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1
McClurg, Sarah Elizabeth. "Stream ecosystem response to mitigative limestone treatment in acid impaired, central Appalachian streams". Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3667.
Testo completoAbstract (sommario):
Thesis (M.S.)--West Virginia University, 2004.Title from document title page. Document formatted into pages; contains ix, 104 p. : ill., maps. Includes abstract. Includes bibliographical references (p. 41-49).
2
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.
Testo completo
3
Hoar, Cara Chowning. "Fish response to discharge events from a power plant cooling reservoir in a river affected by acid mine drainage and thermal influences". Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4204.
Testo completoAbstract (sommario):
Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains viii, 70 p. : ill., maps. Vita. Includes abstract. Includes bibliographical references.
4
Horn, Christopher D. "Investigation of the effects of thermal enrichment and acid mine drainage on sensitive aquatic biota in the Stony River, Grant County, WV". Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3948.
Testo completoAbstract (sommario):
Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains vii, 101 p. : ill. (some col.), maps (part col.). Vita. Includes abstract. Includes bibliographical references.
5
Broomall, Phillip A. "Physical and chemical limnological study of an acid mine lake in Sullivan County, Indiana". Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/861393.
Testo completoAbstract (sommario):
Southwestern Indiana has numerous lakes developed in abandoned coal mine spoils which support recreational sports fisheries. Some lakes, due to exposure to acid mine drainage from coal wastes and pyritic spoils, are unsuitable habitats for fisheries development. This study examines a publicly owned acid mine lake with an area of approximately 51 ha, following reclamation and elimination of acid producing areas in its drainage basin. Fifteen physico-chemical sample collections were made over a thirteen month period (1991-1992). Parameters sampled included pH, total acidity, iron, manganese, and aluminum. Comparisons were made to historic pre-reclamation water quality data and to established models of acid mine lake recovery. Due to the local topography and exposure to prevailing winds, the lake was generally well mixed throughout the study. Virtually no summer stratification was found, but typical winter season stratification occurred. The water column was well oxygenated throughout the study. Secchi disk transparency varied from 2.5 m to clear to lake bottom (6 m). This study found no significant change in lake water pH (2.9-3.0 to 3.0-3.2 s.u.) since reclamation activities in 1988. However, changes in total acidity and total metal concentrations had occurred since reclamation which suggested that the lake was in early recovery stages. No trends in water quality improvement were determined which could assist in planning toward the eventual establishment of a sports fishery.Department of Biology
6
Rosfjord, Catherine Harney. "An Evaluation of 20 Year Changes in Chemistry in the EPA Easter Lake Survey, A Statistical Population of Lakes in the Northeastern U.S". Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/RosfjordCH2005.pdf.
Testo completo
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Bernard, David P. "Impact of stream acidification on invertebrates : drift response to in situ experiments augmenting aluminum ion concentrations". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24478.
Testo completoAbstract (sommario):
Recent evidence strongly suggests that aluminum toxicity is important in determining the structural and functional characteristics of freshwater communities affected by acid precipitation. To determine the effect dissolved aluminum has on lotic invertebrates previously unexposed to anthropogenic acidification, experiments were carried out in a second-order headwater stream 50 km east of Vancouver, British Columbia during August 1982. In three separate experiments, HC1 and/or A1C1₃ were added to Mayfly Creek during daylight hours, increasing acidity from pH 6.9 - 7.0 to pH 5.8 - 6.0 and total aluminum from < 0.1 mg/L to > 1.0 mg/L. Biological response was monitored by sampling invertebrate drift with 86 Mm nets.
Relative to an unmanipulated, upstream control site, drift density doubled in response to added H⁺ alone (pH 5.9). When Al₃⁺ was added (pH 5.9) drift density increased fourfold. Following 48 h continuous dosing with HC1 (pH 5.9) there was an even greater response to added Al₃⁺.
Ephemeroptera were able to detect dissolved aluminum and responded almost immediately (within 45 min). Similarly, Trichoptera and Chironomidae detected increased H⁺ concentrations and responded immediately. Response to
augmented Al₃⁺ by Trichoptera, Hydracarina, and Chironomidae was delayed 6 h. However, pre-exposing animals to 48 h HC1 resulted in enhanced aluminum sensitivity for Chironomidae and for Simulium and Plecoptera, which had not responded within 10 h to H⁺ or Al₃⁺ alone. It is proposed that rapid increases in drift density are due to behavioral escape responses, while delayed responses are probably associated with physiological impairment. Evidence was also obtained suggesting that during early stages of morphological development Ephemeroptera and Chironomidae are more sensitive to increased Al₃⁺ and H⁺ concentrations than during later developmental stages.
In laboratory experiments using artificial stream channels, Chironomidae larvae and Ephemeroptera nymphs were exposed to CI⁻ and H⁺ concentrations, equal to those during field experiments. Results showed that drift behavior in these animals is not stimulated by mildly elevated chloride concentrations.
These studies demonstrate that increased dissolved aluminum concentrations intensify biological response to acidification, and confirm acid sensitivity patterns for Ephemeroptera and Chironomidae reported by others. The observed acid
insensitivity of Plecoptera, simuliids, and Trichoptera also conforms to previously described patterns.
Experimentally manipulating this community produced results closely resembling those obtained in similar studies for areas currently affected by acid precipitation. The major difference in results between studies is that invertebrate communities previously unexposed to acidification contain more species sensitive to mild acidification. These latter animals are particularly sensitive to the presence of elevated dissolved aluminum concentrations.Science, Faculty of
Zoology, Department of
Graduate
8
Stendera, Sonja Johnson Richard K. "Spatiotemporal variability of chemistry and biota in boreal surface waters : a multiscale analysis of patterns and processes /". Uppsala : Swedish University of Agricultural Sciences, 2005. http://diss-epsilon.slu.se/archive/00000956/.
Testo completoAbstract (sommario):
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2005.Thesis documentation sheet inserted. Appendix reproduces four papers and manuscripts co-authored with R.K. Johnson. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
9
Dove, Michael Colin Geography Program UNSW. "Effects of estuarine acidification on survival and growth of the Sydney rock oyster Saccostrea glomerata". Awarded by:University of New South Wales. Geography Program, 2003. http://handle.unsw.edu.au/1959.4/20485.
