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1
Vaartnou, Manivalde. "EPR investigation of free radicals in excised and attached leaves subjected to ozone and sulphur dioxide air pollution." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29444.
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The X-band EPR spectrometry system was modified to allow for the in situ monitoring of free radical changes in attached, intact plant leaves, which were caused by stress factors such as exposure to excessive photon flux density, ozone or sulphur dioxide. This was done through use of the dewar insert of the variable temperature accessory as a guide, the construction of 'T' shaped cellulose acetate holders to which leaves could be attached with adhesive tape, and modification of the gas flow system used for controlled temperature studies.
Kinetic studies of free radical formation were possible with leaves which had minimal underlying Fe⁺⁺ and Mn⁺⁺ signals. In leaves with large underlying signals a Varian software program was used to subtract overlapping signals from each other, thereby revealing the free-radical signal changes which occurred under different light regimes and stress conditions. Preliminary investigation disclosed the formation of a new signal upon prolonged exposure to far-red light and the effect of oxygen depletion upon photosynthetic Signals I and II.
Leaves subject to high photon flux density reveal an unreported free-radical signal, which decays upon exposure to microwave radiation; and concomitant damage to Photosystems I and II. Upon elimination of this signal leaves return to the undamaged state or reveal permanent damage to either photo-system, depending upon the degree of damage.
Kentucky bluegrass and perennial ryegrass leaves subject to low levels of ozone (up to 80ppb) for periods of 8 hours show no changes in free-radical signal formation. At intermediate levels of ozone (80-250ppb) a new free-radical signal was formed within 3 hours of fumigation, Signal II was decreased and Signal I decayed. These changes were reversible if fumigation was terminated. At fumigation levels exceeding 250ppb a different new irreversible free-radical signal was formed in darkness within 1.5 hours of fumigation.
Radish, Kentucky bluegrass and perennial ryegrass leaves subject to high levels of sulphur dioxide (10-500ppm) reveal the formation of Signal I upon irradiation with broad-band white or 650nm light, thereby indicating an interruption of normal electron flow from PSII to PSI. Damage to the oxygen-evolving complex and reaction centre of PSII is also revealed through changes in Signal II and the Mn⁺⁺ signal. These changes in the normal EPR signals are dose-dependent. Leaves subject to low levels of sulphur dioxide (600-2000ppb) reveal the disappearance of Signal I after 3 hours of fumigation and the formation of a new free-radical signal with parameters similar to the sulphur trioxide free-radical signal. These latter changes are partially reversible upon termination of fumigation.
After prolonged exposure to either ozone or sulphur dioxid a free-radical signal with parameters similar to the superoxid anion free-radical signal is formed in plant leaves.Land and Food Systems, Faculty of
Graduate
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McLaughlin, Kirsty Elizabeth. "The effect of underwater noise pollution on fish." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.695677.
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Anthropogenic noise is a global pollutant, present in both terrestrial and aquatic ecosystems. Due to high species diversity and the characteristics of sound propagation in water, noise pollution in aquatic environments may be more detrimental than in terrestrial environments. Underwater noise affects the behaviour of mammals, fish and invertebrates, with changes to communicative and spatial behaviour among those frequently reported. However, relatively little work examining the effect of underwater noise on reproductive behaviour has been completed. Reproduction is essential for the proliferation of life. Therefore, investigating how anthropogenic noise may affect it is important. I used the biparental species, Amatitlania nigrofasciata, as a model system to study the effect of underwater noise pollution on multiple stages of reproduction. Using playback experiments, I firstly tested the effect of short-term noise on behaviour and then examined the effect of longer-term noise on: (1) pairing behaviour, (2) nest-site selection, (3) parental defence, (4) parental care and (5) reproductive success. I found that both short-term and long-term noise affected behaviour and that behaviour was affected throughout the reproductive cycle. I also established noise as a proximate factor influencing nest-site selection and provide evidence for multiple mechanisms through which noise could affect behaviour. However, behavioural changes in response to noise did not translate into negative consequences for reproductive success. Noise increased parental investment, by increasing parental defence and brood provisioning behaviour. This could reduce the resources parents can invest in subsequent broods. Therefore, noise may affect the reproductive success of future breeding attempts. My findings provide novel insight into how changes to the acoustic environment affect reproductive behaviour.
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Álvarez, Simón Daniel. "Effect of environmental pollution on asthma due to soybean." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/457984.
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La soja es uno de los cultivos más valiosos del mundo y una importante fuente tanto de proteína vegetal como de aceite, pero también, es una causa de asma. En ciudades con puertos donde se carga o descarga soja, se han descrito brotes epidémicos de asma por soja. La medición de los niveles de aeroalérgenos de soja con métodos altamente sensibles es esencial en la evaluación de los riesgos para la salud que estos implican. En la actualidad, los aeroalérgenos de soja se cuantifican mediante ensayos ELISA que deben ser realizados en un laboratorio por personal especializado. Metodologías menos laboriosas, baratas y sencillas para medir los niveles de alérgenos de soja podrían ser una herramienta extremadamente útil. Por lo tanto, se ha investigado el desarrollo y rendimiento de un test rápido para la detección de aeroalérgenos de soja en muestras ambientales.
El test rápido desarrollado detectó un amplio rango de concentraciones de aeroalérgenos de soja cuya interpretación visual tenía un grado de acuerdo substancial entre evaluadores independientes, una buena concordancia con los resultados obtenidos mediante ELISA, una buena correlación con los resultados de densitometría y una sensibilidad y especificidad adecuadas. El test desarrollado es rápido, sencillo y tiene un potencial considerable en el campo de la monitorización ambiental de los niveles de aeroalérgenos de soja. Debido a su simplicidad, este test rápido puede ayudar a mejorar el manejo de pacientes alérgicos a la soja, permitiendo controlar la exposición a los alérgenos ambientales sin la necesidad de tecnología o personal especializado.
Aunque la comprensión de la patogénesis del asma alérgico ha aumentado sustancialmente, y la monitorización de los niveles de aeroalérgenos ha demostrado ser una medida eficaz, todavía existen pequeñas lagunas en nuestra comprensión del asma por soja. Todavía no se conoce cómo la contaminación puede interactuar, o modificar el efecto, de los alérgenos de soja. Las partículas diésel (DEP) son la fracción sólida de la mezcla compleja que genera un motor diésel y uno de los contaminantes antropogénicos más prevalentes en todo el mundo. La investigación en las últimas décadas ha proporcionado resultados que sugieren que las DEP puede incrementar la respuesta asmática producida por alérgenos, pero la capacidad de las DEP para hacerlo parece depender de una amplia gama de variables y el mecanismo subyacente todavía no se conoce en profundidad.
El desarrollo de un modelo murino de exposición combinada a soja y DEP puede aumentar nuestra comprensión de la contribución de las DEP al desarrollo y exacerbación del asma, así como, de los mecanismos subyacentes a estos procesos.
