Dissertations / Theses on the topic 'Tracing pollution'
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Miserendino, Rebecca Adler. "Tracing mercury pollution in aquatic ecosystems| Implications for public health." Thesis, The Johns Hopkins University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3571745.
This dissertation addressed questions pertaining to mercury (Hg) fate and transport in aquatic ecosystems by applying stable Hg isotopes as a tracer. Mercury poses a public health burden worldwide. In parts of the developing world, Hg-use during artisanal and small-scale gold mining (ASGM) is pointed at as the source of elevated Hg in the environment. However, Hg from other sources including soil erosion associated with land cover and land-use change (LCLUC) may also contribute to local Hg pollution.
Stable Hg isotope profiles of sediment cores, surface sediments, and soils from two aquatic ecosystems in Amapá, Brazil, one downstream artisanal gold mining (AGM) and one isolated from AGM were assessed. Although previous studies attributed elevated environmental Hg levels in this area to AGM, stable Hg isotopic evidence suggests elevated Hg downstream of AGM sites is dominantly from erosion of soils due to LCLUC.
In contrast, the impact of Hg-use during small-scale gold mining (SGM) in the Southern Andean Region of Portovelo-Zaruma, Ecuador on Hg in the trans-boundary Puyango-Tumbes River was also investigated. By comparing preliminary isotopic Hg signatures from river sediment along the Puyango-Tumbes to soil and sediment from upstream locations along the Puyango tributaries, we suggest Hg-use during SGM in this region is likely responsible for elevated Hg downstream and into Peru. Technical and policy challenges in measuring and responding to gold mining-related cumulative impacts were also reviewed in the context of Portovelo-Ecuador.
Together, the findings not only answer questions of critical importance to preventing Hg pollution in two of the world's most vulnerable ecosystems but also provide information that can be used to better target interventions to reduce environmental Hg levels and subsequent human exposures. Furthermore, the validation and application of the stable Hg isotope method to trace Hg pollution from ASGM in different aquatic ecosystems represents a critical step to the application of stable Hg isotopes to trace pollution in other complex natural environments and to address public health-related questions.
Koch, Benedikt. "Greening or greenwashing dirty laundry? Tracing sustainability in the Tirupur textile cluster." Thesis, Linköpings universitet, Tema Miljöförändring, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129924.
Coch, Caroline. "Pathways and Transit Time of Meltwater in the Englacial Drainage System of Rabots Glacier, Kebnekaise, Sweden." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116256.
Cui, Qing. "Tracing Copper from society to the aquatic environment : Model development and case studies in Stockholm." Licentiate thesis, Stockholm : Royal Institute of Technology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12049.
Babey, Tristan. "Compartimentation et transfert de contaminants dans les milieux souterrains : interaction entre transport physique, réactivité chimique et activité biologique." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S107/document.
Modelling of contaminant transfer in the subsurface classically relies on a detailed representation of transport processes (groundwater flow controlled by geological structures) coupled to chemical and biological reactivity (immobilization, degradation). Calibration of such detailed models is however often limited by the small amount of available data on the subsurface structures and characteristics. In this thesis, we develop an alternative approach of parsimonious models based on simple graphs of interconnected compartments, taken as generalized multiple interacting continua (MINC) and multiple rate mass transfer (MRMT). We show that this approach is well suited to systems where diffusion-like processes are dominant over advection, like for instance in soils or highly heterogeneous aquifers like fractured aquifers. Homogenization induced by diffusion reduces concentration gradients, speeds up mixing between chemical species and makes residence time distributions excellent proxies for reactivity. Indeed, simplified structures calibrated solely from transit time information prove to provide consistent estimations of non-linear reactivity (e.g. sorption and precipitation/dissolution). Finally, we show how these models can be applied to tracer observations and to biodegradation reactions. Two important advantages of these parsimonious approaches are their facility of development and application. They help identifying the major controls of exchanges between advective and diffusive zones or between inert and reactive zones. They are also amenable to extrapolate reactive processes at larger scale. The use of isotopic fractionation data is proposed to help discriminating between structure-induced effects and reactivity
Ghasemifard, Homa [Verfasser], Annette [Akademischer Betreuer] Menzel, Annette [Gutachter] Menzel, and Jia [Gutachter] Chen. "Tracing atmospheric carbon dioxide: pollution sources and air-mass transport influencing high Alpine areas in Central Europe / Homa Ghasemifard ; Gutachter: Annette Menzel, Jia Chen ; Betreuer: Annette Menzel." München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/1221719505/34.
Araújo, Susana Manso. "Tracking sources of fecal pollution in Berlenga Island." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/9740.
