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Tesi sul tema "Effects of water pollution on"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 1 febbraio 2022

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1

Bird, Linda Margaret. "The effects of saline pumping water on freshwater invertebrate communities". Thesis, Nottingham Trent University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253693.

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2

Rolph, R. P. G. "The effects of dichlorvos on intertidal communities". Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1316.

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3

Southern, Roger L. "The effects of oil spillages on soil fauna". Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357081.

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4

Hebel, Dagmar Karina. "Effects of copper on gill structure and physiology in Carcinus maenas". Thesis, University of Plymouth, 1997. http://hdl.handle.net/10026.1/2296.

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The effects of sublethal copper exposure at three levels of biological organisation were studied in the common shore crab Carcinus maenas (L.) (Crustacea, Decapoda). The three levels included the ultrastructure of respiratory and osmoregulatory gill tissues; ventilatory physiology (scaphognathite activity); and tissue metallothionein levels. Respiratory gill epithelia were more sensitive to sublethal copper exposure than osmoregulatory gill tissues. The cellular damage observed included severe epithelial necrosis and vacuolation, hyperplasia and haemocyte infiltration. In the respiratory gills, these changes were first present following exposure to 100 µg Cu Lˉ¹ At 500 µg Cu Lˉ¹, there was complete degeneration of the epithelia. In osmoregulatory gills, lipofuscin granules were formed at 300 µg Cu Lˉ¹. Signs of cellular damage (as observed in respiratory gills) appeared in the osmoregulatory gills only following exposure to 500 µg Cu Lˉ¹, and were restricted to areas proximal to the marginal canal. Copper concentrations below 100 µg Cu Lˉ¹ had no effect on gill tissues. This result is discussed with reference to previous studies, and related to inter-population differences and exposure techniques. Gill ultrastructural differences were observed in crabs from two estuaries with different levels of water-borne trace metals, and in crabs transplanted from the cleaner to the more polluted site. Differences included . varying densities of plasmalemmal folds and frequencies of cellular vacuolation, as well as composition and thickness of algal surface layers on the gill cuticle. Following laboratory copper exposures (500 µg Cu Lˉ¹), gill ultrastructural "damage" and tissue metallothionein levels were related to changes in scaphognathite activity. Physiological effects, including changes in scaphognathite rate and periods of apnoea, were exacerbated by increased temperature and hypoxia. Changes in scaphognathite activity and metallothionein levels were not consistent following several exposures to the same level of copper; results are discussed in relation to physiological influences. In contrast, gill ultrastructure showed consistent deterioration following exposure to 500 µg Cu Lˉ¹. Gill ultrastructure represents a reliable indicator of exposure to copper at this concentration compared to both scaphognathite activity and metallothionein concentrations.

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5

Van, Egmond Roger Albert. "The effects of organic pollution on fish detoxification mechanisms and reproduction". Thesis, Edinburgh Napier University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386002.

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6

Amakiri, Jonathan Ombo. "Effects of oil pollution on the saltmarch grass Puccinellia maritima (Huds.) Parl". Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37616.

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7

Berktay, Ali. "The effects of pressure on aerobic biological wastewater treatment using rotating biological contractors". Thesis, Loughborough University, 1993. https://dspace.lboro.ac.uk/2134/11709.

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The aim of this research was to investigate the application and effects of pressure on an aerobic biological wastewater treatment process. For the purpose of the investigation two specially designed, identical, laboratory-scale rotating biological contactor (RBC) units were constructed. One of these was held in a steel pressure vessel while the reference unit was operated open to the atmosphere. The treatment capabilities of the pressurized unit, as compared to those of the reference unit, were determined for a variety of organic loadings at increasing pressures up to a limit of 6 bar. During the investigation, the substrate employed was a synthetic wastewater made up frequently in the laboratory. Most of the analytical work was carried out on composite druly samples of the feed wastewater and of the two effluents produced, both filtered and nonfiltered. In addition, sludge samples from both units were regularly tested for a variety of sludge parameters. The water quality parameters investigated were the 5-day Biochemical Oxygen Demand (BOD5), the Chemical Oxygen Demand (COD), Suspended Solids, pH, Temperature, Ammoniacal Nitrogen and Total Oxidized Nitrogen (TON). The yield of sludge produced and certain characteristics of sludge i.e. Specific Stirred Volume Index (SSVl). Specific Resistance to Filtration, were also obtained. The quantity of air required for the pressurized treatment unit was also investigated. The pressurized treatment unit has demonstrated the capability of operating with a high level of carbonaceous oxidation and nitrification at organic loadings of up to 13 g BOD5/ m2 of disc area per day. In comparison with the identical reference unit operated at atmospheric pressure, the pressurized unit demonstrated slightly improved BODs and COD removal efficiencies, a greatly improved level of nitrification and a substantially lower sludge production. All these characteristics improved with increasing pressure.Of particular importance the sludge yield coefficient was always significantly lower for the pressurized unit than for the reference unit and results such as 0.12 kg dry solids/ kg BOD5 removed at 6 bar pressure are highly signif1cant with regard to the requirements of the modern wastewater treatment industry. Additional investigations were carried out to determine the cost of a proposed full-scale pressurized treatment unit with a design based upon the findings of this investigation. These were compared with the costs of a conventional biological treatment process capable of treating an equivalent wastewater loading. The comparison between the pressurized unit and the selected processes were made for three populations (500, 1,000 and 3,000 persons). The sludge disposal costs of the pressurized unit were appreciably lower than those for the other processes. The results indicated that the cost of the pressurized unit (present value for a twenty-year period) and the costs of activated sludge and conventional RBC processes were found to be similar for the smaller populations. However a substantial saving could be obtained with the pressurized unit for the larger populations. In addition there is an indication that the land requirement of the pressurized treatment unit decreases appreciably as the flow rate increases.

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8

Bruce, Lorna J. "The effects of heavy metal-rich sewage sludge on Collembola communities in grassland". Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266457.

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9

Sanyi, Hassan H. A. R. "Effects of liming of upland soils on nutrient mobilities in relation to water quality". Thesis, University of Aberdeen, 1989. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU020937.