Este estudio con la estandarización de un nuevo modelo murino de asma y la evaluación del efecto combinado de los aeroalérgenos de soja y las DEP, muestra que la administración continua de alérgenos de soja a una cierta concentración es capaz de desencadenar una respuesta asmática. Además, también demuestra que la coexposición a los alérgenos de soja y las DEP puede producir una mayor respuesta asmática, aumentando la hiperreactividad de las vías respiratorias y la inflamación pulmonar incluso cuando la concentración de alérgeno de soja es incapaz por si sola de provocar una respuesta inflamatoria. Este modelo proporciona nuevas evidencias que apoyan que el mecanismo subyacente en el asma por soja es una respuesta mixta Th2/Th17, y también que las DEP son capaces de potenciar el efecto alergénico de la soja a través de un mecanismo mediado por Th17. Estos hallazgos sugieren que la monitorización de partículas como alternativa a la valoración de la exposición a las DEP puede ser una adición útil a la monitorización de alérgenos dentro de las estrategias de prevención de nuevos brotes de asma.Soybean is one of the most valuable crops in the world, a major source of vegetable protein and oil, but also, a cause of asthma. In cities with ports where soybean is loaded or unloaded, community outbreaks of asthma have been described and attributed to inhalation of soybean dust. Measuring soybean aeroallergens levels with highly sensitive methods is essential in the assessment of health risks due to these airborne substances. Currently, soybean aeroallergens exposure in the environment is monitored using ELISA assays which must be evaluated in a specialized laboratory by skilled personnel. Cost-efficient, less labor-intensive technological procedures for monitoring soy allergens levels can be a very useful tool. Consequently, the development, performance and suitability of a rapid test for the detection of soybean aeroallergens in environmental samples was investigated. The rapid test developed detected a wide range of soybean aeroallergen concentrations with a substantial agreement in visual assay interpretations between independent evaluators, a good concordance with ELISA results, a strong correlation with densitometry results, and adequate sensitivity and specificity. The strip assay developed is rapid, simple, and has considerable potential in the environmental monitoring field for screening soy aeroallergens levels in port cities where allergen measurements are not currently performed. Due to its simplicity, the test will improve the management of soy allergic patients by controlling environmental allergen exposure without the need for apparatus or skilled personnel. Although the understanding of allergic asthma pathogenesis has increased substantially, and the effect of aeroallergen assessment shows to be effective, our current understanding about soybean asthma has some knowledge gaps, as is to know how pollution can interact or modify the effect of soybean allergens. Diesel exhaust particles (DEP) are the solid fraction of the complex mixture of diesel exhaust, and one of the most prevalent anthropogenic pollutants worldwide. Research over recent decades has provided very informative results, and has suggested that DEP can enhance allergen-driven asthmatic immunopathology, but the ability of DEP to do so appears highly dependent on a wide range of variables, and the underlying mechanism remains unclear. The experimental modelling of asthma, particularly the development of murine models, besides being very useful to further investigate the pathogenesis of the disease, can contribute to a deeper understanding of the effects of DEP over asthma. The development of a murine model of combined exposure to soybean and DEP can provide new insights to increase our understanding of the contribution of DEP to asthma development, exacerbation and the mechanisms underlying these processes. This study with the standardization of a novel murine model of asthma and the assessing of the combined effect of soybean aeroallergens and DEP, shows that the continuous administration of soybean allergens at a certain concentration is capable of triggering an asthmatic response. In addition, it also demonstrates that the coexposure to soybean allergens and DEP results in a stronger asthmatic response, increasing airway hyperresponsiveness and pulmonary inflammation even when the concentration of soybean allergen is incapable of promoting an inflammatory response by itself. This mouse model provides evidence that the mechanism underlying soybean asthma is a mixed Th2/Th17 response, and also that DEP is capable of enhancing the allergenic effect of soybean through a Th17-mediated mechanism. These findings suggest that particulate matter monitoring as a surrogate of DEP exposure may be a useful addition to the allergen monitoring in the attempt to prevent new asthma outbreaks.
4
Karr, Catherine J. "The effect of ambient air pollution on infant bronchiolitis /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10945.
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Clark, Nina Annika. "Effect of ambient air pollution on development of childhood asthma." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2400.
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Asthma prevalence is increasing worldwide and the causes of this increase are largely unknown. There is increasing recognition of the importance of early environmental exposures in childhood asthma development. Outdoor air pollution has been shown to trigger asthma symptoms but its role in incident disease remains controversial. To address these questions, I investigated the effect of in utero and first year of life exposure to ambient air pollution on risk of asthma diagnosis in a nested case-control study.
All children born in Southwestern British Columbia in 1999 and 2000 (N=37,401) were assessed for incidence of asthma diagnosis at age 3 - 4 years using hospitalization and primary physician records. Exposure to ambient air pollution was estimated for the gestational period and first year of life using high-resolution pollution surfaces derived from government monitoring station data as well as land use regression models adjusted for temporal variation. Conditional logistic regression analyses were used to estimate effects of CO, NO, NO₂, PM₁₀, PM₂.₅, O₃, SO₂, black carbon, wood smoke and proximity to roads and point sources on asthma diagnosis.
Elevated risks of asthma diagnosis were observed with increased early life exposure to CO, NO, NO₂, PM₁₀, SO₂, black carbon and proximity to point sources. Effects were generally larger for first year exposures than in utero exposures, and larger for girls than boys.
The results indicate that early life exposure to air pollution is associated with increased risk of asthma diagnosis in early childhood. Although the effect sizes are small, air pollution exposure in urban areas is ubiquitous so may have significant effects at the population level. These results should be confirmed when children are older and asthma diagnosis is more robust.
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Loth, Kevin William. "The effect of air pollution on hayfever in the UK." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284005.
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Chernicharo, Carlos Augusto de Lemos. "The effect of temperature and substrate concentration on the performance of U.A.S.B. reactors." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308963.
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Al-Rasheid, Khaled A. S. "The effect of heavy metals on the marine ciliate Euplotes mutabilis (Tuffrau, 1960)." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358875.
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Loo, Hui. "Effect of surface waves on pollutant dispersion." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23273185.
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Parnia, Sam. "The effect of particulate matter pollution on bronchial epithelial cell responses." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437882.
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Pažitka, Marek. "Economics of Family: Effect of Air Pollution on Sex of Children." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-194209.
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The Trivers-Willard hypothesis (TWH) states that parents in good conditions will bias the sex ratio toward sons and parents in poor conditions will bias the sex ratio toward daughters. The present study contributes to literature in several ways: a large, general, country population data set (N= 1 401 851) from modern contemporary society; first study in the Czech Republic; an inclusion of air pollution into the TWH estimation; and a more detailed focus on stillbirths. With the natality microdata from the Czech Statistical Office and data concerning the level of air pollution in the Czech Republic from the Czech Hydrometeorological Institute, I analyze if the biological and socio-economics status of mothers and the characteristics of our surroundings (air pollution) affect the sex of children. The results are insignificant or not robust across specifications. I identified three hypotheses which are most likely the reason for the insignificant results: a non-inclusion of the biological and socio-economical status of a father, insufficient diversity or evolutionarily novel environment in the Czech Republic. As a conclusion, the presented evidence suggests that stillbirths are random in the Czech Republic and that the sex ratio is not affected by the socio-economics status of mothers or the characteristics of our surroundings (pollution).
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Lee, Mihye. "The Effect of Climate Change and Air Pollution on Public Health." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14117765.
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The effects of temperature and air pollution on public health are comprehensive and ubiquitous. Therefore, this dissertation deals with the comprehensive topic of climate change and air pollution and their effects on public health.
The first chapter examines the effect of temperature on mortality in 148 cities in the U.S. from 1973 through 2006. We focused on the timing of exposure to unseasonal temperature and temporal and spatial acclimation.
The second chapter incorporated AOD data from satellite imagery with other predictors such as meteorological variables, land use regression, and spatial smoothing to predict the daily concentration of PM2.5 at a 1 km2 resolution across the southeastern United States, covering the seven states of Georgia, North Carolina, South Carolina, Alabama, Tennessee, Mississippi, and Florida for the years from 2003 through 2011.
As the sequel of the result from the second chapter, the last chapter investigated the acute effect of PM2.5 on mortality in the entire population of North Carolina, South Carolina, and Georgia between 2007 and 2011 using the predictions from the second topic as PM2.5 exposure.
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Dando, Chrtistine. "The effect of zinc on physiological function in Gammarus pulex : a between-individual variation approach." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274947.
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Shaw, Peter James. "The effect of humic substances on the speciation and bioavailability of iron and phosphate in lakes." Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239867.
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Tennakoon, Nihal Ananda. "Effect of heavy metal contaminated sewage sludge on biological and chemical properties of coniferous forest soils." Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU549118.
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A field study was carried out at Ardross forest, northern Scotland where heavy metal contaminated sewage sludge had been applied to a peaty podzol at rates of 500 (low) and 1000 (high) kg N ha-1 before tree (Sitka spruce) planting. Nitrogen mineralisation rates determined by field incubation of sealed cores ranged from 3.7 to 4.5 and 7.3 to 9.4 kg N h-1 over the growing season (May to September, 1991) in soils amended with low and high rates of sludge respectively. For the control soil, to which no sludge had been added, mineralisation rates ranged from 2.4 to 2.9 kg N ha-1. Mineralisation of residual sludge was estimated to be 0.56&'37 and 1.14&'37 in 1991, 8 years after sludge application at the low and high rates, respectively. Soils brought back to the laboratory and repacked according to the field profile enabled microcosm studies to be carried out to further investigate possible changes caused to N-cycling processes in coniferous forest soil due to application of heavy metal contaminated sewage sludge, and to consider possible mechanisms of any such changes. In the microcosm study, the two rates of application of sewage sludge increased N mineralisation. A linear relationship was apparent between N mineralisation and the rate of sludge application. Increased N mineralisation was associated with an increase in active fungal mycelium, biomass N and soil animal population densities. The availability of Cd, Cu, Mn, Pb and Zn was found to be related to the time of the year, with highest availability in Spring and Summer, and lowest availability in Winter. There was no evidence of any adverse effects in terms of heavy metals on the studied biological parameters and mineralisation rates in the field and microcosm studies. Total N, pH and moisture also increased due to sludge application.