As águas marinhas costeiras são suscetíveis a contaminação fecal, tanto por fontes pontuais, como por fontes difusas, que podem ter contribuições de fontes individuais pertencentes a animais selvagens, animais domésticos e seres humanos. Os inputs de fontes difusas no ambiente são dispersos e esporádicos, o que torna a sua deteção difícil. A distinção entre a contaminação fecal de origem humana e não-humana tem vindo a tornar-se, nos últimos anos, um objetivo global crucial, uma vez que tem impacto na saúde humana e na economia local. Uma vez que a qualidade das águas superficiais é relevante para a saúde pública devido à sua ampla utilização, especialmente em atividades de lazer e consumo de marisco, a avaliação das fontes de poluição fecal primárias torna-se, assim, uma medida prioritária. Apesar da contaminação fecal por animais selvagens ser considerada de baixo risco para a saúde humana quando comparada com a poluição fecal de origem humana, as fezes de animais selvagens podem também transportar microrganismos patogénicos para humanos. Nos últimos anos, um problema de contaminação fecal foi detetado na água da praia da Ilha da Berlenga. No sentido de esclarecer qual a origem desta contaminação surgiu este estudo, tendo como principal objetivo a determinação e identificação da(s) fonte(s) de poluição fecal responsáveis pela contaminação da água detetada na Ilha da Berlenga. Este objetivo foi alcançado utilizando a metodologia de “Microbial Source Tracking”, através de tipagem molecular (BOXPCR) de isolados de Escherichia coli provenientes da água da praia, de fezes de gaivotas e de um efluente de origem humana e da análise dos dendrogramas resultantes. Para além disso, outros aspetos foram analisados, nomeadamente, a abundância relativa, a saturação de amostragem e índices de diversidade. Tendo em conta os dados resultantes do presente estudo, é possível concluir que: (i) as gaivotas podem ser consideradas o principal responsável pela poluição fecal da água praia; (ii) o método de amostragem e a estratégia da análise dos resultados obtidos podem ser considerados eficientes, para este tipo de ambiente e isolados; e (iii) o esforço de amostragem não foi suficiente para atingir toda a diversidade das populações de E. coli durante amostragem permitindo, no entanto, concluir quanto à principal fonte de contaminação fecal neste ambiente.
Coastal marine waters are often susceptible to fecal contamination from a range of point and nonpoint sources, with potential contributions from many individual sources belonging to wildlife, domesticated animals, and humans. These nonpoint source inputs into the environment are dispersed and sporadic, which makes their detection difficult. The distinction between human and non-human fecal contamination is becoming an important worldwide purpose, in light of the impact of fecal pollution on human health and economic affairs. Since quality of surface waters is relevant to public health due its wide use, particularly for recreational activities and seafood consumption, accurate assessment of primary sources of fecal pollution is clearly a priority measure. While fecal contamination from wildlife sources is often believed to present low human health risks compared to sewage, wildlife species are believed to carry human pathogens that may pose a health risk to humans as well. In the last few years a problem of fecal contamination has been detected in the beach of the Berlenga Island. Thus, this study has emerged having as major aim the determination and identification of which sources of fecal pollution are the responsible for the water contamination detected in the Berlenga Island. This aim was achieved using a Microbial Source Tracking methodology through molecular typing (BOX-PCR) of Escherichia coli isolates from contaminated water, seagull feces and a human-derived effluent and analysis of the resulting clustering. In addition, relative abundance, sampling saturation and diversity indices were analyzed. Taking into account the data resulting from the present study, it is possible to conclude that: (i) the seagulls can be considered the main responsible for the fecal pollution of the beach water; (ii) the sampling method and the analysis methodology can be considered efficient to this type of environment and isolates; (iii) the sampling efforts were not enough to achieve all the diversity of the E. coli populations sampled allowing, however, the determination of the dominant source of fecal pollution in this environment.
Bothamy, Nina. "Fractionnement anthropique et naturel des isotopes stables du néodyme (Nd) dans l'environnement." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0295.
With the worldwide growing demand for various applications (new technologies, green energies, etc.), rare earth elements (REEs) are now considered as emerging pollutants. These pollutions are/will be of industrial origin (e.g. industrial wastes), of mining origin, or caused by the inappropriate storage of industrial products (e.g. neodymium (Nd) magnets fragile against corrosion). In this context, this PhD project aims to develop a new tool: the study of the mass-dependent isotopic fractionation of Nd (δNd in ‰). The goals of this work were to i) bring the maximum of information in order to help to identify and trace anthropogenic Nd in the environment, and ii) help the understanding of how plants accumulate REEs, especially the hyperaccumulator Dicranopteris linearis ferns, in order to support the studies about the phytoremediation of polluted areas. The δNd of anthropogenic materials (pure Nd synthetic solutions, Nd2Fe14B industrial magnets; δ148Nd range of 1.45 ‰, literature included) was compared to the signature of natural terrestrial rocks of the literature (δ148Nd range of 0.66 ‰). Our results show that the use together of i) the 143Nd radiogenic isotope (ε143Nd, tracer of sources), ii) the stable Nd isotopic composition of Nd (δNd, tracer of sources and processes) and, iii) the kind of stable Nd isotopic fractionation (kinetic or thermodynamic equilibrium), could allow the distinction of the natural from the anthropogenic Nd, and to trace the anthropogenic Nd in the environment. The measurement of the δNd of 5 D. linearis fern specimens, and of 3 biological standards (lichen, apple leaves and duck weed) allowed discovering that biology can fractionate the stable Nd isotopes. Extreme δ148Nd values are -0.415 ± 0.060 ‰ and -0.011 ± 0.022 ‰ (2σmean), respectively for one of the fern petiole and the duck weed. Three principal results were obtained: i) the δNd fractionation is correlated to the fractionation of the light REEs than the heavy REEs for all the studied samples (ferns, lichen, apple leaves, duck weed and all soil materials); ii) the distribution and transport of Nd (and REEs) in the different parts of ferns are correlated to those of manganese (Mn), suggesting similar transport mechanisms for REEs and Mn, for ferns but also for other plants as apple trees; iii) the degradation of clay minerals, on which REEs are mostly adsorbed in the studied soils, can induce the fractionation of stable Nd isotopes, from natural processes (e.g. biological) or anthropogenic processes (REEs mining acidic extraction)
McKinney, Julie Michelle. "Identifying Sources of Fecal Pollution in the Appomattox River Watershed." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9951.