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The work in this thesis relates to understanding the potential effects of using surface liming of upland soils to ameliorate water acidification. Effects on vegetation, soil, and drainage water chemistry are considered. Part I of this thesis reviews the environmental conditions of British Uplands (climate, soils and vegetation), and the relevant literature on water acidification in North-East Scotland. In Part II, each chapter deals with materials, methods used, discussion of the results and conclusion for one of a series of individual experiments. This pattern is followed for a number of laboratory, greenhouse and field studies. Liming of different organic soils significantly increased only the surface layer pH of the soils. The consequence of surface liming should be highly beneficial in terms of water quality, since most of the precipitation in the catchment under consideration (Glendye) during heavy storms, when river acid episodes occur, drains near or over the surface. The effect of lime on pH below the surface should be considered after a year or more. Liming on the other hand increased the mineralisation of organic N and released NH4+ and NO3-. The balance between N mineralization and immobilization by vegetation and microbial biomass should be considered carefully for each individual soil and site. If the mobile NO3- reaches the river or streams and increases the NO3- to beyond an acceptable limit, this could be considered an adverse effect of liming. Although within the timescale of this project there was no adverse effect noticed on the heather under field conditions, the long term effects should be considered carefully in terms of changing vegetation pattern as a result of liming, which will favour growth of grass.

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10

Tan, Lo 1963. "The effects of activated carbon adsorption and ozonation on trihalomethane speciation". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276953.

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Two surface water sources in the southwestern United States, Colorado River Water (CRW) and California State Project Water (SPW), were studied in bench-scale experiments examining two Trihalomethane (THM) precursor removal processes, activated carbon adsorption and ozone oxidation. Both source water contained bromide (Br-) ion leading to brominated THMs upon chlorination. Activated carbon removed THM precursors, as measured by dissolved organic carbon (DOC), while having little effect on bromide. The net result was an increase in the ratio of Br-/DOC and an increase in the relative abundance of brominated THMs. Ozone oxidized higher molecular weight precursor molecules into lower molecular weight by-products which were less reactive with chlorine. Moreover, ozonation transformed Br- to hypobromous acid (an "in-situ" oxidant), leading to an increase in the percentage of brominated THMs.

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11

Dooa, Anita. "The effects of metals on plants in the Avonmouth area with particular reference to Lemna minor". Thesis, Royal Holloway, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336516.

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12

Jobling, Susan. "Environmental oestrogenic chemicals and their effects on sexual development in male rainbow trout (Oncorhynchus mykiss Walbaum)". Thesis, Brunel University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262498.

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13

Pandia, Setiaty. "The effects of detergents in wastewater on foaming at activated sludge plants and on receiving water quality". Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277392.

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14

Kozak, Caroline. "Water quality assessment and its effects on diffuse pollution considering a new water quality and quanttity approach". reponame:Repositório Institucional da UFPR, 2016. http://hdl.handle.net/1884/43629.

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Orientador : Prof. Cristóvão V. S. Fernandes, PhD
Coorientador : Prof. Sérgio M. Braga, D.Sc
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Recursos Hídricos e Ambiental. Defesa: Curitiba, 18/03/2016
Inclui referências : f.165-174
Resumo: Os processos de poluição difusa, assim como as fontes de poluição pontual, podem causar degradação da qualidade da água nos rios. As fontes difusas são abrangentes e de difícil quantificação além de receberem grande influência dos eventos de chuva. Quando a chuva acontece, o escoamento causa lavagem da área superficial, promovendo contribuição de massa poluidora para dentro do rio. Os eventos de chuva são de difícil previsão, induzindo portanto a um interessante problema de monitoramento, que está associado a coleta de amostra para a avaliação da contribuição da massa poluidora dos rios. Portanto, uma alternativa é o uso de amostrador automático, o qual garante que as amostram sejam coletadas durante o evento de chuva, funcionando através de uma interface inteligente, de acordo com as variações da coluna água e seguindo a ascendência e descendência do hidrograma. O objetivo deste estudo é usar a interface inteligente SBN acoplado a um amostrador automático comercial (ISCO) para avaliar a qualidade da água e os efeitos da poluição difusa no Rio Barigui, no ponto de monitoramento denominado BA01, localizado em Almirante Tamandaré/PR. O amostrador inteligente foi instalado junto a uma estação pluviométrica em Almirante Tamandaré, conectado a um sistema de informações datalloger. A amostragem foi programada para cada 5 (cinco) centímetros de variação na coluna d'água, tanto na subida (+ 5 cm) quando na descida (-5 cm) do hidrograma. Após amostragem e o final do evento de chuva, as amostras foram coletadas e levadas para o laboratório para os devidos procedimentos analíticos dos distintos parâmetros de qualidade da água investigados. Os resultados mostram que os parâmetros de qualidade da água tiverem comportamento similar para cada hidrograma específico. A contribuição da massa poluidora para o rio revelou que as concentrações aumentam durante o pico do hidrograma. A análise do evento médio de concentração (EMC) mostrou certa tendência para alguns parâmetros (especificamente turbidez e série de sólidos). A tendência consiste em uma melhor descrição do fenômeno de first-flush, causando aumento da concentração durante o evento, e posteriormente, a diluição devido a assimilação do poluente pelo rio. Curiosamente, diferentes características do evento, como volume de água transportado e vazão máxima, impuseram maiores contribuição de poluição. De forma geral, SBN trabalhou como o esperado, realizando a coleta das amostras seguindo o previsto pelo hidrograma. Foi observado que ocorreu contribuição de massa poluidora devido a fontes difusas no Rio Barigui, no ponto BA01 em Almirante Tamandaré. Entretanto, todo trabalho analítico demandado para quantificar todas as informações para cada evento analisado neste trabalho é significativo. Em termos de gestão de recursos hídricos, planejamento e gerenciamento, esta pesquisa ressalta a necessidade de maiores analises dos potenciais impactos para em todos os instrumentos de gestão estabelecidos pela legislação Brasileira. Mais pesquisas sobre os processos de poluição difusa são necessário para fornecer razoável quantidade de dados, especificamente na integração do uso na calibração de modelos matemáticos de simulação da qualidade da água em rios. Palavras-chave: Fontes não pontuais; Sistema de monitoramento; SBN; Amostrador automático inteligente; Rio Barigui.
Abstract: Diffuse pollution process, as point source pollution, can cause water quality degradation in water bodies. Diffuse pollution sources are extensive and difficult to quantify and, receive strong influence from rainfall events When rainfall happens, the runoff causes superficial area washing-off, promoting pollutant mass contribution into the river. The rainfall events are difficult to predict, therefore inducing an interesting monitoring problem associated to sampling collection for assessment of the contribution of pollutant mass pollutant in rivers. Accordingly, an alternative is the requirement of an automatic sampler, which ensures samples collected during rainfall events, through an intelligent interface, according to variation of water levels, following rising and falling hydrograph. The objective of this study is to use the SBN intelligent interface, connected to an automatic sampler (ISCO), to assess water quality and diffuse pollution effects at Barigui River, in a monitoring site called BA01 located in Almirante Tamandaré. The intelligent sampler was installed to an pluviometric station in Almirante Tamandaré, connected to a datalloger information system. The programming for sample collect was performed for each five centimeters variation in water level, either rising (+ 5 cm) or falling (- 5cm) hydrograph. After sampling and end of the rainfall event, samples were collected and delivered to laboratory to analytical procedures of distinct water quality parameters. The results shows that water quality parameters had a similar behavior to each specific hydrograph. The mass pollution contribution into the river reveals the concentration increasing during hydrograph peak. Event mean concentrations (EMC) analyses showed a trend in some parameters (specially turbidity and solids series). The trend consist in better describing the first-flush increasing concentration during the event, and after, the dilution due assimilation pollutant by the river. Interestingly, distinct events characteristics, as transported volume and maximum flow, impose bigger pollutant contribution. In general, SBN works as expected, performed sampling following hydrograph. It was observed that occurs mass pollutant contribution due diffuse sources at Barigui River, on site BA01 in Almirante Tamandaré. However, all the analytical work demanded to quantify this information is significant for each event analyzed.. In terms of water resources management planning and management, this research highlights the need for more in depth analysis of the potential impacts for all instruments established by the Brazilian legislation. More researches about diffuse pollution process are necessary to provide reasonable data, especially the integration to the use in mathematical models calibration of water quality simulation in rivers. Key-words: Non-point sources; Monitoring system; SBN; Intelligent automatic sampler; Barigui River