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Tessier, Catherine. "Ecotoxicological impacts of zebra mussels, Dreissena polymorpha, a new food source for lesser scaup, Aythia affinis." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34468.
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Zebra mussels (Dreissena polymorpha) have invaded a great proportion of the waters of the eastern part of North America. This mollusk may be a useful sentinel species for bioaccumulation of heavy metals and organic contaminants in aquatic ecosystems. The zebra mussel's capacity to bioaccumulate cadmium at environmentally relevant exposure and to sequester metals in metal-binding proteins, metallothioneins, was investigated. Elevated (relative to control) concentrations of Cd$ sp{2+}$ were detected in Dreissena exposed to $ ge$2 $ mu$g Cd/liter suggesting that zebra mussels cannot regulate Cd$ sp{2+}$ of trace exposure concentration. More than 85% of the measured Cd$ sp{2+}$ was bound to metallothioneins.Lesser scaup (Aythya affinis) was assessed as a model species for potential impacts of zebra mussels on higher trophic levels. The feasibility of incubating and rearing scaup in semi-natural conditions was evaluated. A series of biomarkers was assessed in 3 groups of scaup fed a contaminant-free diet or diets containing zebra mussels from the St-Lawrence River or Lake Erie.
Lesser scaup proved to be a suitable species to raise in captivity providing daily water misting through out incubation and strict hygiene conditions during brooding. A hatching success of 89% was achieved. Appropriate housing, feeding and bathing conditions yielded low (3%) post-hatching mortality.
Phagocytosis and respiratory burst activities of heterophils of scaup were suppressed after 6 weeks of feeding on zebra mussels, compared to the control group. These two heterophilic functions were negatively correlated with the incidence of pododermatitis (bacterial feet infection), suggesting a suppression of the non specific immunity. Increased liver/body mass ratio and decreased hepatic vitamin A (retinol and retinyl palmitate) concentrations were observed in scaups fed zebra mussels. Lipid accumulation and glycogen overload were found in the livers of scaups fed mussels from the St-Lawrence River and the Lake Erie groups, respectively. These immunological, biochemical and histopathological biomarkers show promise for monitoring "early" injury and may help in the understanding of health impairment of different species of waterfowl exposed to xenobiotics via contaminated food sources.
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Thouron, Laëtitia. "Modélisation dynamique multi-échelle de la pollution atmosphérique en milieu urbain." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1206/document.
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La pollution atmosphérique en milieu urbain a été identifiée comme une cause importante d’impacts sanitaires, y compris de décès prématurés. En particulier, les concentrations ambiantes de polluants gazeux tels que le dioxyde d’azote (NO2) et de particules (PM10 et PM2,5) sont réglementées, ce qui implique que des stratégies de réductions d’émissions doivent être mises en place pour diminuer ces concentrations dans les lieux où la réglementation correspondante n’est pas respectée. Par ailleurs, la pollution atmosphérique peut contribuer à la contamination d’autres milieux, par exemple à travers la contribution des dépôts atmosphériques à la contamination des eaux de ruissellement.Les aspects multifactoriels et multiéchelle de la pollution en ville rendent l’identification des sources difficile. En effet, le milieu urbain est un espace hétérogène caractérisé par des structures architecturales complexes (bâti ancien côtoyant un bâti plus moderne, zones résidentielles, commerciales, industrielles, axes routiers…), des émissions de polluants atmosphériques non uniformes et par conséquent une exposition de la population à la pollution qui est variable dans l’espace et le temps.La modélisation de la pollution atmosphérique urbaine a pour vocation de comprendre l’origine des polluants, leur étendue spatiale et leur niveau de concentrations/dépôt. Certains polluants ont des temps de résidence long et peuvent séjourner plusieurs semaines dans l’atmosphère (PM2,5) et donc être transportés sur de longues distances, d’autres au contraire, sont plus locaux (NOx en proximité du trafic). La répartition spatiale d’un polluant dépendra alors de plusieurs facteurs et notamment des surfaces rencontrées. La qualité de l’air, elle, dépend fortement des conditions météorologiques, du bâti (rue-canyon) et des émissions.L’objectif de cette thèse est de traiter certains de ces aspects en modélisant : (1) la pollution urbaine de fond avec un modèle de chimie-transport (Polyphemus/POLAIR3D), qui permet d’estimer les dépôts de polluants atmosphériques par type de surfaces urbaines (toits, murs et chaussées), (2) la pollution à l’échelle de la rue en intégrant explicitement les effets du bâti de manière tridimensionnelle avec d’une part un modèle multiéchelle de chimie-transport (SinG) et d’autre part un modèle de mécanique des fluides (Code_Saturne) et (3) un processus de micro-échelle qui est la réémission des particules présentes sur la chaussée par le trafic routier avec trois formulations différentes (déterministe, semi-empirique et empirique). L’intérêt de cette thèse est de pouvoir comparer et évaluer l’opérabilité et la performance de plusieurs modèles de qualité de l’air à plusieurs échelles (région, quartier et rue) afin de mieux appréhender la caractérisation de la qualité de l’air en milieu urbainUrban air pollution has been identified as an important cause of health impacts, including premature deaths. In particular, ambient concentrations of gaseous pollutants such as nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) are regulated, which means that emission reduction strategies must be put in place to reduce these concentrations in places where the corresponding regulations are not respected. Besides, air pollution can contribute to the contamination of other media, for example through the contribution of atmospheric deposition to runoff contamination.The multifactorial and multiscale aspects of urban make the pollution sources difficult to identify. Indeed, the urban environment is a heterogeneous space characterized by complex architectural structures (old buildings alongside a more modern building, residential, commercial, industrial zones, roads, etc.), non-uniform atmospheric pollutant emissions and therefore the population exposure to pollution is variable in space and time.The modeling of urban air pollution aims to understand the origin of pollutants, their spatial extent and their concentration/deposition levels. Some pollutants have long residence times and can stay several weeks in the atmosphere (PM2.5) and therefore be transported over long distances, while others are more local (NOx in the vicinity of traffic). The spatial distribution of a pollutant will therefore depend on several factors, and in particular on the surfaces encountered. Air quality depends strongly on weather, buildings (canyon-street) and emissions.The aim of this thesis is to address some of these aspects by modeling: (1) urban background pollution with a transport-chemical model (Polyphemus / POLAIR3D), which makes it possible to estimate atmospheric pollutants by type of urban surfaces (roofs, walls and roadways), (2) street-level pollution by explicitly integrating the effects of the building in a three-dimensional way with a multi-scale model of transport chemistry (SinG) and (3) a microscale process which is the traffic-related resuspension of the particles present on the road surface with three different formulations (deterministic, semi-empirical and empirical).The interest of this thesis is to compare and evaluate the operability and performance of several air quality models at different scales (region, neighborhood and street) in order to better understand the characterization of air quality in an urban environment
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Botha, Amanda Theophila. "Assessment of air pollution impacts on vegetation in South Africa." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54495.
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Field surveys and biomonitoring network experiments were conducted in selected areas in South Africa to assess possible air pollution damage to vegetation. During field surveys, atmospheric fluoride was identified as an important pollutant that damaged vegetation in residential areas north of Cape Town. Gaseous air pollutants, including acid deposition and acidic mist, probably play a major role in the development of characteristic air pollution injury symptoms observed on pine trees in the Eastern Transvaal area.