Master of Science
Huang, Xixi. "Identification of Putative Geographic Sources of Bacterial Pollution in Lake Erie by Molecular Fingerprinting." University of Toledo / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1172507289.
Porter, Kimberly Rae. "Determining Sources of Fecal Pollution in Washington D.C. Waterways." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/36009.
Master of Science
Graves, Alexandria Kristen. "Determining Sources of Fecal Pollution in Water for a Rural Virginia Community." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34409.
Master of Science
Bowman, Amy Marie. "Determining Sources of Fecal Pollution in the Blackwater River Watershed, Franklin County, Virginia." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/34546.
Master of Science
Reeves, Alastair Ian. "Contaminant tracking through dendro-chemical analysis of tree-radii." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69688.
An elemental index was developed to facilitate the use of dendro-chemical analysis in periods of suppressed tree growth resulting from environmental pollution.
Vadde, K. K. "Application of microbial source tracking techniques to characterize fecal pollution entering Taihu Lake (China)." Thesis, University of Liverpool, 2018. http://livrepository.liverpool.ac.uk/3028229/.
AbdelZaher, Amir Mahmoud. "Microbes At A Non-Point Source Sub-Tropical Recreational Marine Beach And Their Implications On Human Health And Beach Monitoring Practices." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/367.
Carratalà, Ripollès Anna. "Contaminació viral del medi ambient: persistència i traçabilitat / Environmental viral pollution: persistence and source tracking." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/111289.
Graves, Alexandria Kristen. "Identifying Sources of Fecal Pollution in Water as Function of Sampling Frequency Under Low and High Stream Flow Conditions." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/27162.
Ph. D.
Lamendella, Regina. "Assessment of Fecal Source Pollution in Plum Creek Watershed, Nebraska Using Bacteroidetes-Targeted PCR Assays and Phylogenetic Analysis." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1141427143.
Lang, Cassandra C., and University of Lethbridge Faculty of Arts and Science. "Identification and metabolic characterization of host-specific enterococci for use in source-tracking faecal contamination." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/265.
xxiii, 264 leaves ; 29 cm.
Morgan, Jake Roberts. "Tracking the little black 'rain' clouds: an enviro-economic analysis of ambient air pollution effects on pediatric asthma." Thesis, Montana State University, 2012. http://etd.lib.montana.edu/etd/2012/morgan/MorganJ0512.pdf.
Dickerson, Jerold W. Jr. "Evaluation, Development and Improvement of Genotypic, Phenotypic and Chemical Microbial Source Tracking Methods and Application to Fecal Pollution at Virginia's Public Beaches." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/28723.
Ph. D.
Coakley, Tricia L. "LOCATING HOT SPOTS OF FECAL POLLUTION IN AN URBAN WATERSHED OF CENTRAL KENTUCKY USING BACTEROIDES 16S rRNA MARKERS." UKnowledge, 2011. http://uknowledge.uky.edu/ees_etds/4.
Hussein, Khwam Reissan. "Source tracking of faecal indicator bacteria of human pathogens in bathing waters : an evaluation and development." Thesis, University of Plymouth, 2014. http://hdl.handle.net/10026.1/3011.
Geary, Phillip M. "On-site system effluent source tracking using geochemical and microbial tracers in a coastal catchment." View thesis, 2004. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20051223.123840/index.html.
Warlimont, Petra. "Application of the Tracking and Analysis Framework (TAF) to Assess the Effects of Acidic Deposition on Recreational Fishing in Maine Lakes." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/WarlimontP2002.pdf.
Limbo, Beulah Sepo. "Insulator aging tests with HVAC and HVDC excitation using the tracking wheel tester." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2529.
ENGLISH ABSTRACT: Limited research results are available on the aging impacts of surface discharges for High Voltage Direct Current (HVDC) excitation on practical insulators using the Tracking Wheel Tester (TWT) methodology. This thesis gives details of an experimental investigation to compare the aging performance of insulator samples using the TWT for High Voltage Alternating Current (HVAC) and positive and negative polarity HVDC excitation. Two series of tests were performed. The first series of tests evaluated the aging of six insulator rods, namely three Room Temperature Vulcanized Silicone Rubber (RTV SR) coated glass samples and three uncoated glass samples. Three creepage distances were used for each of the test materials, namely 277 mm, 346 mm and 433 mm. The tests were conducted with HVAC excitation and the test methodology described in the IEC 61302 standard. The second series of tests involved the testing of actual insulator samples. The test voltage and conductivity of the salt water solution were also adapted. Six insulators from different manufacturers, representing different materials and specific creepage distances, were tested with HVAC and positive and negative polarity HVDC excitation. The test samples consisted of Ethylene Propylene Diene Monomer (EPDM), High Temperature Vulcanized Silicone Rubber (HTV SR), porcelain and SR coated porcelain insulators. The aging performance of the different test samples for the three types of excitation are compared in terms of peak leakage current, visual observations of surface degradation and hydrophobicity properties. The leakage current data for HVAC excitation shows that the insulators from the different manufacturers perform differently, even for the same type of material. The results also indicate differences in the way the surfaces degrade, as well as the rate of degradation. For insulators representing the same specific creepage distance, but different materials, it has been shown that the material does influence the aging performance. Comparison of the leakage current data for the HTV SR insulators from the same manufacturer, but with different specific creepage distances, shows that the specific creepage distance affect the aging performance significantly. In general, the test insulators showed higher peak leakage currents with HVDC excitation compared to HVAC excitation. The results for positive polarity HVDC excitation show that the dry band arcing, as well as the discharges, has the same form for all six insulators. The colour of the dry band discharges ranged from a blue-ish orange to a dark yellow, depending on the intensity of the leakage currents. The hydrophobic insulators, namely the HTV SR, EPDM and RTV SR coated porcelain insulators, had lost hydrophobicity within the first week of testing. The results for negative polarity HVDC excitation show severe surface degradation compared to the results for HVAC excitation. The effect of positive polarity HVDC excitation, however, seems to be more severe in terms of leakage currents and aging compared to negative polarity HVDC excitation.
