxia on 1) hemolymph gas, pH and ion levels, 2) oxygen consumption rates (MO2; emersion only), and 3) respiratory behaviors (e.g., cirri beating). In the first experiment, we measured hemolymph pO2, pCO2, pH and ion ([Na+], [Cl-], [K+], [Ca2+]) concentrations at 0, 3, 6 and 9h of exposure to air emersion, anoxic immersion and normoxic immersion (control). Next, we compared the average MO2 of barnacles held in water and air for 6h at three common temperatures (10, 15, or 20°C) using intermittent (aquatic) and closed-system (air) respirometry. Lastly, we investigated the respiratory behaviors (% time operculum open, %time testing, % time pumping, % time cirri beating, cirri beat frequency, opercular pulse frequency) of B. nubilusduring acute (6h) exposure to air emersion, anoxic immersion and normoxic immersion (control). Our data revealed that hemolymph pO­2 was significantly decreased in the anoxic barnacles by 3h and remained significantly depressed relative to the normoxic control for 9h. The air-exposed barnacles, however, maintained hemolymph oxygen levels that were intermediate to the control and anoxia barnacles for the entire experiment, achieving levels that were significantly lower than normoxic barnacles only by 9h. We also found that oxygen consumption rates for B. nubilus held at ecologically realistic temperatures were similar in air and water. From these data we conclude that B. nubilus is relatively adept at taking up oxygen from the environment while out of the water, which is common for certain barnacle species, and that air emersion represents a relatively mild environmental stress for this species (at least from a gas-exchange perspective). Efficient aerial gas-exchange by the giant acorn barnacle is likely facilitated by seawater pools stored in the mantle cavity, which can directly take up oxygen from the air and make it accessible to soft tissues and gill-like structures on the inside of the shell. This strategy, however, would require complementary behaviors aimed at oxygenating the mantle cavity fluid (e.g, aperture opening, cirri extensions to facilitate mixing), and this is exactly what we see. In our behavior experiment we found that air-exposed barnacles (and, more surprisingly, anoxic barnacles) spent significantly more time with their cirri extended than our control animals, who engaged more in an aperture pumping behavior with their cirri retracted. These behavioral preferences existed even though there were no significant differences in the total time spent with their aperture open (regardless of the behavior occurring while open) between any of the treatments. There were also interesting findings in the ion data. While there were no significant treatment effects on [Na+], [Cl-], or [Ca2+], we did observe significantly higher [K+] by 6h in both the emersion and anoxic groups relative to the normoxic group. We predict that this change in [K+] is likely attributable to its role in acid-base buffering. There was a strong correlation between pCO2 levels and pH across all treatments; however, decreases in pO2 levels in the hemolymph, which corresponded with increases in pCO2 levels, had only minimal effects on the hemolymph pH, indicating a well-buffered system. In conclusion, we found that air exposure does not inhibit aerobic metabolism in B. nubilus, owing largely to efficient aerial oxygen uptake and perhaps also effective acid base-buffering. We therefore predict that muscle function would be preserved during periods of low-tide emersion. Anoxia, on the other hand led to a significant decline in hemolymph oxygen content, which suggests that environmental hypoxia is likely to diminish functionality of their giant muscle fibers. In a parallel study, we intend to investigate the plastic response of B. nubilus muscle fibers to the same conditions (air emersion and anoxic immersion).
14