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15

Poulton, Madeline June. "Toxic effects of freshwater pollutants on the survival, behaviour and reproduction of Gammarus pulex (L.) and Asellus aquaticus (L.)". Thesis, Cardiff University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320266.

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The toxic effects of cadmium on aspects of the survival, behaviour and reproduction of Gammarus pulex and Asellus aquaticus are described in some detail. Some of the laboratory procedures were validated in field experiments. The presence of the parasites Pomphorhynchus laevis and Echinorhynchu_s1truttae does not modify the toxicity of cadmium (0.01-1.0 mgl ) to their intermediate-Fost G. pu7ex. Pretreatment for 24 hours with 0-47 μgl cadmium alters the distribution of separation times when precopula pairs of G. pu7ex are disrupted by the invertebrate anaesthetic 2- phenoxyethanol. Precop1la is directly disrupted by exposure to cadmium (0.1-12.7 mgl )_ýut recovery can follow. Pretreatment with cadmium (3-140 μgl ) for 24 hours, of similarly sizeci male G. pulex and subsequent exposure to 0.13 and 2.23 μgl while in competition for access to a female may increase tolerance and enhance reproductive success, or initiate irreversible toxic effects and impair competitive ability. Exposure of female G. pulex-1to 2.0 and 9.6 μg1 , and female A. aquaticus to 40.2 pgl cadmium pre-fertilization reduces their fecundity. Brood development times of G. pulex and A. aquaticus exposed to 2.1 and 12.4 μg1-1 cadmium postfertilization are extended by 2 and 2.7 days respectively. The embryonic development and abortion during brooding are described in detail for A. aquaticus. An explanation of reduced final brood size in Asel7us is Postulated. Growth of juveniles of both test species exposed during brooding is assessed. Single and repeated 24 hour field simulations of acidic deposition demonstrate increased host sensitivity of G. pulex infected with P. 7aevis. The effects of low pH and elevated aluminium concentrations are mitigated to some extent by liming. Six hour field simulations of the individual components of farm waste demonstrated that infected gammarids were more susceptible under conditions of low dissolved oxygen than uninfected conspecifics.

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16

Tizini, Omar Abdullah. "Heavy metal concentrations in plaice (Pleuronectes platessa L.) from the North Eastern Irish Sea and their possible effects on growth". Thesis, University of Salford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272959.

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17

Millward, R. N. "The effects of chronic and acute metal-enrichment of the nematode community structure, composition and function in Restronguet Creek, SW England". Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296865.

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18

Leaver, Michael J. "Studies on the effects of oiled drill cuttings on marine sediments and on the hepatic cytochrome P-450 monooxygenases of plaice". Thesis, University of Aberdeen, 1987. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU010249.

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Section 1 deals with the effects of four low toxicity oiled drill cuttings samples and one diesel oiled cuttings sample on marine sediments. The sediments were contained in 18 onshore tank systems and, after equilibration for 3 months, cuttings were added at levels comparable to those found at about 500m from North Sea oil installations. Tanks containing uncontaminated sediments acted as controls. All contaminated tanks showed identical changes in redox profiles, becoming most reduced after 3 months and gradually recovering thereafter. The highest sulphide levels were recorded in tanks with the highest total oil and n-alkane levels and these reached a peak after 3 months before declining. Levels were still elevated after 15 months in all tanks. Total oil concentrations declined in all tanks over the period of the experiment, n-alkanes and naphthalenes being degraded first. A substantial decline in nematode abundance was observed in all treated tanks in the first month following cuttings application, after which the decline in diesel and the highest oil loaded low tox tanks continued more gradually. Nematode numbers in low tox tanks with lower oil loadings showed fluctuations with abundances greater than that of controls at some points. Interstitial copepods were eliminated in all tanks within the first three months and controls showed general declines over the experimental period. End/opibenthic copepods showed a more varied response with low tox treatments exhibiting enhanced populations, those with lowest oil levels showing the greatest abundances. Abundances in control and diesel treated tanks remained low and constant throughout the experiment. In the first few days after cuttings treatment the greatest evacuation rates for the burrowing bivalve Tellina were recorded from diesel treated sediments followed by the low tox treatments in order of oil loading. It is concluded that the long and short-term impact of diesel cuttings is greater than that of low tox cuttings containing equal oil concentrations. Section 2 deals with the effects of chemical inducing agents, drilling fluid base-oils, oiled drill cutting contaminated sediments and time of year on the hepatic cytochrome P-450 dependant monooxygenase system of the marine flatfish plaice (Pleuronectes platessa). Intraperitoneal injection of 3-methylcholanthrene, Aroclor 1254 and isosafrole greatly enhance several hepatic monooxygenase activities, with each inducing agent producing a slightly different profile of activity both in the presence and absence of a naphthoflavone in vitro. Intraperitoneal injection of oils from diesel and a low tox drilling fluid also induced several monooxygenase activities, and these oils also differed slightly in their induction profiles. These results suggest that more than one isozyme is responsive to chemical induction in the livers of these fish. Induction of monooxygenase was also demonstrated in fish exposed to cuttings contaminated sediments. Plaice exhibit a seasonal cycle for the basal levels of monooxygenase activity. These results are compared with similar work on rats and other fish species and the implications for environmental monitoring, carcinogenicity and reproduction are discussed.