Hartard, Cédric. "Les bactériophages ARN F-spécifiques comme indicateurs du danger viral lié à la pollution fécale des matrices hydriques et alimentaires." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0152/document.
Enteric viruses are a leading cause of fecal-oral route transmitted diseases and currently, conventional fecal indicator bacteria (i.e. Escherichia coli, enterococcus) fail to assess this kind of hazard. In this context, the use of more efficient indicators to assess the hazard linked to viruses in water or foodstuff is required. F-specific RNA bacteriophages (FRNAPH) present numerous benefits for this purpose. Of enteric origin, these viruses are found in high concentrations in wastewater. Sharing many structural similarities with pathogenic enteric viruses, FRNAPH are easily cultivable and their potential to track the origin of the pollution is also often investigated. However, some limits are still associated with these indicators, regarding to their ability to track the origin of the pollution or concerning the lack of correlation with pathogens. In this context, the aim of this work was to make clear the potential of FRNAPH as fecal and as viral indicators in environmental waters and shellfish. As a first step, their ability to track human pollution was optimized. In addition, our results underlined the gains bringing by FRNAPH detection, especially when focusing on shellfish microbiological quality management. Indeed, unlike fecal indicator bacteria, the accumulation of FRNAPH and their persistence in shellfish have been found to be close to that of enteric viruses (i.e. norovirus). Furthermore, when using comparable methods for their detection, high correlation was observed between human FRNAPH and norovirus in shellfish. Taking into account these observations, a sensitive method allowing the detection of infectious FRNAPH of human origin was developed to improve viral hazard management in water and food commodities (e.g. environmental waters, shellfish, soft fruits, leaf)
Geary, Phillip M. "On-site system effluent source tracking using geochemical and microbial tracers in a coastal catchment." Thesis, View thesis, 2004. http://handle.uws.edu.au:8081/1959.7/566.
Rusiñol, Aràntegui Marta. "Disseminació i traçabilitat de la contaminació viral en conques fluvials = Dissemination and source tracking of viral contamination in river catchments." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/145833.
This thesis was designed to evaluate, through the study of viruses, the source of the fecal contamination and its spread in water matrices. For this purpose molecular tools have been used for the detection and quantification of specific human porcine and bovine viruses, and a new tool has been developed to trace ovine pollution in the environment. Human waterborne viruses pose the main risk to humans, but animal feces, with potential zoonotic pathogens, also represent a risk to human health. The intensification of animal production and the predicted scenarios for climate change, with increase of torrential rains, present new challenges for the control of fecal contamination in water . Much of this work has been linked to the European project VIROCLIME allowing studies conducted worldwide. We characterized the spread of contaminant human viruses in a Mediterranean river basin . By recording hydro-climatic variables, collecting samples of river water, sea water and wastewater, and analysing FIB and human virus indicators of fecal pollution (HAdV and JCPyV), pathogenic viruses (NoVGII , HEV) and an emerging virus (MCPyV) we have studied, thoughouth a year, the impact of raw wastewater and efluents from the wastewater treatment plants the microbiological quality of the river. In a second study, conducted with laboratories in Sweden, Greece, Hungary and Brazil, we standardized the viral concentration method, Skimmed Milk Flocculation, and specific qPCR assays to identify and trace the origin of contamination in water. During an 18 months sampling period, in river basins located in the mediterranean region, arctic, continental and tropical regions, we identified human (HAdV and JCPyV), bovine (BPyV ) and porcine viruses (PAdV), demonstrating that these tools are reliable and useful for any geographic area or water matrix. At the beginning of this thesis, only porcine and bovine viral fecal indicators were available to trace fecal pollution. Since no ovine viral indicator was described before the present work, we designed a study to develop a new tool to trace sheep fecal contamination. Firstly we analyzed urine and stool samples from sheep, with a broad spectrum PCR assay for the detection of polyomavirus. We obtained sequences of a putative new ovine polyomavirus and designed two PCR assays specific for the new ovine virus. During the last year of the thesis raised a stay in New Zealand because it is the country with more sheep per capita and represents much of the livestock industry in the country. Trace and identify the source of animal fecal contamination in water is therefore essential for both waste management for the evaluation of risks to human health. The fourth study included in this thesis was designed to identify the main sources of fecal contamination and evaluate the same time , the different tools used MST in New Zealand and the student laboratory. River samples were collected at major livestock areas south of the island , and analyzed E.coli , viruses specific indicators of human fecal contamination (HAdV, JCPyV) bovine (BPyV) and sheep (OPyV) specific bacterial markers in humans (BacH, BacHum-UCD, BiAdo) and ruminants ( BacR) and sterols and stanols indicators of human fecal contamination or ruminants.