THE STRESS OF BEING ON TOP: HIGH-ALTITUDE ADAPTATIONS AND PHENOTYPIC PLASTICITY OF MITOCHONDRIA IN DEER MICE

Mahalingam, Sajeni January 2017 (has links)
Hypoxia is a major stressor at high altitudes that limits tissue oxygen availability. High altitude environments are also extremely cold which increases thermogenic demand. Small mammals living at high altitude face the competing energetic challenge of maintaining thermogenesis in a hypoxic environment that can impair aerobic ATP supply. It has been suggested that hypoxia-induced impairments in ATP synthesis capacity and cold-induced increases in thermogenic demand could be counteracted by an increase in tissue oxidative capacity and/or fuel selection. As the organelle that consumes oxygen to produce ATP, changes in mitochondrial physiology can help offset physiological impairments at high altitudes. We explored this hypothesis in North American deer mice (Peromyscus maniculatus), from populations native to high and low altitude. We compared mitochondrial volume densities, intracellular distribution, respiratory capacities, enzyme activities of the mitochondrial complexes, capillarity, and fibre-type distribution in skeletal and cardiac muscles. To examine potential changes to mitochondrial physiology at high altitudes deer mice (P. maniculatus) were acclimated to: warm (25°C) normoxia; warm hypoxia (simulated altitude of 4300m); cold (5°C) normoxia; and cold + hypoxia. In skeletal muscle, highlanders had higher mitochondrial volume densities than lowlanders, entirely due to an increased abundance of mitochondria in a subsarcolemmal location next to capillaries. Mitochondria from highland mice also had higher mitochondrial respiratory capacities and cytochrome c oxidase activity in control conditions, but these values converged after hypoxia acclimation. Cold acclimation restored pyruvate and fatty acid respiratory capacity to control levels in highland mice, which also showed an increase in mitochondrial uncoupling. Cold increased respiratory capacities in lowland mice. Acclimation to cold+hypoxia did not change mitochondrial physiology beyond cold alone and appeared to counteract the effects of hypoxia on highland mice. In cardiac muscle highland mice had higher respiratory capacities, but after hypoxia acclimation lowland mice significantly increased respiratory capacities. In response to hypoxia, highland mice increased the relative capacity to oxidize carbohydrates compared to fatty acids. Our results suggest that both highland ancestry and plasticity affect mitochondrial physiology, and likely contributes to performance at high altitudes. / Thesis / Doctor of Philosophy (PhD)
15

Interactive effects of wastewater effluent and hypoxia on the metabolic physiology and health of mummichog killifish (Fundulus heteroclitus)

Lau, Samantha Chi-Lok January 2020 (has links)
This thesis is organized in “sandwich” format, as recommended by my supervisory committee. It consists of three main chapters. Chapter one is a general introduction and outlines the background information leading to the objectives and hypotheses of my thesis research. Chapter two is a manuscript prepared for submission to a peer-reviewed scientific journal. Chapter three is an overview of the major findings of this thesis, their implications in fish physiology and ecotoxicology, including suggestions of future directions of research. Appendix A contains data from an additional series of experiments that were conducted during my thesis but are not included as a full data chapter. It will be prepared for publication after my defence. / Hypoxia often occurs in aquatic ecosystems that receive effluent from municipal wastewater treatment plants (WWTP). WWTP effluent contains contaminants that could disrupt the complex physiological pathways fish use to cope with hypoxia (e.g., pharmaceuticals, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons), but the effects of WWTP effluent on the physiological responses of fish to chronic hypoxia is poorly understood. We exposed mummichog killifish (Fundulus heteroclitus) to hypoxia (5 and 2 kPa O2) and/or WWTP effluent for 21 days in a full factorial design. We then measured hypoxia tolerance, whole-animal metabolism, gill morphology, haematology, and tissue metabolites. In clean water, killifish responded to chronic hypoxia with improvements in hypoxia tolerance – increases in time to loss of equilibrium at 0.5 kPa (tLOE) and decreases in critical O2 tension (Pcrit) – in association with increased gill surface area as a result of regression of the interlamellar cell mass (ILCM). Concurrent exposure to wastewater attenuated the increases in tLOE and gill remodeling in chronic hypoxia, and nearly depleted brain glycogen stores. Therefore, exposure to WWTP effluent can disrupt the physiological mechanisms fish use to cope with chronic hypoxia and impair hypoxia tolerance. My research suggests that the combination of stressors near WWTPs can have interactive effects on the physiology and health of fish. / Thesis / Master of Science (MSc) / Low oxygen conditions, known as ‘hypoxia’, frequently occur in aquatic ecosystems that receive municipal wastewater treatment plant (WWTP) effluent. WWTP effluent is a continuous and complex source of pollution, including contaminants that can disrupt fish physiology, affecting their ability to cope with stressors, like hypoxia. The effects of WWTP effluent on the responses of fish to chronic hypoxia are poorly understood. To address this research gap, I examined the effects of hypoxia and WWTP effluent on chronically exposed mummichog killifish. I provide evidence that combined exposure to hypoxia and wastewater affected hypoxia tolerance, gill structure, and depleted energy stores in the brain. My thesis demonstrates that WWTP effluent can disrupt mechanisms that fish use to cope with chronic hypoxia and impair hypoxia tolerance. These findings contribute to the existing body of work that documents the interactive effects of combined stressors in effluent-dominated ecosystems on the physiology and health of fish.
16