The impact of urban air pollution in the Cape Town area was evaluated by exposing bio-indicator plants in a network of eight biomonitoring network stations from June 1985 to May 1988. Sensitive Freesia and Gladiolus cultivars were used to biomonitor atmospheric fluoride, while a green bean cultivar was used as a biomonitor of atmospheric sulphur dioxide and ozone. At one location, bio-indicator plants were simultaneously exposed in a biomonitoring network station (plant cages), open-top chambers (filtered and unfiltered), as well as in open plots. The responses of plants grown under these different conditions were compared.
During both the winter and summer seasons, ambient fluoride concentrations were estimated to be particularly high at the Loumar biomonitoring station (eastern side of Cape Town), as compared to that at the other biomonitoring stations. Elevated levels of atmospheric fluoride, as well as sulphur dioxide, appeared to prevail in the vicinity of industries located in the northern suburbs of Cape Town (Bothasig, Table View and Edgemead). Interveinal bleaching, which is characteristic of sulphur dioxide injury, was regularly observed on bean plants exposed at the Bothasig biomonitoring station and was usually determined to be significantly worse at this location than at the other biomonitoring stations. These results were confirmed by the evaluation of foliar sulphur content
Ambient pollutant concentrations appeared to be effectively reduced inside filtered open-top chambers, as exemplified by higher biomass production and lower foliar fluoride and sulphur levels in the relevant bio-indicator species, compared to that of plants grown in the open plots.
The methodology used during this research provided baseline data of the impact of air pollution on vegetation in South Africa which, in the absence of networks of sophisticated state of the art equipment, can be applied to aid in air pollution control strategies.Ph. D.
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Warwick, Oliver William Tindle. "The use of a biomarker to assess the effect of xenobiotic exposure on the freshwater invertebrate Gammarus pulex." Thesis, University of Sheffield, 1997. http://etheses.whiterose.ac.uk/10191/.
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Contamination of freshwaters is of concern because of its effect on ecosystem health. The effect of contamination can be assessed at all levels of biological organisation, from the ecosystem level to the molecular level. At the biochemical level, enzymes that are involved in the detoxification of organic chemical contaminants are useful as markers of contaminant exposure as they are often one of the first systems to respond to chemical exposure. Furthermore, changes in the activity of these enzymes may be indicative of effects at higher levels of biological organisation. In this study, the use of the detoxification enzyme glutathione stransferase (E. C. 2.5.1.18) (GST) in the freshwater invertebrate Gammarus pulex (Crustacea: Amphipoda), as a biomarker of organic xenobiotic exposure and effects was assessed. Toxicant induced changes in GST activity were related to changes in energy status and physiological energetics. A GST assay was developed that allowed the rapid analysis of GST activity in up to ninety individual animal samples simultaneously. Optimum sample handling and assay conditions were determined for the assay of GST in G. pulex, and extrinsic factors (e. g. environmental temperature, feeding and holding conditions) and intrinsic factors (e. g. body size), affecting variability of GST activity in G. pulex were assessed The effect of exposure to the organic xenobiotics lindane( an organochlorinein insecticide) and alcohol ethoxylate( a non-ionic surfactand detergent)on GST activity in G.pulex was described. The magnitude and duration of the response of GST activity to exposure to both chemicals was assessed under laboratory conditions and with alcohol ethoxylateu, sing outdoor artificial streams. The use of GST as a marker of pesticide exposure in field populations of G. pulex that were subject to pesticide contamination was studied in comparison with animals from non-contaminated, reference sites. The differences in GST activity between animals from a contaminated site and clean site were investigated by short-term and long-term exposure to lindane in the laboratory. Changes in energy status and physiological energetics were investigated in G. pulex on exposure to lindane by measuring glycogen concentration and scope for growth. Measuring these parameters on short-term and long-term exposure to lindane allowed the sensitivity of these responses to be related to the GST response and allowed the energetic cost of exposure to be assessed. It was concluded that increase in GST activity may providea rapid and sensitive biomarker of xenobiotic exposure in the short-term and in populations subject to pesticide contamination. The affect on GST activity may be indicative of effects at higher levels of biological organisations, such as scope for growth and glycogen concentration However, GST activity is affected by a variety of intrinsic and extrinsic factors and should therefore be used only asp art of a comparative study. Because of the transient nature of the GST response in situ assessments should be based on 24-hour exposure periods.
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Riain, CaitriÌona MaÌire NiÌ. "An investigation of the effect of external flow and pollution concentration fields on the infiltration of pollution into naturally ventilated buildings." Thesis, University of Westminster, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433761.
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Al-Kandari, Mariam Hussain Murad. "Evaluation of the effect of air pollution on human health in Kuwait." Thesis, London School of Hygiene and Tropical Medicine (University of London), 1994. http://researchonline.lshtm.ac.uk/1620626/.
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Even before the 1990 war the populations of some areas of Kuwait was subject to severe atmospheric pollution. However, little was known about the effect of this pollution on health and on the use of health care. Three areas in Kuwait were chosen for study which were demographically similar and lay at a different distances to the north (i.e. usually downwind) of the industrial area. Plant in this area emits hydrogen sulphide, sulphur dioxide, hydrocarbons, nitrogen oxides, ammonia and carbon monoxide among other pollutants. A special survey was carried out to gather information on demographic, health and lifestyle factors including age, sex, place of residence, smoking, physical symptoms, psychological effects, life satisfaction, environmental problems, experience of air pollution and use of health care. A random sample of 136 households (1140 persons) was chosen from the three areas and studied over the period from lst February 1988 to 31st January 1989. Data on levels of pollution concentrations and meteorological conditions were also collected over the same period for each area studied. Data on use of health care were available from the health centres in the three areas studied and also from the population survey. The demographic similarity of the three areas studied was generally confirmed by the data from population survey. The relationships involved were examined for different age groups using cross tabulation, time series analysis and regression analysis. There were clear gradients with increased distance from the industrial area in levels of pollution, levels of selfreported physical and psychological symptoms and in the use of health care. Of the individual pollutants it appeared that carbon monoxide levels were most closely correlated with levels of symptoms. For those aged less than 18, the link to CO was closest for respiratory symptoms, while for those aged 18 to 64 the link was with headache. The use of primary care is more closely linked to H2S although this relationship is relatively weak. Consider the relationship between levels of pollution in the three areas studied and Kuwait City and the levels of pollution in Shuaiba area taking meteorological conditions into account. The purpose of this was to allow for estimates of the effect of pollution reduction in Shuaiba on the health of population elsewhere in the country. However, no way was and of making such estimates with sufficient prison. This analysis confirmed a number of recommendations that have been made by others.
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Nazareth, Cheryl. "INVASIVE SPECIES AND PANNE ECOSYSTEMS: THE EFFECTS OF ATMOSPHERIC POLLUTION." Thesis, Connect to resource online, 2008. http://hdl.handle.net/1805/1611.
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Thesis (M.S.)--Indiana University, 2008.Title from screen (viewed on April 23, 2008). Department of Earth Sciences, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Gabriel M. Filippelli, Catherine J. Souch, Gary D. Rosenberg. Includes vitae. Includes bibliographical references (leaves 85-87).
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盧慧 and Hui Loo. "Effect of surface waves on pollutant dispersion." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31224866.
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Al-Alawi, Zahra Sadiq. "Effect of treated BAPCO oil refinery effluents on the marine environment in Bahrain." Thesis, University of Stirling, 1989. http://hdl.handle.net/1893/21524.