Zhong, Xiao. "A study of several statistical methods for classification with application to microbial source tracking." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0430104-155106/.
Keywords: classification; k-nearest-neighbor (k-n-n); neural networks; linear discriminant analysis (LDA); support vector machines; microbial source tracking (MST); quadratic discriminant analysis (QDA); logistic regression. Includes bibliographical references (p. 59-61).
Symonds, Erin Michelle. "Pepper Mild Mottle Virus as a Surrogate for Enteric Viruses: Implications for Assessing Water Quality." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6590.
Korajkic, Asja. "Discrimination of Human and Non-Human Sources of Pollution in Gulf of Mexico Waters by Microbial Source Tracking Methods and the Investigation of the Influence of Environmental Factors on Escherichia coli Survival." Scholar Commons, 2010. http://scholarcommons.usf.edu/etd/3503.
Roca, Carceller Guillem. "Tracking environmental change in seagrass meadows: understanding indicator behaviour across space and time." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/325415.
Entendre com responen les fanerògames marines a les pressions, és clau per a poder gestionar tant els herbeis com les aigües costaneres. Actualment, disposem d’un gran nombre d’indicadors basats en fanerògames marines. Però, la manca d’informació sobre com responen als canvis ambientals, fa que no sigui fàcil escollir quins indicadors són els més adients per a cada tipus i objectiu de gestió. Aquesta tesi avalua les tres característiques bàsiques de la resposta dels indicadors més utilitzats als canvis ambientals: la robustesa de la resposta, la especificitat dels indicadors a diferents pressions i el temps de resposta. Per analitzar aquestes tres característiques, fem servir diferents aproximacions complementàries. Al capítol 3, analitzem la resposta de diferents indicadors a les obres d’ampliació del port de Blanes, situat just al costat d’un herbei de Posidonia oceanica. Als capítols 4 i 5, estudiem com responen els indicadors a la millora de la qualitat de l’aigua a la costa catalana. Finalment, al capítol 6, presentem una metaanàlisi que estudia com responen els indicadors a diferents factors d’estrès. De totes tres aproximacions, hem pogut comprovar que el nivell d’organització dels indicadors (i.e. bioquímic, estructural) és clau a l’hora de determinar el grau d’especificitat de la resposta dels indicadors a les pressions: generalment, a més baix nivell d’organització (e.g. bioquímic), més específica és la resposta i com més alt (e.g. demogràfic), més ampli és el rang de pressions que un indicador pot detectar. El temps de resposta dels indicadors varia també en funció del nivell d’organització dels indicadors, especialment, quan es tracta de la detecció de millores ambientals. A més a més, la metaanàlisi destaca la importància de la mida de les plantes per determinar el temps de resposta. Les espècies grans triguen més a detectar la degradació de les condicions ambientals i, molt més, a detectar la millora, especialment, si s’utilitzen indicadors estructurals o demogràfics. Basant-nos en els resultats d’aquesta tesi, hem elaborat un esquema per ajudar els gestors a escollir el conjunt d’indicadors que més s’ajusti a cada objectiu de gestió. Utilitzats correctament, aquests indicadors són molt útils per fer el seguiment, tant de l’estat de salut dels herbeis, com de la qualitat del medi.
Douar, Adnane. "Recherche de matériaux isolants pour la conception d'une nouvelle génération de connecteurs électriques haute tension : influence de la pollution sur les phénomènes de décharges partielles du contournement et de claquage." Thesis, Ecully, Ecole centrale de Lyon, 2014. http://www.theses.fr/2014ECDL0046/document.
In the present study, we deal with an essential problem related to electrical lines accessories and more particularly to piercing connectors (TTDC 45501FA) commercialized by a private company named Sicame and which is located in Arnac-Pompadour (Corrèze, France). This product/accessory is designed to provide power diversions on medium voltage live lines HVA operating between 15 and 25kV. However, it becomes required to design a new generation of piercing connectors able to operate on 52kV live lines because of the electrical power demands that are steadily increasing. Actually, the main concerns about these products are the occurrence of partial discharges within the insulating material volume (polyamide 6 containing 50%wt of glass fibers). Most of the time, these discharges induce an early ageing process of the accessory under the combined effects of a corrosive environment (as salt fog) and an electric field threshold. Thus, the main objective of the present Ph.D. thesis is to carry out an appropriate choice of insulating materials among several tested polymers such as thermoplastics and thermosetting epoxy resins and EPDM elastomers that are capable of withstanding several constraints: thermal and electrical and mechanical and chemical conditions. The experimental section is focusing on the measurements of flashover voltage and partial discharges activity propagating on polymeric surfaces and breakdown voltage within material bulks under A.C voltage. That is why polymeric samples with plane surfaces and textured surfaces are molded to compare their resistance to partial discharges when being subjected to polluted environments such as salt fog; these measurements are necessary to choose the suitable materials for the required application to be integrated in the new generation of connectors. Then, the optical and electrical characterization results of creeping discharges propagating on several polymeric surfaces under lightning impulse (L.I.) voltage with its both polarities (positive and negative) and for two kinds of applied electric field (normal and tangential) are presented in the case of solid/air interfaces. Final length measurements of creepage discharges are the main parameter for distinguishing material properties. The whole obtained results (under AC and LI voltages) allow us to point out the cycloaliphatic epoxy resins as potential candidates to the conception of a new generation of piercing connectors. In addition, the electric field simulation and modelling of the TTDC 45501FA connector by using the Flux 2D/3D software seems to be helpful to design a connector prototype which exhibits a new geometry and is able to reach a voltage level that equals 52kV
Greig, Denise J. "Health, disease, mortality and survival in wild and rehabilitated harbor seals (Phoca vitulina) in San Francisco Bay and along the central California coast." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/1885.