TREATMENT OF WASTEWATER GENERATED BY WOOD-BASED DRY INDUSTRIES: ADVANCED OXIDATION PROCESSES & ELECTROCOAGULATION

Hansson, Henrik January 2014 (has links)
Wood is a material with an enormous number of applications. For decades, the development of wastewater treatment technologies tailored for the wood sector has focused on those industries that have water as an integral part of the industrial production, such as paper and pulp. However, there is a large and potentially growing sector that has been neglected, which is formed by industries in which water is not part of their production line, as for example, the wood floor and furniture industries (named wood-based dry industries). These industries still produces relatively low volumes of highly polluted wastewaters, with COD up to 30,000 mg/L, due to cleaning/washing procedure (named cleaning wastewaters). These cleaning wastewaters are often sent to the municipal wastewater treatment plant after dilution with potable water. Once there, recalcitrant pollutants are diluted and discharged into recipient water bodies or trapped in the municipal wastewater sludge. Another type of contaminated water these “dry industries” often generate in high volumes, and which is usually discharged with no previous treatment, is storm-water containing contaminants that have leached from large wood storage areas. The overall aim of this thesis was to increase the level of knowledge and competence and to present on-site wastewater treatment options for wood-based dry industries using the wood floor industry as a case-study, with a focus on combined treatment methods and solutions applicable to both the cleaning wastewater and storm-water. Among the treatment technologies investigated, electrocoagulation was studied both as a standalone treatment and combined with sorption using activated carbon. The combined treatment achieved a COD reduction of approximately 70%. Some advanced oxidation processes (AOP) were also studied: a COD reduction of approximately 70% was achieved by photo-Fenton, but the most successful AOP was ozone combined with UV light, were a COD reduction around 90% was achieved, with additional improvement in the biodegradability of the treated effluent. Ozone also proved to be effective in degrading organic compounds (approximately 70% COD reduction) and enhanced the biodegradability of the storm-water runoff from wood storage areas. The results have shown that the application of ozone can be considered an option for treatment of cleaning wastewaters and possibly for storm-water biodegradation enhancement. / Trä är ett material med ett stort antal möjliga användningsområden. Inom träindustrin har utvecklingen av vattenbehandlingsmetoder varit inriktat på de branscher som har vatten som en del av produktionen, såsom papper- och massaindustrin. Men det finns en stor och potentiellt växande sektor inom träindustrin som har försummats, den utgörs av industrier som inte har vatten som en del av produktionen, t.ex. trägolv och trämöbel industrier. Trots detta så producerar dessa industrier fortfarande relativt kraftigt förorenade avloppsvatten med t.ex. COD-värden upp till 30000 mg/l men i relativt låga volymer. Dessa avloppsvatten uppkommer vid rengöring av maskiner och städning av lokaler, varefter de oftast efter utspädning med dricksvatten skickas till det kommunala reningsverket. Väl där späds det förorenade vattnet vidare ut med annat inkommande vatten men passerar dock till stor del obehandlat och släpps ut i mottagande vattendrag eller så fastnar föroreningarna i avloppsslamet. Dagvatten är en annan typ av förorenat vatten från dessa "torra industrier" som ofta genereras i stora volymer och innehåller föroreningar som lakats från de trämaterial som förvaras i de stora upplag som ofta förekommer vid denna typ av industrier. Det övergripande syftet med avhandlingen var att öka kunskapen och kompetensen för att kunna miljömässigt riktigt och ekonomiskt billigt behandla industriavloppsvatten lokalt på plats inom trävaruindustrin, genom att använda en trä-golvsindustri som fallstudie. Fokus lades på kombinerade behandlingsmetoder och lösningar som skulle kunna vara lämpliga både för industriavloppsvatten och dagvatten. Ett antal behandlingstekniker har undersökts; elektrokoagulering studerades både som en fristående behandling och i kombination med aktivt kol. Den kombinerade behandlingen gav en COD-reduktion på ungefär 70 %. Flera avancerade oxidationsprocesser (AOP) studerades också, och en COD-reduktion på cirka 70% uppnåddes med en kombination av UV-ljus och Fenton behandling. Den mest framgångsrika behandlingen var ozon i kombination med UV-ljus där en COD-reduktion runt 90 % uppnåddes varvid en avsevärd förbättring av den biologisk nedbrytbarhet på det behandlade avloppsvattenet erhölls. Ozon visade sig också vara effektivt för nedbrytning av organiska föreningar (ca 70% COD reduktion) och förbättrade den biologiska nedbrytbarheten av föroreningarna i dagvattnet från den studerade industrin. Resultaten har visat att ozon kan anses vara ett lämpligt alternativ för att behandla industriavloppsvatten inom trävarusektorn och möjligen för att öka den biologiska nedbrytbarheten av dagvattnet från dessa industrier / Integrated Approach for Handling of Industrial Wastewater and Stormwater / Triple Helix Collaboration on Industrial Water Conservation in Småland and the Islands
17