Testo completoAbstract (sommario):
Estuarine acidification, caused by disturbance of acid sulfate soils (ASS), is a recurrent problem in eastern Australia. Affected waters are characterised by low pH and elevated concentrations of metals, principally aluminium and iron. The effects of acid and elevated metal concentrations associated with ASS, on adult Sydney rock oysters, have not been previously investigated. This study tested links between ASS-affected drainage, subsequent estuarine acidification and Sydney rock oyster production problems on the Hastings and Manning Rivers, mid north coast New South Wales. The primary objective of this thesis was to establish if estuarine acidification causes mortality and slow growth in individual Sydney rock oysters by exposing oysters to low pH, iron and aluminium using field and laboratory experiments. Water quality data showed that estuarine acidification was spatially extensive in the Hastings and Manning Rivers following heavy rainfall and was due to mineral acids originating from drained or excavated ASS. Estuarine acidification regularly affected areas used for Sydney rock oyster production following heavy rainfall. Field experiments showed that Sydney rock oyster mortality rates were significantly higher at sites exposed to ASS-affected waters compared to locations that were isolated from ASS-affected waters. Oyster mortality increased with the time of exposure and smaller oysters (mean weight = 5 g) experienced significantly higher mortality relative to larger oysters (mean weight = 29 g). This was caused by acid-induced shell degradation resulting in perforation of the smaller oysters??? under-developed shells. Additionally, Sydney rock oyster growth rates were dramatically reduced at sites exposed to ASS-affected waters and the overall mean condition index of oysters at ASS-affected field sites was significantly lower than the overall mean condition index of oysters at non-impacted sites. Findings from laboratory experiments showed that ASS-affected water alters oyster valve movements and significantly reduces oyster feeding rates at pH 5.5. Acidic treatments (pH 5.1) containing 7.64 mg L-1 of aluminium or ASS-affected water caused changes in the mantle and gill soft tissues following short-term exposure. Degenerative effects described in oysters in this study were also due to iron contained in ASS-affected waters. Iron precipitates accumulated on the shell, gills and mantle and were observed in the stomach, intestine, digestive tubules and rectum. This study concluded that Sydney rock oysters are unable to tolerate acidic conditions caused by ASS outflows and cannot be viably cultivated in acid-prone areas of the estuary.
10
Lonergan, Sean P. "Macroinvertebrate community responses to acidification : isolating the effects of pH from other water chemistry variables". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68205.
Testo completoAbstract (sommario):
The effect of lake acidification was evaluated, in the field, in terms of its impact on both the structural and functional composition of the macrozoobenthic community. The littoral macrozoobenthic community and water chemistry of 45 Canadian Shield lakes was sampled. The water chemistry variables sampled included pH, total dissolved calcium, conductivity, and dissolved organic acid (measured as colour). Partial canonical correlation analysis and partial regression analysis were used to identify those components of the macrozoobenthic community that most directly reflected pH variability. This was done by first removing from the data that portion of the variability attributable to total dissolved calcium, conductivity, and dissolved organic acids. In addition, the spatial structure in the data was removed by identifying the geographic coordinates of the sampling sites.In general, the results presented here are not consistent with previous studies where the response of the macrozoobenthic community was related to pH without consideration of confounding covariables. Snails, leeches, mayflies and crayfish have all been cited for their sensitivity to acidification. The present study found these taxa to reflect, not pH variability, but rather attributes of water hardness. Similar results were found for both total zoobenthic biomass and functional feeding group abundance.
11
Fagbayigbo, Bamidele Oladapo. "Perfluorooctane acid (PFOA) and perfluorooctane sulfonate (PFOS) in the Plankenburg (Stellenbosch) and Diep (Milnerton) Rivers, and potential remediation using vitis vinifera leaf litter". Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2668.
Testo completoAbstract (sommario):
Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2017.This study represents the first monitoring campaign to assess the seasonal trend of nine perfluorinated compounds (PFCs) in surface water and sediment from the Plankenburg and Diep Rivers in the Western Cape, South Africa. An analytical protocol was developed and validated for qualitative and quantitative routine determination of nine perfluorinated compounds (PFCs), in water and sediment samples using Ultra performance liquid chromatography-mass spectrometry quadrupole time of flight (UPLC-QTOF-MS). This method was applied to determine levels of PFOA and PFOS in environmental samples. Samples were collected along the Diep (Milnerton) and Plankenburg (Stellenbosch) Rivers respectively. Samples were pre-treated, cleaned-up and extracted using solid-phase extraction (SPE) procedures with hydrophilic-lipophilic balance (HLB) C-18 cartridges. Seasonal variation and distribution of PFCs in surface water and sediment was also investigated. Levels of PFCs were monitored in four seasons (summer, autumn, winter and spring) to establish their trend in the environment. The removal of PFOA and PFOS from aqueous solutions using agro-waste biomass of Vitis vinifera (grape) leaf litter was also studied. Activated carbons were produced from the biomass and chemical activation achieved with phosphoric acid (H3PO4) and potassium hydroxide (KOH) for the modification of the carbons’ (AC-H3PO4 and AC-KOH respectively). Activated carbons were characterized using Fourier Transform infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Brunauer- Emmett-Teller (BET) in order to understand the removal mechanisms of the contaminants by activated carbons. The effects of solution concentration, pH, adsorbent dosage, contact time, and the temperature were optimized for evaluation of the removal efficiency of the activated carbons. Adsorption isotherm models were used to analyze the equilibrium data obtained and kinetic models were applied to study sorption mechanisms. A fixed bed column study was conducted using: AC-H3PO4 adsorbent. Experimental parameters such as initial concentration of the solution, column bed height, flow rate and initial concentrations of the influent were optimized to establish the best adsorption efficiency parameters of the column system. Breakthrough curve and exhaustion time were predicted using Adam-Bohart, Yoon-Nelson, and Thomas models for the fixed bed column under varying experimental conditions.
12
Dove, Michael Colin. "Effects of estuarine acidification on survival and growth of the Sydney rock oyster Saccostrea glomerata". Connect to this title online, 2003. http://www.library.unsw.edu.au/~thesis/adt-NUN/public/adt-NUN20050125.110005/index.html.
Testo completo
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Agars, Robert C. "Assessment of the potential environmental effects of soluble hydraulic oil on natural waters /". [Richmond, N.S.W.] : Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030409.114931/index.html.
Testo completoAbstract (sommario):
Thesis (M.Sc. (Hons))--University of Western Sydney, 2001."A thesis presented for the Degree of Master of Science (Honours), Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, March 2001." Bibliography: leaves 62-67.
14
Dahl, Joakim. "Detection of human-induced stress in streams : comparison of bioassessment approaches using macroinvertebrates /". Uppsala : Dept. of Environmental Assessment, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s332.pdf.
Testo completo
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Agars, Robert C. "Assessment of the potential environmental effects of soluble hydraulic oil on natural waters". Thesis, [Richmond, N.S.W.] : Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, 2001. http://handle.uws.edu.au:8081/1959.7/249.