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19

Mejía, Manuel. "Effects of water table management on water quality and strip cropped corn-soybean yields". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27378.

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A two-year field study was carried out in eastern Ontario to investigate the effects of water table management (WTM) on water quality and crop yields. Corn (Zea mays L.) and soybean (Glycine max Merr.) were planted in alternate strips across the three treatments of 50 cm controlled water table (CWT), 75 cm CWT and free drainage (FD). Drainflow volume and nitrate-N concentration of the drainage water were measured. Soil samples were collected and analysed for total N, P, K, available N, soil moisture and organic matter levels. Chlorophyll-meter readings and plant harvest parameters were also measured. Rainfall, soil and air temperatures were recorded throughout the growing seasons.
The obtained data show that in 1995, the CWT plots significantly increased total drainflow, as compared to FD. In 1996, overall drainflow and nitrate concentrations were significantly reduced. Both the corn and soybean yields were higher with WTM than with FD for both years. (Abstract shortened by UMI.)

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20

Boryslawskyj, Michael. "The dynamics and effects of persistent organochlorine insecticides in a freshwater system". Thesis, University of Huddersfield, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292246.

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21

Ruiz, Jose Miguel. "Metallic pollution in estuaries, with special reference to the effects of tributyltin (TBT) and copper on the early life stages of Scrobicularia plana (Mollusca: Bivalvia)". Thesis, University of Plymouth, 1993. http://hdl.handle.net/10026.1/2480.

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During the 1980s a decline in populations of the bivalve Scrobicularia plana was noted in several U.K. estuaries: tributyltin (TBT) was suspected of being the cause although its toxicity to adults could not be demonstrated except at elevated concentrations; disappearance of clam populations has been also observed in other European countries. Laboratory tests have revealed that: i) D-larvae hatching from embryos after 48 hours in TBT concentrations of 188 ngSn/l amounted to < 50% of control values, and doses of 364 ngSn/l or 20 µgCu/l prevented normal development in = 90% of embryos. ii) planktonic veliger larvae exposed for 10 days to nominal TBT doses ≥ 50 ngSn/l grew at rates which, at maximum, were one third of that exhibited by controls. iii) settling pediveligers subjected for 30 days to levels of TBT ≥70 ngSn/l suffered significant mortalities, and postlarvae kept at 23 ngSn/l displayed some shell growth which was both substantially reduced and grossly abnormal. iv) exposure for 30 days to 2! 300 ngSn/l or ≥20 µgCu/l impaired the burying activity in sand of small spat, and juveniles reared in TBT solutions at ≥ 28 ngSn/l grew significantly less than those in the control treatment. v) while small spat held in heavy metal polluted sediment suffered massive mortalities in 12 days, juveniles exposed for 36 days to butyltin contaminated sediment (0.4 µgSn/g) did not display any limited survival, but both their growth and burying activity were significantly reduced relative to those of juveniles kept in control sediments. It is concluded that in U.K. coastal areas where TBT in water during the summer-autumn months ranged from = 20 ngSn/l to = 200 ngSn/1 (i.e. = 50-500 ngTBT/l) and Scrobicularia plana populations disappeared or declined markedly, a cause-effect relationship is most likely to exist between the former and the latter through the deleterious effects of the chemical on the early life stages of the clam; in addition, the continued presence of sediment-bound TBT may render mudflats unsuitable for the development of larval and juvenile bivalves.

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22

AlKindi, Abdulaziz Yahya Ahmed. "The effects of the water-soluble fraction of crude oil on flounders and larvae of turbot". Thesis, University of Exeter, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260638.

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23

Wong, Tiow P. "Polyacrylamide (PAM) Effects on Viruses and Bacteria Transport in an Unsaturated Oxisol". Thesis, Water Resources Research Center, University of Hawaii at Manoa, 2001. http://hdl.handle.net/10125/22251.

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Experiments were to study the effects of anionic polyacrylamide (PAM) on viruses and bacteria movement in soil. A water pollution problem which affects all areas with significant rainfall is soil erosion and subsequent transport of soil and all land-based pollutants. In recent year, high molecular weight polymers, such as anionic polyacrylamides (PAMs), have been used for soil erosion control and subsequent environmental problems. PAM is found to enhance infiltration. Land application of manure, sludge, and wastewater is common in many areas of the world, including the United States. Bacteria, viruses and other pathogens can be found in these waste materials. Studies must be conducts to evaluate if the use of polymers will allow water pollution constituents such as chemicals, pesticides, and microbial pathogens to reach groundwater in aquifer.
Water Resources Research Center; Civil Engineering Department of University of Hawaii at Manoa

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Arrueta, Antequera Lourdes D. "Simulating the effects of behavioral and landscape heterogeneity on non-point source pollution". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1589943030581552.

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25

Sharifi, Abdol Rahim. "Heavy-metal pollution and its effects on recent foraminiferids from Southampton Water, southern England, UK". Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316316.

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26

Wallace, Katherine Hay. "Trading pollution for water quality : assessing the effects of market-based instruments in three basins". Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39938.

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Abstract (sommario):

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2007.
Includes bibliographical references (p. 83-90).
Since its passage in 1972, the majority of pollution reduction under the federal Clean Water Act has resulted from technology-based limits imposed on point source dischargers. However, most U.S. water bodies are unmonitored and of those that are, between 40 and 50 percent remain impaired. Given this limited progress, the U.S. Environmental Protection Agency, multiple state agencies, and non-governmental organizations have proposed water quality trading as a cost-effective means to achieve pollution reductions from point and nonpoint sources. To determine whether these programs actually achieve cost-effective pollution reduction in practice that they promise in theory, I evaluate direct and indirect outcomes associated with three water quality trading cases: the Grassland Area Farmers Tradable Loads Program in California's San Joaquin Valley; the Tar-Pamlico River Basin Nutrient Offset Program in North Carolina; and the Long Island Sound Nitrogen Credit Exchange in Connecticut. Although reallocating reduction efforts through trades to achieve cost-effective solutions is supposedly the major benefit of market-based instruments, only dischargers in the Long Island Sound Nitrogen Credit Exchange actively traded.
(cont.) The Grassland Area Farmers abandoned trading in favor of a more affordable and heavily subsidized management strategy, and members of the Tar-Pamlico Basin Association removed pollution onsite because reductions were less costly than expected and uncertainty over Offset Program parameters impeded planning around trades. Dischargers in the two cases also hesitated to trade because political transaction costs that trading imposed on relationships among entities did not outweigh perceived savings. Connecticut mitigated these costs and uncertainty by administering the Nitrogen Credit Exchange. The major contributions of market-based instruments across cases were facilitating dischargers' willingness to accept more stringent regulations and increasing the institutional capacity for watershed management by encouraging formation of organizations along hydrologic boundaries and information collection and dissemination. These benefits are attributable to the decentralized governance structure in general rather than economic incentives specifically, suggesting that policymakers should consider other decentralized approaches to watershed management.
(cont.) If policymakers want dischargers to actively trade, they should design parameters that mitigate uncertainty, market distortions, and political transaction costs. Even if trades never occur, however, indirect outcomes associated with market-based instruments are significant given the ongoing challenges to water quality improvement under the Clean Water Act.
by Katherine Hay Wallace.
M.C.P.