Efeito da aplicação de composto orgânico sobre a qualidade do solo cultivado com cana-de-açúcar (Saccharum spp.) / Effect of the application of organic compost on the soil quality cultivated with sugarcane (Saccharum spp.)

Apolari, João Paulo 26 February 2016 (has links)
A dinâmica ambiental possui capacidade limitada de reciclagem e a crescente utilização resíduos agroindustriais, especialmente na agricultura, pode levar a situações de poluição do solo e demais componentes ambientais. A manutenção da produtividade de ecossistemas agrícolas e naturais depende do processo de transformação da matéria orgânica e, por conseguinte, da biomassa microbiana do solo, e que é responsável pela decomposição e mineralização de resíduos no mesmo. A dinâmica natural dos microrganismos do solo, em constante mudança e adaptação, os torna um indicador sensível às mudanças resultantes de diferentes práticas de manejo agrícola. Sendo assim, conhecer essas alterações e suas interferências é fundamental para identificar estratégias adequadas de manejo, apontando técnicas de utilização adequadas. O objetivo deste trabalho foi avaliar a qualidade de um solo agrícola, cultivado com três variedades de cana-de-açúcar (Saccharum spp.), comparando a utilização de adubação mineral frente à utilização de fertilizante orgânico composto no período final de formação dos perfilhos (120 dias após o plantio). Foi implantado, em condições de campo, o cultivo de cana-de-açúcar (cana planta), utilizando as variedades RB 867515, RB 962869 e RB 855453, onde cada variedade foi cultivada de três formas distintas, sendo elas: plantio controle (CT) sem aplicação de insumos para adubação; plantio orgânico (OG) com aplicação de fertilizante orgânico; e plantio convencional (CV) com aplicação de adubação mineral, seguindo recomendações de adubação após análise química inicial do solo local. Cada parcela possuía 37 m2, com 5 sulcos de 5,0 m de comprimento e espaçamento de 1,5 m entrelinhas, sendo os três sulcos centrais formando a área útil. De acordo com a variedade e o tipo de adubação, foram formados nove tratamentos: T1 86CT, T2 96CT, T3 85CT, T4 6OG, T5 96OG, T6 85OG, T7 86CV, T8 96CV e T9 85CV, com delineamento estatístico de blocos ao acaso e quatro repetições. Os parâmetros químicos do solo analisados foram macronutrientes e micronutrientes; os parâmetros microbiológicos foram carbono da biomassa microbiana (CBM), respiração basal do solo (RBS), quociente metabólico (qCO2), número mais provável de fungos e bactérias do solo (NMP); e, por fim, a produtividade agrícola (t/ha). Os resultados foram submetidos a análise de variância (ANOVA) e à comparação das médias através do teste de Tukey (10%). Também foi realizada a análise de variância dos dados e correlação cofenética de Pearson para formação de dendogramas. Com base no período estudado, considerado como fase crítica da formação do canavial, concluiu-se que os parâmetros químicos que evidenciaram alterações no solo foram pH e os macronutrientes Mg, Al e SB, sendo os tratamentos orgânicos equivalentes e/ou melhores que os tratamentos convencionais. Para os parâmetros microbiológicos, o NMP de fungos apresentou os maiores valores nos tratamentos convencionais e controle. A produtividade agrícola não foi influenciada pelos diferentes tratamentos e insumos utilizados, independente da variedade de cana-de-açúcar utilizada. Por fim, foram observadas correlações positivas entre as variáveis CTC e quociente metabólico (qCO2) apontando potencial melhoria da qualidade do solo, com o emprego de insumos orgânicos / The environmental dynamics has limited recycling capacity and increasing use of agroindustrial waste, especially in agriculture, can lead to soil pollution situations and other environmental components. The maintenance of the productivity of agricultural and natural ecosystems is dependent on the transformation process of organic matter and therefore, the microbial biomass, which is responsible for the decomposition and mineralization of waste therein. The natural dynamics of soil microorganisms, constantly changing and adapting, makes them a sensitive indicator of changes resulting from different agricultural practices. So, knowing these changes and their interference is critical to identify appropriate management strategies, pointing appropriate use of techniques. The objective of this study was to evaluate the quality of an agricultural soil cultivated with three varieties of sugarcane (Saccharum spp.), comparing the use of mineral front fertilizer use of organic compound fertilizer at the end of training period of tillers (120 days after planting). Was deployed in field conditions, the sugarcane crop (plant cane), using the varieties RB 867515, RB 962 869 and RB 855 453, where each variety was grown in three different ways, namely: planting control (CT) without application of inputs for fertilizer; organic planting (OG) with organic fertilizer application; and conventional tillage (CV) with application of mineral fertilizer, following fertilizer recommendations after initial chemical analysis of the local soil. Each plot had 37 m2, with 5 grooves of 5.0 m long and 1.5 m spacing between lines, with the three central grooves forming the floor area. According to the variety and type of fertilization, they were formed nine treatments: T1 86CT, T2 96CT, T3 85CT, T4 6OG, T5 96OG, 85OG T6, T7 86CV, T8 96CV and T9 85CV, with statistical design of randomized blocks and four replications. Chemical parameters analyzed were macronutrients and micronutrients; microbiological parameters were microbial biomass carbon (MBC), the basal soil respiration (RBS), metabolic quotient (qCO2), most likely number of fungi and soil bacteria (NMP); and, finally, agricultural productivity (t/ha). The results were submitted to analysis of variance (ANOVA) and comparison of means by Tukey test (10%). It was also performed the analysis of variance of data and cophenetic Pearson correlation to dendograms training. Based on the study period, considered critical stage of the formation of sugarcane, it was concluded that chemical parameters showed changes in soil were pH and macronutrients Mg, Al and SB being equivalent organic treatments and/or better than those treatments conventional. For microbiological parameters, NMP fungi showed the highest values in conventional and control treatments. Agricultural productivity was not affected by the different treatments and inputs used, regardless of the variety of sugarcane used. Finally, positive correlations were observed between the CTC variables and metabolic quotient (qCO2) indicating potential improvement of soil quality, with the use of organic inputs
18