Cheng, Yung-Hsuan, and 鄭詠瑄. "Method of Tracing and Regulations for Indoor Air Pollution Sources." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5650004%22.&searchmode=basic.
國立中興大學
通訊工程研究所
107
In recent years, outdoor air pollution is getting more and more serious, and people often close their doors and windows to block dirty air outside. But when we are in a sealed building, it does not certainly means that the indoor air quality will be better. When the indoor ventilation is insufficient, harmful substances in the air are easily to accumulated, and the indoor air quality will deteriorating. Therefore, if the window is closed for outdoor air pollution, it is possible to increase the concentration of harmful gases in the room. Therefore, we use wireless sensor networking (WSN) technology to establish indoor and outdoor sensing nodes and become a smart Internet of things (IOT) system. In this system, indoor and outdoor sensing node consolidate the sensing values, transmit them to the computer database by Lora to stored, and put the data in the deep learning module for predictive control with a set of rules. When the new data is input, the most suitable control method will be predicted according to the current learning state. Accordingly, integrating indoor and outdoor sensed pollution concentrations for analysis and regulation may improve the air quality in our room.
Mu-JenChu and 朱牧人. "Precise Measurement of Cd Isotopes in Sediments for Tracing Environmental Pollution Sources." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/4465fd.
國立成功大學
地球科學系碩博士班
101
Taiwan is a densely populated country with lots of crowded and overused land. The rapidly developing economic growths and industrialization resulted serious heavy metal pollution on agriculture land nearby the factories. Cadmium (Cd) has eight stable isotopic at a mass range from 106 to 116 amu, where a natural isotope fractionation of -0.08~0.05‰/amu was found in various terrestrial samples. Significant isotope fractionation of Cd (-0.28~0.28‰/amu) was detected only during industrial processes at very high temperature, resulting in the lighter nuclides enriched in aerosols and ashes, and heavy nuclides remained in slag. The fractionated Cd isotopic ratios driven by the artificial activities have therefore become specific markers for distinguishing the sources from other naturally available Cd. In this study, we present a high precision Cd isotopic determination method using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS, Neptune) with a combined standard-sample bracketing (SSB) procedures and empirical external normalization (EEN) for mass bias correction during the measurement. A two-stage chemical separation using AG 1-X8 and TRU resin was applied to purify Cd from potential interference elements (Pd, In and Sn). The long term reproducibility of replicated standard measurement was δ114/110CdJMC-SPEX = 0.34±0.08‰ (2S.D., n=18). Significant isobaric interference occurred in some rock samples that containing high amounts of Sn, however it can be corrected successfully by monitoring the 113Cd. The industrial wastes, including effluent water, irrigation water, ground water, sediment, and dust, were systematic processed in this study to further quantify the possible pollution sources and the contamination spreading pathways. Our preliminary result reveals that about 10ppt~1ppb of Cd was found in irrigation water, lower than the EPA’s standard, and about 1~11ppm of Cd in sediments was found. The δ114/110CdJMC value of -0.5‰~0.7‰ and -0.65‰~0.95‰ were determined in irrigation water and sediment, respectively. However, the enrichment factor and geo-accumulation index both shows great pollution of other heavy metals of Hg, Pb, Cr and As, etc. The result of Cd isotope reveals that the main polluted reason for the area surrounds the factory is contributed to the industrial sludge but affected by the atmospheric transport away from the factory. Due to the limited isotopic data available, industrial materials and dusts samples are being processed for clarifying the possibility of Cd contamination on crops and soils. The high precision Cd isotopic determination conducted in this study helps to clarify the extent of Cd isotopic fractionation in local high pollution industries, their possible sources and migration of Cd pollution in natural environment.
Dick, Linda K. "Fecal Bacteroidetes host distributions and environmental source tracking." Thesis, 2004. http://hdl.handle.net/1957/29752.
Graduation date: 2005
Hung-HsiangLi and 李弘翔. "AquaView: An Aquatic-Pollution Detection and Tracking Scheme for Water-Surface Wireless Sensor Networks." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/91127821423154681622.
國立成功大學
電腦與通信工程研究所
98
Spilled invisible pollutions, such as oil or biochemical materials, damage not only the ocean environment but also the regional economics. To prevent such damages from expanding, a wireless sensor network deployed over the ocean, referred to as Water-surface Wireless Sensor Network (WWSN) in this study, is a suitable candidate for timely monitoring of such wide range and continuous moving objects. In WWSN, this study develops an aquatic-pollution detection and tracking scheme, designated as AquaView, based on an autonomous self-localization cluster mechanism. The proposed scheme enables each normal sensor node to automatically discover its location without maintaining the addition information (i.e., the locations of neighboring nodes, a global or a subset of network topology, and so forth) and to efficiently detect and track the boundary of the current moveable pollution in its sensing field. The numerical results obtained using a Qualnet simulator confirm the effectiveness and robustness of the proposed approach.
Chang, Jen-Kai, and 張仁愷. "The Indoor VOC Air Pollution Diffusion Modeling and Source Tracking in Wireless Sensor Network." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/48125722690005417325.