Testo completoAbstract (sommario):
A series of physical and chemical analyses were conducted over a fifteen month period to establish the ecological risk, if any, of discharging minewater into aquatic ecosystems. Organic and inorganic analyses were used to determine the extent of contamination of minewater with soluble hydraulic fluids and other contaminant species. Throughout the sampling period the pithead discharge water exhibited a neutral pH and low levels of iron, manganese, zinc and potassium were found. Parallel toxicological and chemical studies identified elevated zinc levels above published toxicity levels for the test species Ceriodaphnia Dubia, but were not confirmed by subsequent study. The presence of organic species in the pit head discharge water was also identified, but the levels were found to be quite variable. Treatment processes involving the detention of the surface minewater and subsequent passage through wetlands exhibited a beneficial effect in reducing pollutant levels prior to disposal. Comparisons of the chemical composition of the minewater discharge with those of local waters were carried out and found to be similar in nature.
16
Coahran, David Alan. "Effects of liming on plankton and young-of-the-year bluegill growth in Flat Top Lake, West Virginia". Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41973.
Testo completoAbstract (sommario):
The responses at three trophic levels (phytoplankton, zooplankton, young-of-the-year bluegill) were compared between a limed and unlimed arm in a moderately fertile, circumneutral reservoir that was sensitive to acidification, but had not yet shown signs of damage. The east arm (25.5 ha) of Flat Top Lake was treated with 28.8 dry metric tonnes of calcite using slurry box technology between July 13-20, 1987. The design was confounded because calcite dissolution products diffused into the unlimed (west) arm after the treatment which made total alkalinity similar between the arms within 1 month. Phytoplankton gross productivity and chlorophyll a was similar between the arms for the pre- and post-treatment samples as well as for the period after the treatment when total alkalinity was relatively higher in the limed arm. Zooplankton biomass was higher in the unlimed than limed arm in the pre-treatment samples but was similar between the arms in the post-treatments samples; however, the changes in zooplankton biomass after treatment in the limed arm could not be attributed to the treatment. Phytoplankton community composition for the common netplankton and nannoplankton was similar between the limed and unlimed arms for the combined pre- and post-treatment samples: however, Gemellicystis spp., Gloeocystis spp., and Dinobryon spp. showed an order of magnitude higher density in the limed relative to the unlimed arm on the initial post-treatment sample. This difference, as well as the observed post-treatment differences in zooplankton community composition between the two arms could not be attributed to the treatment because there were minimal impacts on nutrient levels (e.g., CO2, total phosphorus) and zooplankton-phytoplankton interactions. Lake transparency was significantly deeper in the limed arm relative to the unlimed arm for the post-treatment samples; however, a corresponding lower dissolved organic carbon concentration was not measured in the limed arm. Young-of-the-year bluegill (e.g., primarily those 15-20 d old) showed significantly higher growth rates in the unlimed arm during the period when total alkalinity was higher in the limed arm, apparently due to a higher density of suitable pelagic zooplankton in the unlimed arm during this period. In conclusion, no significant positive or negative responses to the treatment were detected because of trophic level interactions. The high pre-treatment pH (7.07), small change in post-treatment pH, low dissolution percentage (8-10%), the inability of the sediment dose to neutralize the acidic sediments and induce phosphorus release, and phosphorus rather than carbon dioxide limited primary productivity were the main factors why no significant post-treatment biological responses were detected.Master of Science
17
Wearing, Catherine Louise. "Changes in fluxes of dissolved organic carbon (DOC) from small catchments in central Scotland". Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/368.
Testo completoAbstract (sommario):
Concentrations of dissolved organic carbon (DOC) measured within water bodies have been increasing on a global scale over the last two decades. Changes in temperature and rainfall have been shown to increase the production and export of DOC from catchments with peat soils in the UK (Freeman et al., 2001). However it is not clear whether increases in DOC concentrations are caused by production increases induced by temperature changes or by a greater incidence of high flows induced by rainfall changes. Increases in both temperature and rainfall have been predicted in Scotland over the next few decades (Kerr et al., 1999) which may further increase current DOC concentrations and exports. The implications of this include both a decrease in water quality and an increase in mobility of metals in upland water bodies. The overall aim of the thesis is to determine if the relationship between dissolved organic carbon (DOC) concentrations and discharge has changed over a 20 year period in small stream catchments in Scotland, in order to better understand the role of hydrology, in driving changes in DOC concentration. To achieve this streams draining two coniferous forest sites and one moorland site were monitored intensively between June 2004 and February 2006. Analysis of the relationship between DOC and discharge, within the catchments, identified the importance of the amount of precipitation falling on the catchment, antecedent precipitation and season, on the concentration of DOC that was measured within the stream. Models were then developed using variables to represent these drivers in terms of both the production (seasonal sine values and 14 day average temperatures) and movement (log of discharge (log Q), days since previous storm event and rising or falling stage) of DOC. In the Ochil Hills catchment, the best predictive model, used 4 hour average discharge and 1 day average 30cm soil temperatures (R2= 0.88). In the Duchray and Elrig catchments, the best predictive models produced used discharge and seasonal sine values; the strength of the model was greater in the Elrig (R2= 0.80) than the Duchray (R2= 0.48) catchment. The strength of the regression models produced highlighted the importance of precipitation in the movement of DOC to the stream and temperature variables representing production in the surrounding catchment. To determine if dissolved organic carbon (DOC) concentrations had changed within the three study catchments, since previous research was conducted at the same sites in the early 1980s and 1990s (Grieve, 1984a; Grieve, 1994), then regression analysis conducted in the previous research was repeated, so changes in the DOC and discharge relationship could be identified. Analysis of the Ochil Hills regression equations identified higher log of discharge and lower temperature and seasonal sine values in the present study (2004-06), when compared to the previous study (1982-83). This suggests that more DOC is now available for movement from the soil, and that the difference between winter and summer DOC production has decreased, potentially because of increasing temperatures. This would explain the limited increase in DOC concentration within the Ochil Hills stream. In the Duchray and Elrig streams, a large increase in DOC was identified at all discharges when all the models produced were compared between the two sampling periods (1989-90 and 2004-06). The increasing trend in DOC concentrations is too large to have been produced by change in temperature alone and it is suggested that the measured reduction in acidic deposition has resulted in the increased DOC concentrations measured in the Duchray and Elrig. The results from this research have identified that concentrations of DOC have increased in Scottish streams over the last 20 years and that the increases in DOC have been induced, potentially by temperature changes in climate. However, changes in temperature are not the only driver of this change as the reduction in acidic deposition is potentially more important, specifically in areas with base poor geology such as the Duchray and Elrig catchments.
18
Sajja, Sarala Kumari. "Microbial Community Structure by Fatty Acid Analysis during Polycyclic Aromatic Hydrocarbon Degradation in River Sediment Augmented with Pleurotus ostreatus". Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1211992408.
Testo completo
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Betton, Catherine. "Nitrate-N levels in British streams and rivers : a countrywide perspective". Thesis, University of Exeter, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277094.
Testo completo
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Onuoha, Anthonia Ezinwanne. "The design of a water quality management system for Nigerian rivers". Thesis, University of Salford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357159.