Efeito da aplicação de composto orgânico sobre a qualidade do solo cultivado com cana-de-açúcar (Saccharum spp.) / Effect of the application of organic compost on the soil quality cultivated with sugarcane (Saccharum spp.)

João Paulo Apolari 26 February 2016 (has links)
A dinâmica ambiental possui capacidade limitada de reciclagem e a crescente utilização resíduos agroindustriais, especialmente na agricultura, pode levar a situações de poluição do solo e demais componentes ambientais. A manutenção da produtividade de ecossistemas agrícolas e naturais depende do processo de transformação da matéria orgânica e, por conseguinte, da biomassa microbiana do solo, e que é responsável pela decomposição e mineralização de resíduos no mesmo. A dinâmica natural dos microrganismos do solo, em constante mudança e adaptação, os torna um indicador sensível às mudanças resultantes de diferentes práticas de manejo agrícola. Sendo assim, conhecer essas alterações e suas interferências é fundamental para identificar estratégias adequadas de manejo, apontando técnicas de utilização adequadas. O objetivo deste trabalho foi avaliar a qualidade de um solo agrícola, cultivado com três variedades de cana-de-açúcar (Saccharum spp.), comparando a utilização de adubação mineral frente à utilização de fertilizante orgânico composto no período final de formação dos perfilhos (120 dias após o plantio). Foi implantado, em condições de campo, o cultivo de cana-de-açúcar (cana planta), utilizando as variedades RB 867515, RB 962869 e RB 855453, onde cada variedade foi cultivada de três formas distintas, sendo elas: plantio controle (CT) sem aplicação de insumos para adubação; plantio orgânico (OG) com aplicação de fertilizante orgânico; e plantio convencional (CV) com aplicação de adubação mineral, seguindo recomendações de adubação após análise química inicial do solo local. Cada parcela possuía 37 m2, com 5 sulcos de 5,0 m de comprimento e espaçamento de 1,5 m entrelinhas, sendo os três sulcos centrais formando a área útil. De acordo com a variedade e o tipo de adubação, foram formados nove tratamentos: T1 86CT, T2 96CT, T3 85CT, T4 6OG, T5 96OG, T6 85OG, T7 86CV, T8 96CV e T9 85CV, com delineamento estatístico de blocos ao acaso e quatro repetições. Os parâmetros químicos do solo analisados foram macronutrientes e micronutrientes; os parâmetros microbiológicos foram carbono da biomassa microbiana (CBM), respiração basal do solo (RBS), quociente metabólico (qCO2), número mais provável de fungos e bactérias do solo (NMP); e, por fim, a produtividade agrícola (t/ha). Os resultados foram submetidos a análise de variância (ANOVA) e à comparação das médias através do teste de Tukey (10%). Também foi realizada a análise de variância dos dados e correlação cofenética de Pearson para formação de dendogramas. Com base no período estudado, considerado como fase crítica da formação do canavial, concluiu-se que os parâmetros químicos que evidenciaram alterações no solo foram pH e os macronutrientes Mg, Al e SB, sendo os tratamentos orgânicos equivalentes e/ou melhores que os tratamentos convencionais. Para os parâmetros microbiológicos, o NMP de fungos apresentou os maiores valores nos tratamentos convencionais e controle. A produtividade agrícola não foi influenciada pelos diferentes tratamentos e insumos utilizados, independente da variedade de cana-de-açúcar utilizada. Por fim, foram observadas