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27

Redick, Melinda. "Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles". Thesis, University of North Texas, 2002. https://digital.library.unt.edu/ark:/67531/metadc3119/.

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This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the hypotheses. Although the rate of predation was lower, tadpoles exposed to higher Cu concentrations were on average, 1.47 cm in total body length. Those exposed to 0.93 mg/L averaged 0.86 cm. After being placed into clean water, treatment tadpoles recovered after 20 days.

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28

Gheorghiu, Cristina. "Concentration-dependent effects of waterborne zinc on the interactions between Gyrodactylus turnbulli (Monogenea) and the guppy (Poecilia reticulata)". Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102979.

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This research investigated the effects of waterborne zinc (Zn) on the interactions between guppies, Poecilia reticulata (Peters), and Gyrodactylus turnbulli Harris, 1986, a monogenean parasite of its skin and fins. The first objective was to determine if sublethal concentrations of waterborne Zn (up to 240 mug/L added to artificial freshwater) exerted a concentration-dependent effect on the population dynamics of Gyrodactylus on isolated guppies. Whereas survival of uninfected fish was unaffected, mortality of infected fish increased linearly with increasing Zn concentration. In addition, the improved parasite population growth at concentrations up to 120 mug Zn/I suggested either that the elevated Zn promotes survival and/or reproduction of the parasite, or impairs host defense mechanisms. Analysis of lifetime survival and reproduction of individual parasites on and off the fish revealed Zn toxicity to the parasite as survival of detached parasites decreased linearly with increasing Zn concentration and parasite survival on the host was also lower at the highest Zn concentrations. Also, all morphological parameters decreased linearly in response both to increasing concentration and duration of exposure to waterborne Zn. The guppy epidermis responded rapidly to both infection and waterborne Zn, and the cumulative effects of these combined stressors were synergistic for epidermal thickness and mucous cell numbers, but antagonistic in terms of mucin composition. Both Zn and infection induced mucous production, but at elevated Zn concentrations and/or at high parasite burdens, the capacity for continued mucous production was apparently exceeded. I hypothesize that this condition is favorable for parasite survival because of the impaired host response; but unfavorable for host survival because of the high numbers of pathogenic parasites and the inability to control entry of Zn into host tissues. In conclusion, sublethal concentrations of waterborne Zn are more detrimental to the infected host than to the parasite.

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29

Lang, David A. King Ryan Steven. "Effects of nutrient enrichment on alkaline phosphatase activity and nitrogen fixation potential in stream periphyton". Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5071.

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30

Tessier, Catherine. "Ecotoxicological impacts of zebra mussels, Dreissena polymorpha, a new food source for lesser scaup, Aythia affinis". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=34468.

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Zebra mussels (Dreissena polymorpha) have invaded a great proportion of the waters of the eastern part of North America. This mollusk may be a useful sentinel species for bioaccumulation of heavy metals and organic contaminants in aquatic ecosystems. The zebra mussel's capacity to bioaccumulate cadmium at environmentally relevant exposure and to sequester metals in metal-binding proteins, metallothioneins, was investigated. Elevated (relative to control) concentrations of Cd$ sp{2+}$ were detected in Dreissena exposed to $ ge$2 $ mu$g Cd/liter suggesting that zebra mussels cannot regulate Cd$ sp{2+}$ of trace exposure concentration. More than 85% of the measured Cd$ sp{2+}$ was bound to metallothioneins.
Lesser scaup (Aythya affinis) was assessed as a model species for potential impacts of zebra mussels on higher trophic levels. The feasibility of incubating and rearing scaup in semi-natural conditions was evaluated. A series of biomarkers was assessed in 3 groups of scaup fed a contaminant-free diet or diets containing zebra mussels from the St-Lawrence River or Lake Erie.
Lesser scaup proved to be a suitable species to raise in captivity providing daily water misting through out incubation and strict hygiene conditions during brooding. A hatching success of 89% was achieved. Appropriate housing, feeding and bathing conditions yielded low (3%) post-hatching mortality.
Phagocytosis and respiratory burst activities of heterophils of scaup were suppressed after 6 weeks of feeding on zebra mussels, compared to the control group. These two heterophilic functions were negatively correlated with the incidence of pododermatitis (bacterial feet infection), suggesting a suppression of the non specific immunity. Increased liver/body mass ratio and decreased hepatic vitamin A (retinol and retinyl palmitate) concentrations were observed in scaups fed zebra mussels. Lipid accumulation and glycogen overload were found in the livers of scaups fed mussels from the St-Lawrence River and the Lake Erie groups, respectively. These immunological, biochemical and histopathological biomarkers show promise for monitoring "early" injury and may help in the understanding of health impairment of different species of waterfowl exposed to xenobiotics via contaminated food sources.

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31

Sarakinos, Helen C. "The use of chemical analyses, bioassays and benthic biomonitoring in the toxicity assessment of complex industrial effluents". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0019/MQ44271.pdf.

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32

Mohan, C. V. "Modulatory effects of cadmium and copper on the susceptibility and immune response of common carp, Cyprinus carpio (L) to selected pathogens". Thesis, University of Stirling, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280056.

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33

Thomas, Kevin Victor. "Characterisation and environmental effects of unresolved complex mixtures of hydrocarbons". Thesis, University of Plymouth, 1995. http://hdl.handle.net/10026.1/462.