國立中央大學
通訊工程學系
102
Owing to the rising awareness of environment protection and the trend of global warming, more and more people increase awareness of air pollution. Because most of air quality monitoring stations set up in outdoor to monitor pollution and greenhouse gases of metropolitan area, that ignore the importance of indoor air quality (IAQ). However, damage and number of deaths of indoor air pollution are more than outdoors, but sensing device rarely for a long time monitoring. In this study, we focus on volatile organic compounds (VOC) for a long time monitoring in indoor environment. This study uses experimental data to establish indoor Gaussian diffusion model and proposes prediction method to track sources of VOC air pollution. From simulation results of indoor VOC air pollution diffusion and source tracking to verify our proposed method. This system builds on an open architecture for Arduino AVR(Microcontroller) as the main operational unit with ZigBee module (802.15.4) to transit and receive data in wireless sensor network (WSN). The sensing element uses a metal oxide semiconductor sensor element called TGS-2602 via ADC to get measured value.
Hwang, J. "Adaptive sampling of a discrete underwater plume using an autonomous underwater vehicle." Thesis, 2021. https://eprints.utas.edu.au/45872/2/Hwang_whole_thesis_ex_pub_mat.pdf.
Rivera-Torres, Yaritza. "Isolation and identification of the fecal pollution indicators Enterococcus spp. from seagrass Thalassia testudinum at La Parguera, Puerto Rico and the use of Enterococci for microbial source tracking /." 2008. http://grad.uprm.edu/tesis/riveratorres.pdf.
Santos, Maria Inês Laranjeiro Gouveia. "Seabirds as biomonitors of metal contamination and environmental health in the North Atlantic." Master's thesis, 2019. http://hdl.handle.net/10316/87815.
A poluição química por metais é atualmente um problema nos ecossistemas marinhos e os organismos, expostos, podem acumular níveis altos de metais, provenientes de várias fontes antropogénicas. Altas concentrações induzem o stress oxidativo levando a danos fisiológicos que podem ser detetados com biomarcadores específicos. As aves marinhas são bons bioindicadores de qualidade ambiental, fornecendo informações sobre as relações tróficas e qualidade dos recursos. Os objetivos deste estudo foram avaliar a qualidade ambiental do Atlântico Norte, em particular na costa portuguesa e áreas adjacentes, com ênfase na contaminação por metais, e (1) avaliar a contaminação em três espécies de aves marinhas nas respetivas áreas de alimentação, (2) relacionar a ecologia trófica com as concentrações de metais e (3) avaliar o stress oxidativo das aves de acordo com a ecologia trófica e contaminação.Os dados foram recolhidos durante a época de reprodução de 2017 nas Berlengas (costa oeste) e Ria Formosa (costa sul), Portugal.Foram colhidas amostras de sangue e penas de: 28 cagarras Calonectris borealis em dois períodos de reprodução (pré-postura e alimentação das crias) e duas sub-colónias da Ilha da Berlenga (Furado Seco e Melreu) separadas por 800 m; 27 gaivotas-de-patas-amarelas Larus michahellis em duas colónias (Ilhas da Berlenga e Deserta); e 13 gaivotas de Audouin Larus audouinii (Ilha da Deserta). Foi efetuada quantificação de metais (Al, As, Pb, Cd, Cr, Fe, Cu, Mn, Ni, Hg, Se, Ag, Zn) por ICP-MS e avaliação do stress oxidativo usando os testes de danos no DNA, peroxidação lipídica, OXY e d-ROM. Análise de isótopos estáveis (SIA) e dispositivos GPS foram usados para relacionar a contaminação por metais e o stress oxidativo com o comportamento de alimentação das espécies (nicho trófico e uso de habitat).Os resultados revelaram uma clara segregação na contaminação entre as três espécies e entre colónias/sub-colónias. No geral, a gaivota de Audouin e a cagarra foram as espécies mais contaminadas para a maioria dos metais, provavelmente devido à sua dieta composta exclusivamente por peixe e outros recursos marinhos. Por outro lado, a gaivota-de-patas-amarelas apresentou menores níveis de contaminação para a maioria dos metais. Esta espécie alimenta-se regularmente de outras fontes de alimento terrestres para além de peixe, o que pode induzir a menores níveis de contaminação. Curiosamente, observaram-se diferenças significativas na contaminação entre duas sub-colónias de cagarras separadas por apenas 800 m, em alguns metais específicos. Os dados GPS mostram uma segregação espacial parcial entre sub-colónias, suportada por diferenças nos valores de δ13C nas células do sangue, o que pode explicar em parte as diferenças nos padrões de contaminação. No entanto, as aves do Furado Seco reproduzem-se dentro de uma caverna que pode estar exposta a níveis mais altos de alguns metais. Assim, a contaminação pode também estar relacionada com o habitat de reprodução e não apenas com a dieta. Em contraste, as gaivotas-de-patas-amarelas de colónias distantes não mostraram diferenças substanciais na maioria dos metais. No entanto, maiores níveis de Hg na Ilha da Deserta podem estar relacionados com o maior consumo de peixes demersais da pesca de arrasto, enquanto níveis mais altos de Mn e Ni na Ilha da Berlenga podem estar relacionados com o habitat de reprodução.Diferenças no stress oxidativo entre os períodos de reprodução das cagarras foram evidentes. Apesar de diferenças nos valores de δ13C e δ15N do plasma e células do sangue, não foi encontrada nenhuma relação entre os isótopos estáveis e biomarcadores. Estes resultados sugerem que níveis mais altos de stress durante a pré-postura podem estar relacionados com o papel reprodutor das aves. Nas gaivotas, registaram-se diferenças entre espécies e colónias no stress oxidativo, que se relacionaram com o uso de habitat, mas não com a contaminação. Níveis mais altos de stress nas gaivotas-de-patas-amarelas da Berlenga poderão estar relacionados com a exploração de habitats de alimentação mais diversos. Além disso, o controlo populacional de gaivotas-de-patas-amarelas na ilha da Berlenga durante o período de incubação, destruindo ovos, poderá levar a um aumento dos níveis de stress nestas aves. Este estudo sugere também que níveis mais baixos de stress oxidativo da gaivota de Audouin, em comparação com as gaivotas-de-patas-amarelas na Ilha Deserta, podem estar relacionados com a ecologia trófica, mas não com a contaminação.Este estudo permitiu avaliar a qualidade do ambiente no Atlântico Norte e na costa portuguesa. Os níveis de contaminação obtidos foram comparados com outros estudos após uma extensa revisão bibliográfica, mostrando uma maior vulnerabilidade ou exposição das espécies/colónias de estudo para alguns metais (Pb, Cr e Se). Futuros estudos podem ajudar a entender os padrões de distribuição destes contaminantes e respetivas interações tróficas na costa portuguesa