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The aim of this thesis was to study the effect of the treated oil refinery effluents of Bahrain Petroleum Company ( BAPCO ) on the marine environment. The study has been carried out in seven chapters, the first de~ling with general introduction about the physical environment of the Arabian Gulf and its oil industry in addition to marine pollution and fishery in Bahrain. The second chapter was aimed at studying the quality of water at different areas in Bahrain to compare it with the quality of water at an area adjacent to the refinery outfalls. The third chapter deals with the impact of the refinery on the marine environment. The research approach adopted was ecological and observational I involving water and sediment analysis. The fourth chapter was aimed at studying the effects of the refinery effluents on the fish through toxicity tests and estimation of trace metals and hydrocarbons in the fish tissues. The studies were conducted with several effluents from the main and side streams of the refinery, outlets of the induced air flotation unit and Sitra separator. The fifth chapter was aimed at studying the effect of Sitra oil storage tanks treated effluent on the intertidal fauna of the adjacent area. The sixth chapter deals with a general discussion on the whole studies. While the seventh chapter deals with sions and recommendations. From the study conducted , it could be said that in general the water quality of the western and northern regions of Bahrain is better than the water quality of the eastern region. The east has in general higher pH, higher ammonia, higher nitrite, lower nitrate, and higher phosphate levels than the other regions. The higher concentrations of all these substances reflects the urbanisation and industrialisation of this part of Bahrain and the consequent discharges of waste material. The fish, safee, were tested with different concentrations of the refinery main stream effluent using both short and long term exposures. The same experiment was set up using effluents from the side stream, the I.A.F. discharge of the refinery and Sitra separator outlet. The results indicated a greater toxicity of pollutants in the I.A.F. and Sitar separator effluents than in the main and the side stream effluents. The lethal concentration of I.A.F. and Sitra separator effluents which brought death to fifty percent of the test population of fish (safee) within 96 hours was approximately twenty percent. Fish from the experimental media showed a higner concentration of heavy metals. The study of the effect of Sitra oil storage tanks treated effluent on the intertidal fauna of the adjacent area revealed that no fauna was found at stations located just outside the effluent outlet. The sediment of these stations was black, slimy, heavily oiled with a bad smell and contains dead shells and turrets. Away from the effluent, a diverse fauna was found. It is concluded that the BAPCO refinery has a measurable impact on the marine environment of the east coast of Bahrain, and recommenqations are made tor the development of future policies with regard to Bahraini coastal waters.
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Redick, Melinda. "Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles." Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3119/.
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This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the hypotheses. Although the rate of predation was lower, tadpoles exposed to higher Cu concentrations were on average, 1.47 cm in total body length. Those exposed to 0.93 mg/L averaged 0.86 cm. After being placed into clean water, treatment tadpoles recovered after 20 days.
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Snelgrove, Paul V. R. "Pollution detection models and habitat preference of the cryptofauna associated with the coral Madracis Mirabilis." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66126.
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Singh, Ajit. "Quantifying the effect of atmospheric pollution and meteorology on visibility and tropospheric chemistry." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7828/.
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There are two distinct research foci within this thesis; the role of aerosol particle and trace gases on (i) visibility and (ii) tropospheric chemistry. This work investigates short and long term visibility, by exploring the combined influence of atmospheric aerosol and meteorology. Observations were fitted to a newly developed light extinction model to generate predictions of historic aerosol and gas scattering and absorbing properties, explaining long term visibility trends and their dependence on meteorological conditions. This model incorporates parameterizations of aerosol hygroscopicity, gas absorption and particle concentration, scattering, and absorption. Historical visibility data can therefore be used to assess trends in aerosol particle properties for time periods when observational data are scarce or non-existent. Short term visibility variations caused by particulate matter from firework and bonfire emissions is presented. It is shown that a reduction in the atmospheric visibility nationwide is -25%; which is a consequence of increased loading of atmospheric PM, and is found to be dependent upon relative humidity. Within tropospheric chemistry, HONO is an important source of OH radicals, and daytime HONO sources are poorly constrained. This work explores the abundance of HONO during a solar eclipse as a natural short-term perturbation to atmospheric photochemistry. A chemical kinetic model is employed to predict the concentrations of HONO using different source scenarios. The study provides insights into the variation of HONO with meteorology, traffic emission and other source.
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Nicholson, Shaun. "Cytological and physiological biomarkers in Perna viridis (Linnaeus) (Bivalvia : Mytilidae)." Thesis, Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20792761.
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Piola, Richard Fabio Biological Earth & Environmental Sciences Faculty of Science UNSW. "Differential tolerance of introduced & native marine invertebrates to heavy metal pollution." Publisher:University of New South Wales. Biological, Earth & Environmental Sciences, 2007. http://handle.unsw.edu.au/1959.4/40673.
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In near-shore marine environments, two of the most prevalent anthropogenic disturbances affecting ecosystem diversity and function are the invasion of exotic species, and the release of toxic chemicals. Estuarine and harbour environments worldwide are dually subjected to high levels of toxic disturbance and ever increasing rates of invasion, via activities such as boating and shipping. It is not clear, however, whether the success of invasive species is influenced by the presence of toxic contaminants in these impacted environments. In particular, nonindigenous marine species (NIS) may be advantaged in chemically disturbed environments if they are more tolerant of toxicants. This thesis examines whether nonindigenous and native sessile invertebrate species have differential tolerance to a common aquatic contaminant, copper (Cu), which has links to both the invasion process (via its use in antifouling paints and the vector of hull fouling) and the modification of recipient environments (via human-mediated pollution). A series of laboratory- and field-based experiments showed that the cosmopolitan invasive bryozoans Watersipora subtorquata, Bugula neritina and Schizoporella errata are highly tolerant of copper pollution. The larvae and adults of W. subtorquata and B. neritina in particular were able to survive and grow in copper-polluted environments far exceeding most observed real-world levels (< 100 /??g 1-1). These nonindigenous species also showed very strong postexposure recovery. In contrast, the co-occurring native bryozoans Celleporaria nodulosa and Fenestrulina mutabilis demonstrated comparatively low tolerance to copper, with markedly reduced survival and fitness under Cu contaminated conditions, and inferior recovery abilities post-exposure. These findings were further supported by a long-term manipulative field experiment, examining the effect that varying levels of Cu exposure have on the structure and diversity of developing sessile invertebrate assemblages. Cu exposure decreased native species diversity by up to 50%, yet had no effect on NIS numbers. Consequently, in the presence of copper contamination, NIS dominated sessile communities, often resulting in substantial changes to community structure. Important insights were also gained into the nature of metal tolerance in NIS. Toxicity studies on larvae of the introduced bryozoan Bugula neritina revealed intraspecific differences in tolerance to Cu, associated with the level of pollution experienced by the adult source populations. There was also evidence of fitness costs related with increased Cu tolerance. In summary, we have found evidence that the success of invasive species is influenced by chemical contamination. NIS may be advantaged in contaminated estuaries relative to native species and this may assist in their establishment and persistence in new habitats.
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Laopaiboon, Lakkana. "The effect of sublethal and lethal concentration of biocides on the performance and characteristics of rotating biological contactors and the properties of their biofilms." Thesis, University of Hertfordshire, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369763.
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Parsons, Edward Michael. "Hong Kong's Cetaceans: the biology, socioecology and behaviour of Sousa chinensis and Neophocaenaphocaenoides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31236108.
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Gheorghiu, Cristina. "Concentration-dependent effects of waterborne zinc on the interactions between Gyrodactylus turnbulli (Monogenea) and the guppy (Poecilia reticulata)." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102979.
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This research investigated the effects of waterborne zinc (Zn) on the interactions between guppies, Poecilia reticulata (Peters), and Gyrodactylus turnbulli Harris, 1986, a monogenean parasite of its skin and fins. The first objective was to determine if sublethal concentrations of waterborne Zn (up to 240 mug/L added to artificial freshwater) exerted a concentration-dependent effect on the population dynamics of Gyrodactylus on isolated guppies. Whereas survival of uninfected fish was unaffected, mortality of infected fish increased linearly with increasing Zn concentration. In addition, the improved parasite population growth at concentrations up to 120 mug Zn/I suggested either that the elevated Zn promotes survival and/or reproduction of the parasite, or impairs host defense mechanisms. Analysis of lifetime survival and reproduction of individual parasites on and off the fish revealed Zn toxicity to the parasite as survival of detached parasites decreased linearly with increasing Zn concentration and parasite survival on the host was also lower at the highest Zn concentrations. Also, all morphological parameters decreased linearly in response both to increasing concentration and duration of exposure to waterborne Zn. The guppy epidermis responded rapidly to both infection and waterborne Zn, and the cumulative effects of these combined stressors were synergistic for epidermal thickness and mucous cell numbers, but antagonistic in terms of mucin composition. Both Zn and infection induced mucous production, but at elevated Zn concentrations and/or at high parasite burdens, the capacity for continued mucous production was apparently exceeded. I hypothesize that this condition is favorable for parasite survival because of the impaired host response; but unfavorable for host survival because of the high numbers of pathogenic parasites and the inability to control entry of Zn into host tissues. In conclusion, sublethal concentrations of waterborne Zn are more detrimental to the infected host than to the parasite.