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Abstract (sommario):

The gas chromatograms of crude oil hydrocarbons reveal both resolved and unresolved components. The unresolved feature is commonly referred to as the unresolved complex mixture (UCM). UCMs are thought to result from the co-elution of complex mixtures of hydrocarbons with similar chemical properties and become more obvious as resolved components are removed by processes such as weathering and refining. Consequently UCMs are a prominent feature in oil-polluted sediments, biodegraded crudes and refineiT products. The characterisation of both aliphatic and aromatic unresolved complex mixtures (UCMs) of hydrocarbons, as well as their possible effects on the environment, is described. An aliphatic hydrocarbon UCM isolated from the base oil of Silkolene 150 lubricating oil was characterised by a combination of micro vacuum-distillation and oxidative degradation. Vacuum-distillation produced six distillate cuts and a residue which were all highly unresolved by GC (ca. 951/6). The average molecular weight of each cut was determined by probe CIMS (310 - 440 Daltons), and varied by -20 Daltons. Cr03 oxidation of each fraction yielded similar distributions of n-monocarboxylic acids, ketones and lactones as well as C02 (ca. 6%). The resolved products of oxidation suggest that the aliphatic UCM is a rather homogeneous mixture of highly branched alkanes. However a significant amount of the products remain unresolved (UCMox.; ca. 70-95%). A retro -structural analysis approach, using an aromatic UCM oxidant (Ru04), combined with a mass balance approach, was used to characterise aromatic UCMs. Following reproducibility studies and the analysis of authentic aromatic compounds, the method was applied to the characterisation of unresolved aromatic refinery oil fractions and a suite of aromatic UCM distillate fractions. Selected refinery oils were separated into mono-, di-, tri- and tetraaromatics by BPLC and shown to be mainly unresolved by GC (ca. 80%). Ru04 oxidation of these fractions yielded DCM soluble products (24 - 74%), water soluble products (0 - 10%) and C02 (12 -78%). The principal resolved products in each oxidation were monocarboxylic acids and dicarboxylic acids which were used to reconstruct precursor compounds. Vacuum-distillation of Tia Juana Pesado crude (Venezuela) gave six cuts and a residue which were analysed by GC, 1H NMP, UV and probe CIMS to obtain molecular weight (171 - 301 Daltons) and broad structural information whilst Ru04 oxidation was used to obtain molecular information via the retro -structural analysis approach. This showed that the aromatic UCM was in fact highly aliphatic and contained alkyl and cycloalkyl tetralins. A significant advancement in the quantitative characterisation of UCMOx. and subsequently the characterisation of aromatic UCMs was made. Ion cyclotron resonance spectrometry (ICR) was used to characterise the Ru04 oxidation products of selected refinery fractions. Analysis of the oxidation products of a monoaromatic refinery fraction indicated the presence of monocarboxylic acids (Cl - C21; 58%) and alicyclic carboxylic acids (C7 - C19; 16%), a hydrogenated monoaromatic sample contained monocarboxylic acids (Cl - C20; 30%), dicarboxylic acids (C2 - C11,7%) and alicyclic carboxylic acids (C7 - C18; 11%) , whilst a diaromatic fraction contained monocarboxylic acids (C10 - C19; 7%), alkyl phthalic acids (C8 - C17', 17%) and cycloalkyl phthalic acids (C11 - C15; 3%). Retro -structural analysis suggests that the nonhydrotreated monoaromatic UCM is mainly comprised of alicyclic and alkyl substituted benzenes, the monoaromatic UCM isolated from the hydrotreated oil of alky'l and cycloalkyl substituted tetralins and the diaromatic fraction of alkyl and cycloalkyl naphthalenes. This was supported by, FIMS analysis of the fractions prior to oxidation. As an investigation of the environmental toxicity of UCMs, the effect of a saturated aliphatic UCM, and its chemical oxidation products, on the feeding rate of mussels (Mytilus edulis), was investigated. The UCM had little effect, whilst oxidation resulted in an increase in toxicity. The non-toxic nature of the hydrocarbons was attributed to their low aqueous solubility, whilst oxidation resulted in the formation of products NNith a greater solubility, which were sufficiently hydrophobic to be narcotic toxicants. Parts of this work have been published [Thomas et al., (1993) Organic Geochemistry, Falch Hurtigtrykk, Non%-ay(A bstract), 717-719; Thomas et al., (1995) [Vater Research. 29,371-382]. iv

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34

Love, Danielle M. Matthews Robin A. "Effects of salmon-derived nutrients on an artificial stream system /". Online version, 2009. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=321&CISOBOX=1&REC=9.

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35

Alloy, Matthew Michael. "Effects of Suspended Multi-Walled Carbon Nanotubes on Daphnid Growth and Reproduction". Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc28383/.

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Abstract (sommario):

Multi-walled carbon nanotube aggregates can be suspended in the aqueous phase by natural organic matter. These aggregates are ingested by filter feeding zooplankton. Ingested aggregates result in decreased growth and decreased reproduction. These effects may be caused by reduction in energy input from normal feeding behavior. pH alters natural organic matter structure through changes in electrostatic repulsion. Altered natural organic matter structure changes multi-walled carbon nanotube aggregate size. This size variation with variation in pH is significant, but not large enough a change in size to alter toxicity, as the aggregate size range remains well within the particle size selection of the organisms.

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36

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.

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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.

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37

Chernicharo, Carlos Augusto de Lemos. "The effect of temperature and substrate concentration on the performance of U.A.S.B. reactors". Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308963.

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38

Al-Rasheid, Khaled A. S. "The effect of heavy metals on the marine ciliate Euplotes mutabilis (Tuffrau, 1960)". Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358875.

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39

Tijunelyte, Inga. "Development of SERS nanosensor for detection of water pollution". Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCD007/document.