Testo completo
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Khalfallah, Zakia. "Underwater Wireless Sensor Network Deployment forWater Pollution Monitoring in Rivers". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066680.
Testo completoAbstract (sommario):
L'Internet des objets est un domaine en plein essor, qui a reçu une attention considérable à la fois académique et industrielle. En particulier, les réseaux de capteurs sans fil connectent les objets à Internet via une passerelle. Dans ce contexte, les réseaux de capteurs sous-marins sont un axe de recherche très récent qui joue un rôle clé dans plusieurs applications de surveillance, semblant être primordiales envers l’environnement et la santé humaine. Par conséquent, un déploiement judicieux et efficace des réseaux des capteurs sous-marins s’avère crucial. Dans cette thèse, nous abordons la problématique du déploiement 3D des réseaux de capteurs sous-marins dans une rivière caractérisée par l’irrégularité géographique de l’événement à surveiller. Notre application spécifique concerne la surveillance de la qualité de l’eau dans les rivières. L’instabilité de la qualité de l’eau est à l’origine de la répartition non uniforme de la pollution dans l’environnement 3D sous-marin. Dans cette optique, nous étudions séparément le déploiement 3D des réseaux de capteurs sous-marins pour détecter la pollution issue i) d’une substance chimique liquide et ii) d’un contaminant solide. Ces problèmes de déploiement sont NP-difficile et exigent une optimisation combinatoire judicieuse. Afin de surmonter cette complexité, nous proposons plusieurs heuristiques de déploiement et nous abordons le problème en trois étapes. En premier lieu, notre objectif est la génération de la meilleure topologie des stations géographiques de détection afin d’assurer la détection totale de la substance chimique le long de la rivière. Pour cela, nous proposons une première stratégie, BackTracking Field Installation Deployment Algorithm (BT-FIDA), basée sur l’algorithme du Backtracking. Par la suite, nous étudions la meilleure topologie des capteurs chimiques au sein de chaque station de détection. L’objectif est d’assurer une barrière de couverture totale de la substance polluante avec le minimum de coût. La solution est obtenue grâce à notre deuxième proposition, 2D-Underwater Barrier Deployment Algorithm (2D-UBDA), basée sur une optimisation non-linéaire et mixte. Enfin, on s’intéresse à la détection d’un polluant de type solide pour garantir la qualité de surveillance et la connectivité du réseau tout en minimisant le coût de déploiement. Pour cela, nous proposons une nouvelle heuristique de déploiement, 3D-UWSN-Deploy, basée sur la répartition cubique du volume surveillé et l’optimisation linéaire et mixte. Les résultats obtenus confirment une performance satisfaisante de nos algorithmes par rapport à la littératureThe Internet of Things (IoT) is a booming field that has received considerable attention from both academy and industry. In particular, wireless sensor networks are connecting things to the Internet through a gateway. In this context, Underwater Wireless Sensors Network (UWSN) is a very recent network topic which is playing a key role in several sensing application, seeming to be mandatory towards environment and human health. Thus, suitable deployment of underwater sensors for efficient monitoring is a crucial task. In this thesis, we address the issue of deploying an underwater sensor network in a 3D area characterized by the geographical irregularity of the sensed event. Our specific application context regards the water river monitoring. The irregularity of water quality in river comes from the unsteady repartition of pollution within the 3D water environment. In this context, we separately study the 3D underwater sensor deployment problem to detect water pollution issued from i) chemical liquid and ii) solid wastes. The deployment problems require combinatorial optimization and are NP-hard. To overcome the great complexity involved, we propose several heuristic deployment strategies and we tackle the problem in three stages. In the first stage, our objective is to generate the best deployment of geographical Field Installations (FIs) to ensure the full detection of chemical pollutant along the river. An FI can be seen as a virtual wall able to detect the moving pollutant chemical substance over it. For this, we propose a novel backtracking-based deployment strategy named BackTracking Field Installation Deployment Algorithm (BT-FIDA) which minimizes the number of FIs while ensuring full coverage of the river. In the second stage, we aim to find the best topology of chemical sensors inside an FI in order to form a barrier detection of the polluting substance with the minimum deployment cost. This is performed thanks to our second proposal based on a mixed integer optimization namely 2D Underwater Barrier Deployment Algorithm (2D-UBDA). Finally, in the third stage, we move to the detection of a solid pollutant within an FI. Our objective is to minimize the number of deployed underwater sensors while ensuring i) the required Quality of Monitoring (QoM) (i.e., differentiated probabilistic detection) and ii) wireless network connectivity. To generate the best topology, we propose a novel deployment heuristic, named 3D-UWSN-Deploy, based on a sub-cube tessellation of the monitored FI and a mixed integer linear program optimization. Simulation results show that our contributions outperform the related deployment strategies
22
Khalfallah, Zakia. "Underwater Wireless Sensor Network Deployment forWater Pollution Monitoring in Rivers". Electronic Thesis or Diss., Paris 6, 2015. http://www.theses.fr/2015PA066680.