correlações positivas entre as variáveis CTC e quociente metabólico (qCO2) apontando potencial melhoria da qualidade do solo, com o emprego de insumos orgânicos / The environmental dynamics has limited recycling capacity and increasing use of agroindustrial waste, especially in agriculture, can lead to soil pollution situations and other environmental components. The maintenance of the productivity of agricultural and natural ecosystems is dependent on the transformation process of organic matter and therefore, the microbial biomass, which is responsible for the decomposition and mineralization of waste therein. The natural dynamics of soil microorganisms, constantly changing and adapting, makes them a sensitive indicator of changes resulting from different agricultural practices. So, knowing these changes and their interference is critical to identify appropriate management strategies, pointing appropriate use of techniques. The objective of this study was to evaluate the quality of an agricultural soil cultivated with three varieties of sugarcane (Saccharum spp.), comparing the use of mineral front fertilizer use of organic compound fertilizer at the end of training period of tillers (120 days after planting). Was deployed in field conditions, the sugarcane crop (plant cane), using the varieties RB 867515, RB 962 869 and RB 855 453, where each variety was grown in three different ways, namely: planting control (CT) without application of inputs for fertilizer; organic planting (OG) with organic fertilizer application; and conventional tillage (CV) with application of mineral fertilizer, following fertilizer recommendations after initial chemical analysis of the local soil. Each plot had 37 m2, with 5 grooves of 5.0 m long and 1.5 m spacing between lines, with the three central grooves forming the floor area. According to the variety and type of fertilization, they were formed nine treatments: T1 86CT, T2 96CT, T3 85CT, T4 6OG, T5 96OG, 85OG T6, T7 86CV, T8 96CV and T9 85CV, with statistical design of randomized blocks and four replications. Chemical parameters analyzed were macronutrients and micronutrients; microbiological parameters were microbial biomass carbon (MBC), the basal soil respiration (RBS), metabolic quotient (qCO2), most likely number of fungi and soil bacteria (NMP); and, finally, agricultural productivity (t/ha). The results were submitted to analysis of variance (ANOVA) and comparison of means by Tukey test (10%). It was also performed the analysis of variance of data and cophenetic Pearson correlation to dendograms training. Based on the study period, considered critical stage of the formation of sugarcane, it was concluded that chemical parameters showed changes in soil were pH and macronutrients Mg, Al and SB being equivalent organic treatments and/or better than those treatments conventional. For microbiological parameters, NMP fungi showed the highest values in conventional and control treatments. Agricultural productivity was not affected by the different treatments and inputs used, regardless of the variety of sugarcane used. Finally, positive correlations were observed between the CTC variables and metabolic quotient (qCO2) indicating potential improvement of soil quality, with the use of organic inputs
19

Integration of Ozone and Ultrasound Activated Sludge Pre-Treatments into a Wastewater Treatment Whole-Plant Simulator