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La pollution des eaux par des composés organiques constitue un problème mondial majeur. Parmi cescomposés, les molécules aromatiques de faibles masses molaires constituent une famille largementrependue dont la toxicité et la cancérogénicité est avérée et bien documentée. La Directive-CadreEuropéenne sur l’eau (2000/60/EC, 2006/118/EC and 2006/11/EC) établit des normes de qualitéenvironnementales ayant pour objectif d’améliorer la qualité des eaux. Dans ce contexte, ledéveloppement d’outils analytiques robustes, permettant de détecter et de quantifier précisément et insitula présence de polluants dans les eaux est d’une importante primordiale. L’objectif principal de cetteétude est l’élaboration de nanocapteurs sensibles, robustes et réutilisables, permettant l’analyse depolluants organiques dans les eaux grâce à la Spectroscopie Raman Exaltée de Surface (SERS).Tout d’abord, une attention particulière a été portée à la sélection des récepteurs et des différentesstratégies de fonctionnalisation permettant d’élaborer un nanocapteur SERS capable de pré-concentrerles polluants visés. L’utilisation d’antigènes et de fragments d’antigènes (F(ab)2) a montré des résultatsprometteurs pour l’élaboration de nanocapteurs très sélectifs. Une seconde approche basée surl’utilisation de cavitants ou molécules hôtes, telles que les cyclodextrines (CDs), a été développée. Lapré-concentration sélective des polluants grâce à leur taille a été démontrée par spectroscopie Raman etSERS. Enfin, grâce à la possibilité d’identification moléculaire en milieu complexe offerte par laspectroscopie SERS, une approche permettant une pré-concentration non spécifique des polluants a étédéveloppée. Pour ce faire, différents sels de diazoniums (DSs) ont été synthétisés et greffés à la surfacedes nanocapteurs afin de créer une couche hydrophobe permettant la pré-concentration et la détection decomposés apolaires. Les performances de ces nano-capteurs ont été démontrées pour la détection de plusieurs PAHs apolaires
Environmental water pollution by organic compounds is in continues worldwide concern. Low molecular mass aromatic molecules consisting in benzene rings have received considerable attention due to a documented significant toxicity and carcinogenicity. Within the objectives of the European Water Framework Directives (2000/60/EC, 2006/118/EC and 2006/11/EC) aiming in water quality improvement, the development of analytical tools allowing in-situ accurate and sensitive detection is of primary importance and would be a meaningful innovation. With this regard, the main scope of this study was to design sensitive, reproducible, specific and reusable nanosensor for the detection of organic pollutants in environmental waters using Surface Enhanced Raman Spectroscopy (SERS).During this study the main attention was paid to the selection of suitable receptors and strategies for SERS nanosensor surface functionalisation in order to preconcentrate targeted pollutants. The application of antibodies and antigen binding fragments (F(ab)2) for surface decoration was found to be promising approach for highly selective nanosensor design. Another strategy exploited during this study was related with an application of cyclodextrins (CDs). Using Raman and SERS spectroscopies the size selective encapsulation of analytes was demonstrated. Finally, taking advantage of molecular identification in the complex environments offered by SERS technique, nanosensors providing non-specific molecular pre-concentration was considered. For this purpose several diazonium salts (DSs) were studied and applied to the surface functionalisation to create highly hydrophobic coating layer. The performance of such nanosensor was evaluated by detection of aromatic pollutants

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40

Chingombe, Wisemen. "Effects of land-cover - land-use on water quality within the Kuils - Eerste River catchment". Thesis, University of Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_5893_1373463134.

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Abstract (sommario):

The most significant human impacts on the hydrological system are due to land-use change. The conversion of land to agricultural, mining, industrial, or residential uses significantly alters the hydrological characteristics of the land surface and modifies pathways and rates of water flow. If this occurs over large or critical areas of a catchment, it can have significant short and long-term impacts, on the quality of water. While there are methods available to quantify the pollutants in surface water, methods of linking non-point source pollution to water quality at catchment scale are lacking. Therefore, the research presented in this thesis investigated modelling techniques to estimate the effect of land-cover type on water quality. The main goal of the study was to contribute towards improving the understanding of how different land-covers in an urbanizing catchment affect surface water quality. The aim of the research presented in this thesis was to explain how the quality of surface runoff varies on different land-cover types and to provide guidelines for minimizing water pollution that may be occurring in the Kuils-Eerste River catchment. The research objectives were
(1) to establish types and spatial distribution of land-cover types within the Kuils-Eerste River catchment, (2) to establish water quality characteristics of surface runoff from specific land-cover types at the experimental plot level, (3) to establish the contribution of each land-cover type to pollutant loads at the catchment scale. Land-cover characteristics and water quality were investigated using GIS and Remote Sensing tools. The application of these tools resulted in the development of a land-cover map with 36 land classifications covering the whole catchment. Land-cover in the catchment is predominantly agricultural with vineyards and grassland covering the northern section of the catchment. Vineyards occupy over 35% of the total area followed by fynbos (indigenous vegetation) (12.5 %), open hard rock area (5.8 %), riparian forest (5.2 %), mountain forest

(5 %), dense scrub (4.4 %), and improved grassland (3.6 %). The residential area covers about 14 %. Roads cover 3.4 % of the total area. Surface runoff is responsible for the transportation of large quantities of pollutants that affect the quality of water in the Kuils-Eerste River catchment. The different land-cover types and the distribution and concentration levels of the pollutants are not uniform. Experimental work was conducted at plot scale to understand whether land-cover types differed in their contributions to the concentration of water quality attributes emerging from them. Four plots each with a length of 10 m to 12 m and 5 m width were set up. Plot I was set up on open grassland, Plot II represented the vineyards, Plot III covered the mountain forests, and Plot IV represented the fynbos land-cover. Soil samples analyzed from the experimental plots fell in the category of sandy soil (Sa) with the top layer of Plot IV (fynbos) having loamy sand (LmSa). The soil particle sizes range between fine sand (59.1 % and 78.9 %) to coarse sand (between 7 % and 22 %). The content of clay and silt was between 0.2 % and 2.4 %. Medium sand was between 10.7 % and 17.6 %. In terms of vertical distribution of the particle sizes, a general decrease with respect to the size of particles was noted from the top layer (15 cm) to the bottom layer (30 cm) for all categories of the particle sizes. There was variation in particle size with depth and location within the experimental plots.Two primary methods of collecting water samples were used
grab sampling and composite sampling. The quality of water as represented by the samples collected during storm events during the rainfall season of 2006 and 2007 was
used to establish
water quality characteristics for the different land-cover types. The concentration of total average suspended solids was highest in the following land-cover types, cemeteries (5.06 mg L^-1), arterial roads/main roads (3.94 mg L^-1), low density residential informal squatter camps (3.21 mg L^-1) and medium density residential informal townships (3.21 mg L^-1). Chloride concentrations were high on the following land-cover types, recreation grass/ golf course (2.61 mg L^-1), open area/barren land (1.59 mg L^-1), and improved grassland/vegetation crop (1.57 mg L^-1). The event mean concentration (EMC) values for NO₃-N were high on commercial mercantile (6 mg L^-1) and water channel (5 mg L^-1). The total phosphorus concentration mean values recorded high values on improved grassland/vegetation crop (3.78 mg L^-1), medium density residential informal townships (3mgL^-1) and low density residential informal squatter camps (3 mg L^-1). Surface runoff may also contribute soil particles into rivers during rainfall events, particularly from areas of disturbed soil, for example areas where market gardening is taking place. The study found that different land cover types contributed differently to nonpoint source pollution. A GIS model was used to estimate the diffuse pollution of five pollutants (chloride, phosphorus, TSS, nitrogen and NO₃-N) in response to land cover variation using water quality data. The GIS model linked land cover information to diffuse nutrient signatures in response to surface runoff using the Curve Number method and EMC data were developed. Two models (RINSPE and N-SPECT) were used to estimate nonpoint source pollution using various GIS databases. The outputs from the GIS-based model were compared with recommended water quality standards. It was found that the RINSPE model gave accurate results in cases where NPS pollution dominate the total pollutant inputs over a given land cover type. However, the N-SPECT model simulations were too uncertain in cases where there were large numbers of land cover types with diverse NPS pollution load. All land-cover types with concentration values above the recommended national water quality standard were considered as areas that needed measures to mitigate the adverse effects of nonpoint pollution. The expansion of urban areas and agricultural land has a direct effect on land cover types within the catchment. The land cover changes have adverse effect which has a potential to contribute to pollution.