Testo completoAbstract (sommario):
L'Internet des objets est un domaine en plein essor, qui a reçu une attention considérable à la fois académique et industrielle. En particulier, les réseaux de capteurs sans fil connectent les objets à Internet via une passerelle. Dans ce contexte, les réseaux de capteurs sous-marins sont un axe de recherche très récent qui joue un rôle clé dans plusieurs applications de surveillance, semblant être primordiales envers l’environnement et la santé humaine. Par conséquent, un déploiement judicieux et efficace des réseaux des capteurs sous-marins s’avère crucial. Dans cette thèse, nous abordons la problématique du déploiement 3D des réseaux de capteurs sous-marins dans une rivière caractérisée par l’irrégularité géographique de l’événement à surveiller. Notre application spécifique concerne la surveillance de la qualité de l’eau dans les rivières. L’instabilité de la qualité de l’eau est à l’origine de la répartition non uniforme de la pollution dans l’environnement 3D sous-marin. Dans cette optique, nous étudions séparément le déploiement 3D des réseaux de capteurs sous-marins pour détecter la pollution issue i) d’une substance chimique liquide et ii) d’un contaminant solide. Ces problèmes de déploiement sont NP-difficile et exigent une optimisation combinatoire judicieuse. Afin de surmonter cette complexité, nous proposons plusieurs heuristiques de déploiement et nous abordons le problème en trois étapes. En premier lieu, notre objectif est la génération de la meilleure topologie des stations géographiques de détection afin d’assurer la détection totale de la substance chimique le long de la rivière. Pour cela, nous proposons une première stratégie, BackTracking Field Installation Deployment Algorithm (BT-FIDA), basée sur l’algorithme du Backtracking. Par la suite, nous étudions la meilleure topologie des capteurs chimiques au sein de chaque station de détection. L’objectif est d’assurer une barrière de couverture totale de la substance polluante avec le minimum de coût. La solution est obtenue grâce à notre deuxième proposition, 2D-Underwater Barrier Deployment Algorithm (2D-UBDA), basée sur une optimisation non-linéaire et mixte. Enfin, on s’intéresse à la détection d’un polluant de type solide pour garantir la qualité de surveillance et la connectivité du réseau tout en minimisant le coût de déploiement. Pour cela, nous proposons une nouvelle heuristique de déploiement, 3D-UWSN-Deploy, basée sur la répartition cubique du volume surveillé et l’optimisation linéaire et mixte. Les résultats obtenus confirment une performance satisfaisante de nos algorithmes par rapport à la littératureThe Internet of Things (IoT) is a booming field that has received considerable attention from both academy and industry. In particular, wireless sensor networks are connecting things to the Internet through a gateway. In this context, Underwater Wireless Sensors Network (UWSN) is a very recent network topic which is playing a key role in several sensing application, seeming to be mandatory towards environment and human health. Thus, suitable deployment of underwater sensors for efficient monitoring is a crucial task. In this thesis, we address the issue of deploying an underwater sensor network in a 3D area characterized by the geographical irregularity of the sensed event. Our specific application context regards the water river monitoring. The irregularity of water quality in river comes from the unsteady repartition of pollution within the 3D water environment. In this context, we separately study the 3D underwater sensor deployment problem to detect water pollution issued from i) chemical liquid and ii) solid wastes. The deployment problems require combinatorial optimization and are NP-hard. To overcome the great complexity involved, we propose several heuristic deployment strategies and we tackle the problem in three stages. In the first stage, our objective is to generate the best deployment of geographical Field Installations (FIs) to ensure the full detection of chemical pollutant along the river. An FI can be seen as a virtual wall able to detect the moving pollutant chemical substance over it. For this, we propose a novel backtracking-based deployment strategy named BackTracking Field Installation Deployment Algorithm (BT-FIDA) which minimizes the number of FIs while ensuring full coverage of the river. In the second stage, we aim to find the best topology of chemical sensors inside an FI in order to form a barrier detection of the polluting substance with the minimum deployment cost. This is performed thanks to our second proposal based on a mixed integer optimization namely 2D Underwater Barrier Deployment Algorithm (2D-UBDA). Finally, in the third stage, we move to the detection of a solid pollutant within an FI. Our objective is to minimize the number of deployed underwater sensors while ensuring i) the required Quality of Monitoring (QoM) (i.e., differentiated probabilistic detection) and ii) wireless network connectivity. To generate the best topology, we propose a novel deployment heuristic, named 3D-UWSN-Deploy, based on a sub-cube tessellation of the monitored FI and a mixed integer linear program optimization. Simulation results show that our contributions outperform the related deployment strategies
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Althaus, Martin. "Dissolved trace metals in the estuarine plumes of the Humber, Thames and Rhine rivers". Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316029.
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Baxter, Helen Abigail. "Framework for remediation of rivers impacted by legacy metal mine pollution". Thesis, University of Hull, 2015. http://hydra.hull.ac.uk/resources/hull:13221.
Testo completoAbstract (sommario):
Seven percent of surface waters in England and Wales are impacted by pollution from abandoned non-ferrous metal mines. It is estimated that there are about five thousand five hundred of these. There is no legal liability to any party attached to abandoned metal mines in the UK if they ceased operation before 1999. Preventing pollution from entering river catchments from these sources can be expensive and public funds are limited in extent. These enduring sources of pollution are a significant impediment to compliance with the legislative requirements, such as the European Water Framework Directive. This thesis develops a framework for integrating pre-existing tools and methodologies to address this environmental problem: Environmental Impact Assessment (EIA), Life Cycle Impact Assessment (LCIA) and Payments for Ecosystem Services (PES). By fully quantifying the economic, social and environmental impacts of abandoned mine discharges and the net benefits of potential management interventions over different scales, it is proposed that the framework can provide a sustainable way forward for identifying appropriate cost-effective remedial interventions, identify sources of funding for remediation to take place through PES, while at the same time being sensitive to stakeholder concerns. To determine the effectiveness of this framework two phases of research have been undertaken. The first was a series of interviews with a range of key stakeholders with relevant knowledge and expertise, targeting key concerns and conflicts that arise in managing legacy pollution. The second was to apply the framework to a specific mine-impacted catchment to determine the effectiveness of the framework and an optimal solution for that site. Key findings of stakeholder interviews revealed the general positive attitude towards PES-schemes also discrepancies in knowledge between different sectors. Industrial representatives emphasised the likely need for regulation to initiate such processes. The potentially important role of stewardship and conservation organisations as “ethical brokers” for such schemes was highlighted, given their expertise at communicating and managing a range of stakeholder opinions. The application of the framework to the Hebden Beck catchment in North Yorkshire found that multiple small scale passive remediation at affected locations would be an optimal solution. The full costs of such systems are outweighed by the potential ecosystem service benefits of metal removal from upland streams. Fundamental to the acceptability and sustainability of the remedial solution was the requirement for habitat offsetting to be incorporated into the proposed works.
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Ibanga, A. J. "The ecotoxicology of waste oils in some Nigerian rivers". Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381825.
Testo completo
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Pham, Huynh Anh. "The dynamics of microbial ferric and sulfate reduction in acidic mine lake sediments and their impact on water quality". University of Western Australia. School of Environmental Systems Engineering, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0004.
Testo completoAbstract (sommario):
[Truncated abstract] Acidic mine lakes are formed as a result of the oxidation and dissolution of metal sulfide minerals and are primarily characterized by low pH values of 2 4. Many strategies for the bioremediation of acidic mine lakes depend on the alkalinity generation capabilities of microbial ferric and/or sulfate reducing bacteria. However nearly all mine lakes are oligotrophic, with very low concentrations of available organic carbon and nutrients; all required for healthy microbial growth. There is also an unusual class of mine lakes characterized by low concentrations of organic carbon and also very low concentrations of dissolved iron and sulfate. Our ability to promote microbial activity in these systems is especially challenging. This study focuses on one of these systems, Lake Kepwari, a coal mine lake in Western Australia. Numerical modeling of remediation strategies is an efficient way of testing scenarios prior to expensive in-field trials. However such modeling relies on good descriptions of microbial processes, including kinetic parameterizations of ferric and sulfate reduction. There has been little research to date on the study of kinetic parameterizations of the chemical and biological alkalinity generation in acidic mine lakes. The objectives of this thesis were to investigate the viability of microbial ferric and sulfate reduction in an ultraoligotrophic, acidic mine lake, to assess the impact of these microbial processes on water quality and to parameterize the Dual Monod kinetics of neutralization under dual limitation conditions. Molecular analyses including most probable number, DNA extraction, polymerase chain reaction, polymerase chain reaction denaturing gradient gel electrophoresis were used to examine the microbial communities in the lake sediments. ... The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and ferric, and as determined in batch experiments, were 0.07 ± 0.01 and 0.048 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants and were 14.37 and 5.6 mmol L-1. The Monod maximum consumption rates under ferric and OC limitation were also estimated. The Monod maximum specific microbial growth rates with respect to dissolved organic carbon and sulfate, , and were 0.05 ± 0.01, 0.08 ± 0.01 and 0.07 ± 0.02 day-1, respectively, and their corresponding Monod half saturation constants, and were 75.5, 131.8 and 10.2 mmol L-1. The Monod maximum consumption rates under sulfate and OC limitation were also estimated. The results of this study suggest that strategies for the remediation of ultraoligotrophic, acidic mine lakes may rely on microbial ferric and sulfate reduction, however additions of both organic carbon and sulfate/ferric are essential. These results can be immediately applied to mesocosm studies in outdoor enclosures and to the management of acidic mine lakes. Furthermore, this thesis has provided a new, valuable understanding on the Dual Monod kinetic parameterizations of neutralization for an ultraoligotrophic, acidic mine lake environment. These parameterizations are essential for the lake ecological models that will be used to investigate remediation scenarios for acidic mine lakes.