Musser, Jonathan January 2010 (has links)
Modern wastewater treatment provides great benefit to society by reducing the transmission of disease. In recent years computer simulation of whole plants has allowed for improved design and more economical consideration of alternatives. One new alternative for wastewater treatment is the pre-treatment of sludges, although this technology has not yet been adapted for computer simulation. This thesis describes research which was conducted to describe pre-treatments in terms appropriate for whole-plant computer models. Pre-treatment shows promise in terms of reducing sludge, a waste product the disposal of which can be costly depending on the applicable regulations. At the same time pre-treatment can improve the generation of biogas, which is readily converted to heat and/or electricity and can help to offset treatment energy requirements. Pre-treatments can be broadly categorized as physical, chemical, or thermal. For this study, ultrasound was selected as a model physical pre-treatment and ozone as a model chemical pre-treatment. The range of doses to be tested was obtained by reviewing earlier literature. Waste activated sludge was obtained from pilot reactors treating screened municipal wastewater. This sludge was subjected to a range of doses in batch reactors. Conventional laboratory analyses were used to determine the effects of pre-treatment on such parameters as chemical oxidant demand, solids, and various nitrogen fractions. As well, respirometry was utilized to estimate the biologically active and bioavailable fractions. A novel technique for analysis of respirometric data was developed, which consisted of fitting synthetic oxygen uptake rate curves to the measured data. Both ultrasound and ozone were observed to decrease the amount of active biomass present while increasing the amount of biodegradable material. The conversions between these fractions were modeled using simple functions of pre-treatment dose. For ultrasound, a conversion which exponentially decayed with respect to increasing ultrasound dose was used to relate these fractions. For ozone, the conversion from active biomass to slowly degradable material occurred more slowly than the conversion to rapidly degradable material; as such two conversions were modeled, each exponentially decaying with respect to dose but with different dose constants. The observed conversions were added to a whole-plant model and the implications of the models were considered for one simple wastewater treatment plant. Both pre-treatments showed a decrease in total sludge production and an increase in biogas production, as predicted by earlier research. Published full-scale results were not reported with sufficient detail to be replicated, and so a quantitative comparison was not possible.
20

Integration of Ozone and Ultrasound Activated Sludge Pre-Treatments into a Wastewater Treatment Whole-Plant Simulator

Musser, Jonathan January 2010 (has links)
Modern wastewater treatment provides great benefit to society by reducing the transmission of disease. In recent years computer simulation of whole plants has allowed for improved design and more economical consideration of alternatives. One new alternative for wastewater treatment is the pre-treatment of sludges, although this technology has not yet been adapted for computer simulation. This thesis describes research which was conducted to describe pre-treatments in terms appropriate for whole-plant computer models. Pre-treatment shows promise in terms of reducing sludge, a waste product the disposal of which can be costly depending on the applicable regulations. At the same time pre-treatment can improve the generation of biogas, which is readily converted to heat and/or electricity and can help to offset treatment energy requirements. Pre-treatments can be broadly categorized as physical, chemical, or thermal. For this study, ultrasound was selected as a model physical pre-treatment and ozone as a model chemical pre-treatment. The range of doses to be tested was obtained by reviewing earlier literature. Waste activated sludge was obtained from pilot reactors treating screened municipal wastewater. This sludge was subjected to a range of doses in batch reactors. Conventional laboratory analyses were used to determine the effects of pre-treatment on such parameters as chemical oxidant demand, solids, and various nitrogen fractions. As well, respirometry was utilized to estimate the biologically active and bioavailable fractions. A novel technique for analysis of respirometric data was developed, which consisted of fitting synthetic oxygen uptake rate curves to the measured data. Both ultrasound and ozone were observed to decrease the amount of active biomass present while increasing the amount of biodegradable material. The conversions between these fractions were modeled using simple functions of pre-treatment dose. For ultrasound, a conversion which exponentially decayed with respect to increasing ultrasound dose was used to relate these fractions. For ozone, the conversion from active biomass to slowly degradable material occurred more slowly than the conversion to rapidly degradable material; as such two conversions were modeled, each exponentially decaying with respect to dose but with different dose constants. The observed conversions were added to a whole-plant model and the implications of the models were considered for one simple wastewater treatment plant. Both pre-treatments showed a decrease in total sludge production and an increase in biogas production, as predicted by earlier research. Published full-scale results were not reported with sufficient detail to be replicated, and so a quantitative comparison was not possible.

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