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Shirley, Mark David Foster. "The effect of metapopulation structure on evolutionary responses to cadmium pollution in Drosophila melanogaster." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320087.
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Nallani, Gopinath C. "Determination of Bioconcentration Potential of Selected Pharmaceuticals in Fathead Minnow, Pimephales promelas, and Channel Catfish, Ictalurus punctatus." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33189/.
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The primary objective of this work was to determine the tissue-specific bioconcentration factors (BCFs) of the selected pharmaceuticals: norethindrone (NET), ibuprofen (IBU), verapamil (VER), clozapine (CLZ) and fenofibrate (FFB) in two freshwater fishes: fathead minnow and channel catfish. BCF tests on fathead followed the standard OECD 42-day test while a 14-day abridged test design was used in catfish exposures. Additional objectives included a) comparing the measured BCFs to the US EPA's BCFWIN model predicted values, b) comparing the BCF results from the standard and reduced tests, and c) prediction of chronic risk of the pharmaceuticals in fish using the human therapeutic plasma concentrations. Each test included uptake and depuration phases to measure tissue-specific kinetic BCFs. The results indicated that all the pharmaceuticals, except IBU, have the potential for accumulation in fish. Estimated BCFs for NET, VER and FFB may not be significant in view of the current regulatory trigger level (BCF ≥ 2000); however, CLZ's BCF in the liver had approached the criterion level. Significant differences were noticed in the tissue-specific uptake levels of the pharmaceuticals with the following general trend: (liver/kidney) > (gill/brain) > (heart/muscle) > plasma. IBU uptake was highest in the plasma. When compared to the measured BCFs, predicted values for NET, IBU, VER and FFB were slightly overestimated but did not differ largely. However, the measured BCF of CLZ in the liver was approximately two-orders of magnitude higher than the predicted level. The tissue-BCFs for the two species were not widely different indicating the potential usefulness of the reduced BCF test. Comparison of fish and human plasma levels indicated that NET, CLZ and VER have the potential to cause chronic effects in fish.
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Nguyen, Thi Tuyet Nga. "Analysing the effect of industrial and urban polluted zones on microbial diversity in the SaiGon -DongNai river system (Vietnam)." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS582/document.
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Le système fluvial Saigon-Dong Nai (SG- DN) est la plus importante source d'eau pour les douze villes et provinces du sud du Vietnam. Il est aujourd'hui gravement pollué par les activités humaines, agricoles, industrielles et domestiques, constituant une menace pour la vie de millions de personnes. Le ministère vietnamien des Ressources naturelles et de l'environnement a rapporté que les rivières ont reçu environ 1,54 milliard de litres d'eaux usées provenant de 70 parcs industriels par jour, dont 35% de déchets médicaux non traités, et que des tests effectués depuis 2006 ont montré des niveaux élevés de pollution, en particulier de substances toxiques organiques. Jusqu'à présent, il n'y a pas de données sur la diversité microbienne dans le système fluvial SG-DN, en particulier dans les sédiments, où la plus grande partie de la biomasse microbienne est généralement localisée. Les échantillons de sédiments ont été recueillis, réseau hydrographique national SG-DN, à 13 endroits dans les rivières représentant des emplacements pollués. Afin de caractériser les populations microbiennes présentes sur nos sites choisis, l'ADN total des échantillons environnementaux a été extrait et amplifié dans les régions V3 à V1 de l'ADNr 16S. L'étude a révélé que la population microbienne changeait de l'amont vers l'aval au niveau du phylum, du genre et de l'OTU après avoir traversé la zone de population industrielle et dense. De plus, les canaux du bassin versant SG-DN sont fortement pollués par de fortes concentrations de composés organiques (PAH) et possèdent différentes communautés bactériennes par rapport aux échantillons des rivièresThe SaiGon-DongNai (SG-DN)river system is the most important major water source for all twelve Southern Vietnam cities and provinces and is now dramatically polluted by industrial and living activities, giving “a threat” to the lives of millions people sharing this water source. The Ministry of Natural Resources and Environment of Vietnam reported that the rivers received around 1.54 billion liters of waste water from 70 industrial parks per day, including 35 percent of untreated medical waste, and tests since 2006 have found pollution in this river has increased to “serious levels”, an especially high concentration of organic toxic substances. Until now, there is no data on the microbial diversity in SG-DN river system especially in the sediments, where most of the microbial biomass is generally located. The sediment samples were collected in 13 locations across the rivers representing warning polluted locations done by Mr. Nguyen Thanh Hung of the National Water Qualifying in SG-DN river system. In order to characterize the microbial populations present at our chosen sites, the total DNA from the environmental samples were extracted and amplified at the V3 to V1 regions of the 16S rDNA. The study revealed that microbial population changed from upstream to downstream at the phylum, genus and OTUs levels after running through the industrial and dense population zone. Moreover, the canals of the SG-DN river catchment are heavily polluted with high concentrations of organic compounds (PAHs) and possessed different bacterial communities compared to the samples from the rivers
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Lawson, Sarah Louise. "Effect of copper on the gill structure of a euryhaline crab, Carcinus maenas (Crustacea: Decapoda)." Thesis, University of Plymouth, 1994. http://hdl.handle.net/10026.1/2708.
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A posterior gill of the common shore crab Carcinus maenas (Crustacea:Decapoda) was used to study the effects of sublethal copper concentrations on gill morphometry, and gill cell ultrastructure and distribution. Primarily, the ultrastructure and distribution of gill cells in the untreated gill of crabs acclimated to 35‰ seawater were characterised. Gill ultrastructure was subsequently shown to vary markedly at 10‰ compared to 35‰ seawater. Ultrastructural and distributional, rather than gross morphological, change occurred in the gill following exposure to copper at each salinity. Ultrastructural studies showed that as the length of copper exposure increased the gill epithelial layer became highly vacuolated, the number of plasma membrane infoldings and mitochondria became reduced, the microtubular network became disrupted, the endoplasmic reticulum became swollen and the cell cytoplasm contained many free ribosomes. Copper exposure also resulted in an increase in the number of haemocytes in the gill, some of which became attached to the basal epithelial cell surface or actually infiltrated into the epithelial cell cytoplasm. Ultrastructural change was more extensive when copper was administered at 35‰ rather than 10‰ seawater. These effects are described and correlated with previously documented biochemical and physiological responses to heavy metals in crustaceans. In addition, the elemental composition of the gill granular haemocytes suggested they play an important role in the immobilisation and removal of copper-from the gill. This study has shown the way forward in creating a better understanding of the mechanisms behind heavy metal toxicity in marine organisms is the use of environmentally realistic concentrations of heavy metal administered in flow-through seawater systems.
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Sarakinos, Helen C. "The use of chemical analyses, bioassays and benthic biomonitoring in the toxicity assessment of complex industrial effluents." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0019/MQ44271.pdf.
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Bessling, Karen D. "Modeling the potential effects of growth reductions and changes in photosynthetic efficiency and needle retention on the stand-level growth of loblolly pine plantations." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43834.
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An existing individual tree growth and yield model (PT AEDA2) was modified study the potential effects of air pollution stress on the growth and yield of loblolly pine plantations. These modifications were based on the assumption that pollution stress on older trees could result in reductions in diameter and height growth, decreases in photosynthesis, and increased losses of older foliage, as demonstrated in some seedling studies.
One modification applied differential levels of reductions of diameter and height increments to various percentages of trees. Results indicated no sizeable losses on total volume per acre except at severe stress levels (-32 and -64 percent annual diameter and height increments on 50 and 67 percent of the trees).
Another modification consisted of developing a measure of photosynthetic potential to drive diameter and height growth in the model. This new measure was an estimate of foliage weight which was weighted by a factor of photosynthetic efficiency and needle retention for each age class of needles. Reductions of these weighting factors were applied to simulate air pollution stress. Results of this modification show that if air pollution does cause a decrease in photosynthesis and needle retention rates, the impact on over-all stand productivity is minimal. These results are not intended to be quantitative estimates of the effect of air pollution on tree growth but to identify potential areas within an existing growth and yield model where biologically-oriented processes to simulate air pollution impact can be incorporated.Master of Science
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Sze, Wai-chung, and 施慧中. "The effect of chronic copper exposure on the energy budget of two mussels, perna viridis (L.) and septifer virgatus (Wiegmann)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31213613.