27
Walklett, Hilary James. "The pollution of the rivers of South-East Lancashire by industrial waste between c1860 and c1900". Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335084.
Testo completo
28
Villamizar, Velez Martha Lucia. "Modelling non-point source pollution of rivers in the UK and Colombia". Thesis, University of York, 2014. http://etheses.whiterose.ac.uk/7768/.
Testo completoAbstract (sommario):
Mathematical fate models have been developed and validated to simulate the transport of contaminants in temperate regions but little is known about their applicability in the tropics. Different models were applied to simulate brominated flame retardants in Colombia and the UK and to identify differences in model application and drivers of emissions in both regions. Emissions of decabromodiphenyl ether (decaBDE) in Colombia and the UK were estimated and suggested large releases to wastewater textile back-coating and waste management stages. Emission data were used to study the partitioning of the flame retardant with a fugacity approach. Fugacity results from Colombia were in agreement with sediment concentrations from the literature for the outlet of the River Magdalena. GREAT-ER was also applied to simulate decaBDE emissions in the Calder catchment; the model showed good potential for the simulation of the flame retardant. Monitoring of polybrominated diphenyl ethers (PBDEs) in sediments in the Calder showed that decaBDE represented the vast majority of PBDEs analysed (>90%) with increasing concentrations moving downstream. A modelling framework with field-scale models using MACRO was developed to simulate transport of six contrasting herbicides targeted by a management programme in the Wensum catchment in eastern England. The catchment-scale model SPIDER was also used for comparison. Preferential flow was the main driver of pesticide transport to water. A fairly good simulation of the flow was achieved (model efficiency, E = 0.6 for MACRO and 0.4 for SPIDER) but variability in pesticide simulations was observed due to uncertainties in input parameters. In-stream processes had little effect on pesticide simulations from either model. Modelling showed that most of the observed reductions in pesticide transport to the river (ca. 80% decrease between 2006 and 2011) can be explained by changes in weather and flow in the catchment during the study period, but an influence on management practices cannot be excluded. AnnAGNPs was applied to simulate triazine loss to the River Cauca from sugarcane, maize and sorghum in the Cauca Valley of Colombia. Runoff was the main driver of pesticide emissions to water. Satisfactory simulation and validation of the hydrology was achieved after little calibration (E = 0.7). A fairly good simulation of pesticides was generally achieved, but some patterns in the measured data could not be simulated. Use of grab samples resulted in uncertainty in measured concentrations. Implementing best management practices was predicted to result in a 78% reduction in triazine losses, whilst replacing triazine herbicides resulted in an 87% reduction when expressed as a proportion of the total pesticide applied. Uncertainty analyses of sensitive input parameters were carried out for the applied models. Their impact on simulations was chemical- and situation-specific. Recommendations for future research are provided to improve modelling of chemical fate in contrasting situations.
29
De, Jimenez Juana Ramos. "Determination of some acid herbicides in soils". Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279758.
Testo completo
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Guganesharajah, Ramalingam Kandiah. "Development of computational hydraulic and water quality models for rivers, estuaries, reservoirs and aquifers with particular reference to waste stabilisation ponds". Thesis, University of Surrey, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365200.
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31
Bradley, Karen A. "Unfinished business : Missouri's Natural Streams campaign and the changing conditions of environmental action/research /". free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9841206.
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Dodge, Kathryn. "Biodegradation of salicylic acid by natural and recombinant bacteria". Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272736.
Testo completo
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Lake, Bjorn Anders. "The Use of Semipermeable Membrane Devices (SPMDS) for Monitoring Dioxin Levels in Maine Rivers". Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/LakeBA2003.pdf.
Testo completo
34
Baker, Alexander Roberts. "Proton and metal ion interactions of fulvic acid solution and of alumina and alumina/fulvic acid suspensions". Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314936.
Testo completo
35
Perry, Lynsey. "Acid washing of granular activated carbon and its impact on drinking water quality". Thesis, University of Wolverhampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288935.
Testo completo
36
Brierley, Euan. "Nitrogen transformations in an acid forest soil". Thesis, University of Reading, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329579.
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Harlay, Jérôme. "Biogeochemical study of coccolithophorid blooms in the context of climate change". Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210352.
Testo completoAbstract (sommario):
Coccolithophores are unicellular microscopic algae (Haptophyta) surrounded by calcium carbonate plates that are produced during their life cycle. These species, whose contemporary contributor is Emiliania huxleyi, are mainly found in the sub-polar and temperate oceans, where they produce huge blooms visible from space. Coccolithophores are sensitive to ocean acidification that results from the ongoing accumulation of anthropogenic carbon dioxide (CO2) in the atmosphere. The response of these organisms to global change appears to be related to the reduction of their ability to produce calcium carbonate at the cellular level. At the community levels, one anticipates changes in the carbon fluxes associated to their blooms as calcification is reduced. However, the consequences of such environmental changes on this species are speculative and require improvements in the description of the mechanisms controlling the organic and inorganic carbon production and export.The first aspect of this work was to study the response of these organisms to artificially modified CO2 concentrations representative of the conditions occurring in the past (glacial) and those expected by the end of the century (2100). Two different levels were examined: the continuous monospecific cultures (chemostats) allowed us to work at the cellular level while the mesocosms gave light to the mechanisms taking place in an isolated fraction of the natural community. The second aspect of this work consisted of field studies carried out during four cruises (2002, 2003, 2004 and 2006) in the northern Bay of Biscay, where the occurrence of E. huxleyi blooms were observed in late spring and early summer. We describe the vertical profiles of biogeochemical variables (nutrients, chlorophyll-a, dissolved inorganic chemistry, particulate carbon, transparent exopolymer particles (TEP)) and study processes such as primary production, calcification and bacterial production. The properties of these blooms are compared with those reported in the literature and enriched with original measurements such as the abundance and concentration of TEP that could play an important role in carbon export to the deep ocean, modifying the properties of the settling ballasted aggregates.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Hernandez, Juan Pablo. "Nonylphenol activates the constitutive androstane receptor and causes sexually dimorphic changes in P450 expression". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Testo completo
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Lamorde, Umar Abdullahi. "A geochemical study of the origins of biodegraded oils and seeps from Nigeria, Ghana and Scotland". Thesis, University of Aberdeen, 2012. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186760.