Metal pollution is currently a major issue in marine ecosystems, because organisms are exposed to increasing and accumulating levels from several anthropogenic sources. High concentrations of metals can disturb oxidative balance leading to physiological damages, which can be measured using specific biomarkers. Seabirds are suitable bioindicators of marine environmental health, providing valuable information on trophic relationships and quality of resources. This study aimed to assess environmental health status in the North Atlantic, with emphasis on metal contamination. The main objectives were to: (1) assess contamination in three seabird species within their distinct foraging areas, (2) relate their trophic ecology with respective metal concentrations, and (3) evaluate the oxidative stress of seabirds in relation to their trophic ecology and concentration of metals.Data were collected during the breeding season of 2017 in two distinct areas of Portugal (Berlengas in the west coast and Ria Formosa in the south coast). Blood and feathers were collected from: 28 Cory’s shearwaters Calonectris borealis in two breeding periods (pre-laying and chick-rearing) and two sub-colonies of Berlenga Island (Furado Seaco and Melreu) separated by only 800 m; 27 Yellow-legged gulls Larus michahellis in two colonies (Berlenga and Deserta Islands); and 13 Audouin’s gulls Larus audouinii (only in Deserta Island). Metal quantification (Al, As, Pb, Cd, Cr, Fe, Cu, Mn, Ni, Hg, Se, Ag, Zn) using ICP-MS and oxidative stress assessment using DNA damage, lipid peroxidation, OXY and d-ROM tests were performed. In addition, SIA and GPS data were used to link metal contamination and oxidative stress with the foraging behaviour of each species.Results revealed a clear segregation of metal contamination among the three species and between colonies/sub-colonies. Overall, Audouin’s gull and Cory’s shearwater were the most contaminated species for most metals, presumably because they rely mainly on fish and other marine resources. On the other hand, Yellow-legged gull showed lower contamination levels for most metals. This species feeds regularly on other food sources besides fish, including from terrestrial environments, which may buffer contamination levels. Interestingly, and unexpected, there were significant differences in metal contamination between the two adjacent sub-colonies of Cory’s shearwaters. There was a partial spatial segregation between sub-colonies, supported by differences in δ13C values in red blood cells, which may partly explain such differences in the contamination patterns. However, other potential explanations may be possible, such as the breeding habitat; birds from Furado Seco have their nests inside a long and muddy cave, which can be exposed to higher contamination levels. Thus, contamination might also be related with the breeding habitat itself and not only to foraging habitat. In contrast, Yellow-legged gulls from distant colonies did not show substantial differences in most metal concentrations. However, higher levels of Hg for birds breeding in Deserta could be related with their higher consumption of demersal fish from trawl fisheries, while higher levels of Mn and Ni in Berlenga Island individuals could be related with the respective breeding habitat.Oxidative stress parameters differed significantly between Cory’s shearwaters breeding periods. Despite differences in δ13C and δ15N of plasma and red blood cells, no relationships were found between stable isotopes and biomarkers, suggesting that higher stress levels during pre-laying could be related with intrinsic physiological factors of breeding duties, and not exclusively with birds’ foraging niche. Concerning gulls, differences in oxidative stress between species and colonies were related with birds’ foraging behaviour, but not with metal contamination. Higher stress levels in Yellow-legged gulls from Berlenga Island could probably be related with different exploited environments for foraging. Moreover, a population control of Yellow-legged gulls in Berlenga Island during the incubation period (i.e. egg destroying), may potentially lead to increased stress levels in these birds. This study also suggests that lower oxidative stress levels of Audouin’s gull in comparison with Yellow-legged gulls in Deserta Island, could be related with diet and trophic ecology, but not with metal contamination.This study allowed to assess environmental health in the North Atlantic, particularly along the Portuguese coast and adjacent areas. After comparing contamination levels with an extensive literature review, this study shows a greater vulnerability or exposure of these species/colonies for some specific metals (Pb, Cr and Se). Further studies would help to understand these contaminants’ distribution patterns in seabirds, because very few information exists for the Portuguese coast.
"Novel Colorimetric Sensors with Extended Lifetime for Personal Exposure Monitoring." Doctoral diss., 2019. http://hdl.handle.net/2286/R.I.55643.
Dissertation/Thesis
Doctoral Dissertation Chemistry 2019