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Ren, Cizao. "Evaluation of interactive effects between temperature and air pollution on health outcomes." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16384/.
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A large number of studies have shown that both temperature and air pollution (eg, particulate matter and ozone) are associated with health outcomes. So far, it has received limited attention whether air pollution and temperature interact to affect health outcomes. A few studies have examined interactive effects between temperature and air pollution, but produced conflicting results. This thesis aimed to examine whether air pollution (including ozone and particulate matter) and temperature interacted to affect health outcomes in Brisbane, Australia and 95 large US communities. In order to examine the consistency across different cities and different countries, we used two datasets to examine interactive effects of temperature and air pollution. One dataset was collected in Brisbane City, Australia, during 1996-2000. The dataset included air pollution (PM10, ozone and nitrogen dioxide), weather conditions (minimum temperature, maximum temperature, relative humidity and rainfall) and different health outcomes. Another dataset was collected from the 95 large US communities, which included air pollution (ozone was used in the thesis), weather conditions (maximum temperature and dew point temperature) and mortality (all non-external cause mortality and cardiorespiratory mortality). Firstly, we used three parallel time-series models to examine whether maximum temperature modified PM10 effects on cardiovascular hospital admissions (CHA), respiratory hospital admissions (RHA), cardiovascular emergency visits (CEV), respiratory emergency visits (REV), cardiovascular mortality (CM) and non-external cause mortality (NECM), at lags of 0-2 days in Brisbane. We used a Poisson generalized additive model (GAM) to fit a bivariate model to explore joint response surfaces of both maximum temperature and particulate matter less than 10 μm in diameter (PM10) on individual health outcomes at each lag. Results show that temperature and PM10 interacted to affect different health outcomes at various lags. Then, we separately fitted non-stratification and stratification GAM models to quantify the interactive effects. In the non-stratification model, we examined the interactive effects by including a pointwise product for both temperature and the pollutant. In the stratification model, we categorized temperature into two levels using different cut-offs and then included an interactive term for both pollutant and temperature. Results show that maximum temperature significantly and positively modified the associations of PM10 with RHA, CEV, REV, CM and NECM at various lags, but not for CHA. Then, we used the above Poisson regression models to examine whether PM10 modified the associations of minimum temperature with CHA, RHA, CEV, REV, CM and NECM at lags of 0-2 days. In this part, we categorized PM10 into two levels using the mean as cut-off to fit the stratification model. The results show that PM10 significantly modified the effects of temperature on CHA, RHA, CM and NECM at various lags. The enhanced adverse temperature effects were found at higher levels of PM10, but there was no clear evidence for synergistic effects on CEV and REV at various lags. Three parallel models produced similar results, which strengthened the validity of these findings. Thirdly, we examined whether there were the interactive effects between maximum temperature and ozone on NECM in individual communities between April and October, 1987-2000, using the data of 60 eastern US communities from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS). We divided these communities into two regions (northeast and southeast) according to the NMMAPS study. We first used the bivariate model to examine the joint effects between temperature and ozone on NECM in each community, and then fit a stratification model in each community by categorizing temperature into three levels. After that, we used Bayesian meta-analysis to estimate overall effects across regions and temperature levels from the stratification model. The bivariate model shows that temperature obviously modified ozone effects in most of the northeast communities, but the trend was not obviously in the southeast region. Bayesian meta-analysis shows that in the northeast region, a 10-ppb increment in ozone was associated with 2.2% (95% posterior interval [PI]: 1.2%, 3.1 %), 3.1% (95% PI: 2.2%, 3.8 %) and 6.2 % (95% PI: 4.8%, 7.6 %) increase in mortality for low, moderate and high temperature levels, respectively, while in the southeast region, a 10-ppb increment in ozone was associated with 1.1% (95% PI: -1.1%, 3.2 %), 1.5% (95% PI: 0.2%, 2.8%) and 1.3% (95% PI: -0.3%, 3.0 %) increase in mortality. In addition, we examined whether temperature modified ozone effects on cardiovascular mortality in 95 large US communities between May and October, 1987-2000 using the same models as the above. We divided the communities into 7 regions according to the NMMAPS study (Northeast, Industrial Midwest, Upper Midwest, Northwest, Southeast, Southwest and Southern California). The bivariate model shows that temperature modified ozone effects in most of the communities in the northern regions (Northeast, Industrial Midwest, Upper Midwest, Northwest), but such modification was not obvious in the southern regions (Southeast, Southwest and Southern California). Bayesian meta-analysis shows that temperature significantly modified ozone effects in the Northeast, Industrial Midwest and Northwest regions, but not significant in Upper Midwest, Southeast, Southwest and Southern California. Nationally, temperature marginally positively modified ozone effects on cardiovascular mortality. A 10-ppb increment in ozone was associated with 0.4% (95% posterior interval [PI]: -0.2, 0.9 %), 0.3% (95% PI: -0.3%, 1.0%) and 1.6% (95% PI: 4.8%, 7.6%) increase in mortality for low, moderate and high temperature levels, respectively. The difference of overall effects between high and low temperature levels was 1.3% (95% PI: - 0.4%, 2.9%) in the 95 communities. Finally, we examined whether ozone modified the association between maximum temperature and cardiovascular mortality in 60 large eastern US communities during the warmer days, 1987-2000. The communities were divided into the northeast and southeast regions. We restricted the analyses to the warmer days when temperature was equal to or higher than the median in each community throughout the study period. We fitted a bivariate model to explore the joint effects between temperature and ozone on cardiovascular mortality in individual communities and results show that in general, ozone positively modified the association between temperature and mortality in the northeast region, but such modification was not obvious in the southeast region. Because temperature effects on mortality might partly intermediate by ozone, we divided the dataset into four equal subsets using quartiles as cut-offs. Then, we fitted a parametric model to examine the associations between temperature and mortality across different levels of ozone using the subsets. Results show that the higher the ozone concentrations, the stronger the temperature-mortality associations in the northeast region. However, such a trend was not obvious in the southeast region. Overall, this study found strong evidence that temperature and air pollution interacted to affect health outcomes. PM10 and temperature interacted to affect different health outcomes at various lags in Brisbane, Australia. Temperature and ozone also interacted to affect NECM and CM in US communities and such modification varied considerably across different regions. The symmetric modification between temperature and air pollution was observed in the study. This implies that it is considerably important to evaluate the interactive effect while estimating temperature or air pollution effects and further investigate reasons behind the regional variability.
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Mulowska, Z. "The effect of SOâ†2 on mycorrhizal associations." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239846.
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Shen, Pingping, and 沈萍萍. "Benthic infaunal community at an intertidal mudflat and molecular analysis of the dominant species Neanthes glandicincta (Polychaeta)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40887996.
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Loverde, Laura Elizabeth. "Effect of rate-limited interfacial tension reductions on the displacement of residual NAPLs during surfactant flushing." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19280.
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Al-Khafaju, Adil A. "The fate of fuel oil added to soil and its effect on soil properties." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244880.
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Davies, Cheryl Margaret. "The effect of sunlight and other factors on the survival of starved enteric bacteria in natural waters." Thesis, University of Newcastle Upon Tyne, 1989. http://hdl.handle.net/10443/423.
Full textAbstract:
Results are reported from a series of experiments to determine the effects of certain environmental factors, namely, sunlight, temperature and , salinity on the survival of selected enteric bacteria which are of public health importance either as indicators of faecal pollution or The survival of the as pathogens. starved organisms in seawater and in freshwater microcosms exposed to artificial and natural sunlight, and in the dark, at a range of temperatures was investigated. An acridine orange direct viable count (AODVC) using an epifluorescent microscope was employed in addition to selective and non-selective cultural methods for estimation of decay rates of the test bacteria. The use of the AODVC allowed enumeration of those bacteria which respond to the stresses of the natural environment by entering into a viable but non-culturable form. These otherwise would not be detected, as they are, by definition, non-culturable using traditional enumeration techniques based upon the production of visible signs of growth. Two strategies were employed by the organisms in response to the unfavourable conditions. Prior growth of those members of the Enterobacteriaceae in a nutrient-poor medium before inoculation into the microcosms allowed adaptation of the cells to low nutrient concentrations, thus extending survival and resulting in higher resistance to other stresses such as visible light. This extension was, however, only temporary, the ultimate fate of the bacteria being death. Enterococci were particularly sensitive to low nutrient concentrations and died very rapidly in the light. All bacteria tested were able to adopt the viable but non-culturable strategy in the dark as a temporary measure, though it was only a matter of time before viability as well as culturability was also lost. This included enterococci, for which an AODVC using the antibiotic ciprofloxacin was developed by modifying the original nalidixic acid method. Responses of bacteria in the dark were influenced by temperature. Bright natural sunlight produced rapid death in bacteria exposed in seawater microcosms, a result of the synergistic interaction of salinity, UV light and possibly temperature too, whereas the presence of humic acids in freshwater afforded some protection to the cells by absorbing the damaging UV component of sunlight. Low intensities of UV and visible light typical of those found below the surface of water may induce bacteria to evolve towards a viable but non-culturable form.