Testo completoAbstract (sommario):
Subsurface oil and surface seep samples from the Niger Delta Nigeria, Tano and Cape Three Points Basins in Ghana, and the Orcadian Basin in Scotland were analysed using an organic geochemistry approach. Source organofacies, oil thermal maturity and the effect of alteration processes were evaluated, with the aim of developing a better understanding of the origin, nature and type of petroleum present. Biomarker analyses suggested that undegraded oils are found with biodegraded oils with a range of levels of biodegradation in the Niger Delta. On the commonly used Peters and Moldowan scale of biodegradation, the samples rank between PM level 0 and 7. The Ghanaian and Scottish oils and seeps showed a range of biodegradation levels between PM level 2 and 7. Biodegradation appeared to be the major control on the composition and physical properties of the oils and seeps from Niger Delta and Ghana while there is evidence that a stage of water washing was important for the Scottish seeps. Key aspects of the biodegradation process were reflected in the variable occurrence of hopanoids and other biomarkers. 25-Norhopanes were detected in all samples biodegraded in subsurface reservoirs but absent in seeps degraded at surface conditions. This was observed for both the Ghanaian and Nigeria samples. The inverse relationship of hopane to 25- norhopanes in the Niger Delta is presented for the first time. This evidence supports the hypothesis that 25-norhopanes are a product of hopane demethylation. Furthermore a pathway for the formation of 25-norhopane from 25-norhopanoic acid by decarboxylation is evidence by nature of the covariation in relative concentration of these compounds. Seeps from Scotland show that only moderate levels of biodegradation (PM 3) have significantly reduced monoaromatic and triaromatic steroids abundances. The most likely cause for this is by water washing at surface conditions. Reservoir temperature and oil charge histories appeared to have had a significant influence on the extent of biodegradation in the Niger Delta. The late migration of oil from deeper hotter subsurface regions to shallow reservoirs accounts for the presence of undegraded oils amidst the biodegraded oils in the Niger Delta.
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Lynde, Stuart R. "Techniques for evaluating power plant discharges using in-situ leaf breakdown and flow-through laboratory sediment bioassays /". This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06102009-063152/.
Testo completo
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Serrano, Balderas Eva Carmina. "Preprocessing and analysis of environmental data : Application to the water quality assessment of Mexican rivers". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS082/document.
Testo completoAbstract (sommario):
Les données acquises lors des surveillances environnementales peuvent être sujettes à différents types d'anomalies (i.e., données incomplètes, inconsistantes, inexactes ou aberrantes). Ces anomalies qui entachent la qualité des données environnementales peuvent avoir de graves conséquences lors de l'interprétation des résultats et l’évaluation des écosystèmes. Le choix des méthodes de prétraitement des données est alors crucial pour la validité des résultats d'analyses statistiques et il est assez mal défini. Pour étudier cette question, la thèse s'est concentrée sur l’acquisition des données et sur les protocoles de prétraitement des données afin de garantir la validité des résultats d'analyse des données, notamment dans le but de recommander la séquence de tâches de prétraitement la plus adaptée. Nous proposons de maîtriser l'intégralité du processus de production des données, de leur collecte sur le terrain et à leur analyse, et dans le cas de l'évaluation de la qualité de l'eau, il s’agit des étapes d'analyse chimique et hydrobiologique des échantillons produisant ainsi les données qui ont été par la suite analysées par un ensemble de méthodes statistiques et de fouille de données. En particulier, les contributions multidisciplinaires de la thèse sont : (1) en chimie de l'eau: une procédure méthodologique permettant de déterminer les quantités de pesticides organochlorés dans des échantillons d'eau collectés sur le terrain en utilisant les techniques SPE–GC-ECD (Solid Phase Extraction - Gas Chromatography - Electron Capture Detector) ; (2) en hydrobiologie : une procédure méthodologique pour évaluer la qualité de l’eau dans quatre rivières Mexicaines en utilisant des indicateurs biologiques basés sur des macroinvertébrés ; (3) en science des données : une méthode pour évaluer et guider le choix des procédures de prétraitement des données produites lors des deux précédentes étapes ainsi que leur analyse ; et enfin, (4) le développement d’un environnement analytique intégré sous la forme d’une application développée en R pour l’analyse statistique des données environnementales en général et l’analyse de la qualité de l’eau en particulier. Enfin, nous avons appliqué nos propositions sur le cas spécifique de l’évaluation de la qualité de l’eau des rivières Mexicaines Tula, Tamazula, Humaya et Culiacan dans le cadre de cette thèse qui a été menée en partie au Mexique et en FranceData obtained from environmental surveys may be prone to have different anomalies (i.e., incomplete, inconsistent, inaccurate or outlying data). These anomalies affect the quality of environmental data and can have considerable consequences when assessing environmental ecosystems. Selection of data preprocessing procedures is crucial to validate the results of statistical analysis however, such selection is badly defined. To address this question, the thesis focused on data acquisition and data preprocessing protocols in order to ensure the validity of the results of data analysis mainly, to recommend the most suitable sequence of preprocessing tasks. We propose to control every step in the data production process, from their collection on the field to their analysis. In the case of water quality assessment, it comes to the steps of chemical and hydrobiological analysis of samples producing data that were subsequently analyzed by a set of statistical and data mining methods. The multidisciplinary contributions of the thesis are: (1) in environmental chemistry: a methodological procedure to determine the content of organochlorine pesticides in water samples using the SPE-GC-ECD (Solid Phase Extraction – Gas Chromatography – Electron Capture Detector) techniques; (2) in hydrobiology: a methodological procedure to assess the quality of water on four Mexican rivers using macroinvertebrates-based biological indices; (3) in data sciences: a method to assess and guide on the selection of preprocessing procedures for data produced from the two previous steps as well as their analysis; and (4) the development of a fully integrated analytics environment in R for statistical analysis of environmental data in general, and for water quality data analytics, in particular. Finally, within the context of this thesis that was developed between Mexico and France, we have applied our methodological approaches on the specific case of water quality assessment of the Mexican rivers Tula, Tamazula, Humaya and Culiacan
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Rogerson, Vicky F. "Multielement chromatographic profiling of environmental pollution". Thesis, Sheffield Hallam University, 1999. http://shura.shu.ac.uk/20293/.
Testo completoAbstract (sommario):
This thesis describes the evaluation of the first commercially available Hewlett Packard gas chromatograph - microwave induced plasma - atomic emission detector (GC-MIP-AED) for application to qualitative and quantitative analysis. The technique was applied to a range of environmentally significant samples. A general introduction to the development of the technique and its suitability for environmental applications is discussed and a number of typical applications are reviewed. A fundamental study of the capabilities of the GC-MIP-AED was undertaken. It became apparent that the manufacturers pre-programmed recipes for the different elemental channels required optimising to eliminate ghost emission signals from other sources such as carbon molecular emission. After the optimisation of these elemental recipes for C, S, N, O, Pb and Cl had been achieved the ability of the instrument to perform multielement heteroatom profiling of a range of pollutants with a high degree of selectivity was established. Samples included oils, leaded and unleaded petrols, and coal pyrolyzates. A critical assessment of the instruments capabilities with respect to these applications and other operational issues is also described. The instruments ability to perform quantitative analysis was then studied highlighting a number of problem areas, such as, variable repeatability and limits of detection, relating to the automatic injection facilities. When the appropriate injection liner and injection technique were used, the limit of detection on all the elemental channels monitored was greatly improved. The study was then extended to utilise the GC-MIP-AED for the multielemental analysis of organomercury, organolead and organotin compounds. The instrumental conditions were optimised for each element individually with respect to instrumental operating parameters, repeatability, limit of detection, linearity of response, and also the chosen extraction and derivatisation technique. All parameters were then optimised for the analysis of organomercury, organolead and organotin compounds within a single chromatographic injection for environmental applications including sediment, fish tissue and water samples. The overall objective of this thesis was to identify and evaluate the multielement capabilities of the analytical technique for qualitative and quantitative application to samples of environmental relevance, in particular simultaneous multielement organometallic speciation.
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Ubilava, Mariam. "Effect of winter storm on water quality and fish toxicity the Duwamish and Nisqually Rivers /". Online pdf file accessible through the World Wide Web, 2007. http://archives.evergreen.edu/masterstheses/Accession86-10MES/Ubilava_M%20MESThesis%202007.pdf.
Testo completo
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Rajele, Molefi Joseph. "A comparison of SAAS and chemical monitoring of the rivers of the Lesotho Highlands Water Project". Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&.
Testo completoAbstract (sommario):
The Lesotho Highlands Development Authority routinely uses the South African Scoring System version 4 (SASS4) in conjunction with water chemistry to monitor water quality of rivers in the Lesotho Highlands Water Project areas. The objective of this study was to test the efficiency of SASS4 in these areas.
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White, Paul Andrew. "Detection, discharge and ecological behaviour of genotoxic organic contaminants in the St. Lawrence and Saguenay rivers". Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40281.
Testo completoAbstract (sommario):
The goal of this thesis was to examine the sources and ecological behaviour of genotoxic organics in the St. Lawrence river system. A rapid and effective version of the SOS Chromotest was developed to accomplish the task of genotoxicity assessment. The method, validated with standard reference materials, is particularly well suited to complex environmental extracts. The endpoint investigated throughout the thesis, SOS genotoxicity, is empirically related to more familiar endpoints such as mutagenicity and carcinogenicity. Analyses of literature data confirmed correlations between SOS genotoxicity and both Ames/Salmonella mutagenicity and animal carcinogenicity. Analyses of industrial and municipal wastewaters revealed that organic and inorganic chemical production facilities, metal refining and founding facilities and petroleum refineries release high potency wastes. Loading values indicate that low potency sources (e.g. municipal wastewater and pulp & paper facilities) often have exceptionally high loadings. A substantial portion (2.3-99.8%) of industrial genotoxins are associated with suspended particulates. Sorption partition efficients (K$ sb{ rm d-genotox}$) indicate that municipal wastewater and pulp & paper facilities release particularly soluble genotoxins. Extracts of suspended particulate matter collected near industrial discharges are direct-acting. Bottom sediment extracts are less potent and usually require S9 metabolic activation. Genotoxicity of both bottom sediment and suspended particulates are empirically related to the genotoxicity of regional industrial emissions. Direct-acting substances in the water column appear to be less stable and may be converted to more stable pro-genotoxic substances present in the bottom sediments. A mass balance of genotoxicity for St. Lawrence surface waters revealed that domestic, rather than industrial sources make the largest contribution to observed genotoxicity. The importance of domestic wastes was confirmed
46
Jürgens, Monika. "Biomonitoring of wild fish to assess chemical pollution in English rivers : an application of a fish tissue archive". Thesis, Lancaster University, 2015. http://eprints.lancs.ac.uk/74992/.
Testo completoAbstract (sommario):
Since 2007 CEH and the Environment Agency are building a Fish Tissue Archive by annually collecting roach (and in 2007/08 also some eels and bleak) from a number of English river sites and storing them long-term at -80°C. This provides a resource for retrospective monitoring of bioaccumulative pollutants in the fish tissue - allowing future scientists to answer questions that cannot yet be answered or are not yet asked. By the end of 2014, 1684 fish had been collected of which 179 have so far been analysed for one or more groups of chemicals: metals, organochlorine pesticides, PCBs and PBDEs. The results from the individual fish were compared to each other as well as to regulatory standards and previously published UK and European data. Some of the results are: With the exception of lead in 3% of analysed individuals, no food standards were exceeded, but the environmental quality standard (EQS) for mercury was exceeded in the majority of samples (111/144) and the very low EQS for PBDEs was greatly exceeded in all samples. Some patterns found were: Mercury and selenium increased with size of the fish and to some extent with the distance of the sampling site from the river source. PBDE concentration correlated well with the modelled concentration of treated sewage at the sampling site A hotspot was found for DDTs (banned in 1981) and to a lesser extent lindane, chlordane and copper. Further investigations revealed that a pesticide factory had been located close to the sampling site for much of the 20th century. This shows how unexpected results can point to previously unknown issues, which warrant further investigation. Compared to previous European data, eels were generally less contaminated with organic pollutants and roach were low in mercury and cadmium, but relatively high in lead.
47
McMahon, Jennifer Nicole. "Heavy metal competition for acid volatile sulfide binding sites in southeastern coastal sediments". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/19134.
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48
Luhar, Ashok Kumar. "Random walk modelling of air pollution dispersion". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387006.
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49
Hur, Jae-Seoun. "Effects of air pollution on Azolla-Anabaena symbiosis". Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359764.
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50
Marsden, Gregory Richard. "Towards a real-time road traffic pollution estimator". Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390260.
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