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Abedi, Shafa Eddin. "The effect of cadmium pollution on apoptosis in the immune system of carp (Cyprinus carpio)." Thesis, Keele University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397508.
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Liu, Chuang. "Exposure to ambient air pollution and noise in relation to adverse health effect in children." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-173416.
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Adverse health impacts of ambient air pollution and noise have been reported previously. However, many published studies were in adults or aged population, little attention has been paid to children and in particular to noise and the potential combined effect with air pollution. In addition, we considered health parameters, which are underinvestigated so far. In our study, we explored associations between ambient air pollution and noise with blood pressure (BP), and exhaled nitric oxide (eNO) in school-aged children, using data from two German birth cohorts.
Noise levels within a 50m buffer around each participant’s home address were assessed using geographic information system. Exposure estimates of annual average concentrations of air pollution for each participant’s residence were calculated using a land use regression model. Short-term concentrations of air pollution were collected from background monitoring sites. Information on BP and eNO was collected during a physical examination at the 10-year follow-up of the cohorts.
We studied the health impacts of ambient air pollution and noise in children from three different aspects. The association between traffic noise and BP was explored in 605 children, and the results showed that higher minimum levels of weighted day-evening-night noise and nighttime noise around the home residence may increase a child’s BP. Based on this finding, we conducted a second analysis to figure out the combined associations between air pollution and noise with BP, and found that ambient air pollution was not consistently associated with BP with adjustment for noise. Furthermore, the effects of ambient air pollution on eNO were explored within 1985 children, and we observed a significant positive association between short-term, but not long-term, air pollution with childhood eNO.
In conclusion, our study provided more epidemiological evidence on the adverse health impacts of ambient air pollution and noise in school-aged children, and highlighted the confounding association between ambient air pollution and noise. More studies are needed to better assess the combined health effects of ambient air pollution and noise in children.Frühere Studien haben über die gesundheitsschädigende Wirkung von Luftschadstoffen und Lärm berichtet. Allerdings betrachteten viele bislang publizierte Studien Erwachsene oder die ältere Bevölkerung. Kinder und im Speziellen die gesundheitlichen Auswirkungen von Lärm, sowie die gemeinsame Wirkung von Luftschadstoffen und Lärm wurden hingegen bislang nur wenig untersucht. Das ist ein Ziel der vorliegenden Promotionsschrift. Zusätzlich haben wir Gesundheitsgrößen betrachtet, die bisher wenig erforscht wurden. In unserer Studie haben wir die Assoziationen zwischen Luftschadstoffen und Lärmbelastung und Blutdruck und exhaliertem Stickstoffmonoxid (eNO) bei Kindern im Schulalter untersucht. Wir konnten dabei auf Daten von zwei großen deutschen Geburtskohorten zurückgreifen. Die Lärmbelastung innerhalb eines Umkreises von 50m um die Wohnadresse jedes Studienteilnehmers wurde anhand von Lärmpegelkarten im Geographischen Informationssystem modelliert. Schätzungen der mittleren jährlichen Konzentration von Luftschadstoffen an der jeweiligen Wohnadresse wurden anhand von „land use regression“ Modellen berechnet. Kurzzeit-Konzentrationen von Luftschadstoffen wurden mit Hilfe von Hintergrund Monitoring Stationen gesammelt. Informationen zu Blutdruck und eNO wurden während einer körperlichen Untersuchung beim Follow-up der Kohorten im Alter von 10 Jahren gemessen. Wir haben die Auswirkungen von Luftschadstoffexposition und Lärmbelastung auf die Gesundheit von Kindern unter drei verschiedenen Aspekten betrachtet. Der Zusammenhang zwischen Verkehrslärm und Blutdruck wurde bei 605 Kindern untersucht und die Ergebnisse legen nahe, dass ein höherer Mindestpegel des gewichteten Tag-Abend-Nacht Lärmes und des Lärmes während der Nachtzeit um die Wohnung den Blutdruck der Kinder erhöhen könnte. Auf Grund dieser Erkenntnis haben wir eine zweite Auswertung durchgeführt um den gemeinsamen Zusammenhang zwischen Luftschadstoffbelastung und Lärm mit Blutdruck zu untersuchen und haben festgestellt, dass die Luftschadstoffexposition nach einer Adjustierung für Lärm nicht konsistent mit Blutdruck assoziiert war. Darüber hinaus wurden die Auswirkungen der Luftverschmutzung auf das eNO bei 1985 Kindern untersucht. Dabei wurde ein signifikanter, positiver Zusammenhang zwischen Kurzzeit-, jedoch nicht zwischen Langzeitexposition mit Luftschadstoffen und eNO beobachtet. Zusammenfassend lässt sich festhalten, dass unsere Studie weitere epidemiologische Erkenntnisse über die negativen gesundheitlichen Auswirkungen von Luftverschmutzung und Lärm bei Schulkindern geliefert hat. Insbesondere wird damit betont, dass Luftschadstoffe und Lärm wechselseitige Störgrößen in Assoziationen darstellen können. Allerdings sind weitere Studien notwendig, um gesundheitliche Auswirkungen von Luftschadstoffen auf die Knochenumsatzrate bei Kindern abschließend beurteilen zu können.
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Bambridge, Lorraine. "The effect of ozone and ambient pollution on the root and shoot growth of spruce." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239784.
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Outola, Iisa. "Effect of industrial pollution on the behaviour of 239,240Pu, 241Am and 137Cs in forest ecosystems." Helsinki : University of Helsinki, 2001. http://ethesis.helsinki.fi/julkaisut/mat/kemia/vk/outola/.
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Tani, Fahima. "Zinc and copper uptake by wheat and buckwheat under two transpiration rates." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79142.
Full textAbstract:
Wastewater has become a vital new supply for irrigation; however, concerns are mounting about environmental and health hazards related to heavy metals present in wastewater. Experiments were conducted to evaluate wheat ( Triticum aestivum L.) and buckwheat (Fagopyrum esculentum L.) uptake of copper (Cu) and zinc (Zn).Some 15 plants per pot were allowed to establish themselves in the greenhouse for 4 and 6 weeks for buckwheat and wheat, respectively. Plants were then transferred to one of two growth chambers differing in the vapor pressure deficit (VPD), creating conditions for two different transpiration rates to occur: high (HT) and low (LT). A total 48 pots for each crop were seeded in order to evaluate the effect of 8 treatment combinations of Cu and Zn (0/0, 5/0, 15/0, 30/0, 0/25, 5/25, 15/25, 30/25) levels (mg L-1). Treatments were laid out in a completely randomized design within each growth chamber.
Three plants were harvested from each pot at days 10 and 20 for wheat, and days 6, 12 and 18 days for buckwheat to measure dry mass and Cu and Zn content in different plant parts. Heavy metal treatments had no significant effect on transpiration rate for either crops. The higher transpiration rate increased Cu/Zn uptake. A Zn amendment in the absence of Cu had a beneficial effect on buckwheat growth, whereas with Cu at 15 mg Cu L-1 or 30 mg Cu L-1 the lowest dry weights were recorded, regardless of the transpiration rate. Roots contained greater concentrations of Cu and Zn, irrespective of the treatment level and transpiration rate, than did stems, leaves or grain. High retention of heavy metals in the roots of cereal crops may be desirable because these parts are not generally utilized as food or feed.