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41

Dando, Chrtistine. "The effect of zinc on physiological function in Gammarus pulex : a between-individual variation approach". Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274947.

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42

Shaw, Peter James. "The effect of humic substances on the speciation and bioavailability of iron and phosphate in lakes". Thesis, Lancaster University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239867.

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43

Tennakoon, Nihal Ananda. "Effect of heavy metal contaminated sewage sludge on biological and chemical properties of coniferous forest soils". Thesis, University of Aberdeen, 1993. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU549118.

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Abstract (sommario):

A field study was carried out at Ardross forest, northern Scotland where heavy metal contaminated sewage sludge had been applied to a peaty podzol at rates of 500 (low) and 1000 (high) kg N ha-1 before tree (Sitka spruce) planting. Nitrogen mineralisation rates determined by field incubation of sealed cores ranged from 3.7 to 4.5 and 7.3 to 9.4 kg N h-1 over the growing season (May to September, 1991) in soils amended with low and high rates of sludge respectively. For the control soil, to which no sludge had been added, mineralisation rates ranged from 2.4 to 2.9 kg N ha-1. Mineralisation of residual sludge was estimated to be 0.56&'37 and 1.14&'37 in 1991, 8 years after sludge application at the low and high rates, respectively. Soils brought back to the laboratory and repacked according to the field profile enabled microcosm studies to be carried out to further investigate possible changes caused to N-cycling processes in coniferous forest soil due to application of heavy metal contaminated sewage sludge, and to consider possible mechanisms of any such changes. In the microcosm study, the two rates of application of sewage sludge increased N mineralisation. A linear relationship was apparent between N mineralisation and the rate of sludge application. Increased N mineralisation was associated with an increase in active fungal mycelium, biomass N and soil animal population densities. The availability of Cd, Cu, Mn, Pb and Zn was found to be related to the time of the year, with highest availability in Spring and Summer, and lowest availability in Winter. There was no evidence of any adverse effects in terms of heavy metals on the studied biological parameters and mineralisation rates in the field and microcosm studies. Total N, pH and moisture also increased due to sludge application.

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44

Warwick, Oliver William Tindle. "The use of a biomarker to assess the effect of xenobiotic exposure on the freshwater invertebrate Gammarus pulex". Thesis, University of Sheffield, 1997. http://etheses.whiterose.ac.uk/10191/.

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Contamination of freshwaters is of concern because of its effect on ecosystem health. The effect of contamination can be assessed at all levels of biological organisation, from the ecosystem level to the molecular level. At the biochemical level, enzymes that are involved in the detoxification of organic chemical contaminants are useful as markers of contaminant exposure as they are often one of the first systems to respond to chemical exposure. Furthermore, changes in the activity of these enzymes may be indicative of effects at higher levels of biological organisation. In this study, the use of the detoxification enzyme glutathione stransferase (E. C. 2.5.1.18) (GST) in the freshwater invertebrate Gammarus pulex (Crustacea: Amphipoda), as a biomarker of organic xenobiotic exposure and effects was assessed. Toxicant induced changes in GST activity were related to changes in energy status and physiological energetics. A GST assay was developed that allowed the rapid analysis of GST activity in up to ninety individual animal samples simultaneously. Optimum sample handling and assay conditions were determined for the assay of GST in G. pulex, and extrinsic factors (e. g. environmental temperature, feeding and holding conditions) and intrinsic factors (e. g. body size), affecting variability of GST activity in G. pulex were assessed The effect of exposure to the organic xenobiotics lindane( an organochlorinein insecticide) and alcohol ethoxylate( a non-ionic surfactand detergent)on GST activity in G.pulex was described. The magnitude and duration of the response of GST activity to exposure to both chemicals was assessed under laboratory conditions and with alcohol ethoxylateu, sing outdoor artificial streams. The use of GST as a marker of pesticide exposure in field populations of G. pulex that were subject to pesticide contamination was studied in comparison with animals from non-contaminated, reference sites. The differences in GST activity between animals from a contaminated site and clean site were investigated by short-term and long-term exposure to lindane in the laboratory. Changes in energy status and physiological energetics were investigated in G. pulex on exposure to lindane by measuring glycogen concentration and scope for growth. Measuring these parameters on short-term and long-term exposure to lindane allowed the sensitivity of these responses to be related to the GST response and allowed the energetic cost of exposure to be assessed. It was concluded that increase in GST activity may providea rapid and sensitive biomarker of xenobiotic exposure in the short-term and in populations subject to pesticide contamination. The affect on GST activity may be indicative of effects at higher levels of biological organisations, such as scope for growth and glycogen concentration However, GST activity is affected by a variety of intrinsic and extrinsic factors and should therefore be used only asp art of a comparative study. Because of the transient nature of the GST response in situ assessments should be based on 24-hour exposure periods.

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45

Poff, Boris, e Daniel G. Neary. "International Co-Operative Program on Assessment and Monitoring of Air Pollution Effects on Forests: The Sierra Ancha Experimental Forest, Arizona". Arizona-Nevada Academy of Science, 2008. http://hdl.handle.net/10150/296685.

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46

Watson, Jay L. "Collective action problems and cumulative effects : addressing pollution of marine waters in Hood Canal, Washington /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5515.

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47

Laopaiboon, Lakkana. "The effect of sublethal and lethal concentration of biocides on the performance and characteristics of rotating biological contactors and the properties of their biofilms". Thesis, University of Hertfordshire, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369763.

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48

Chivers, Alicia M. "Investigating the Effects of 17α-Ethynylestradiol on Mitochondrial Genome Stability". PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2989.

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Abstract (sommario):

Environmental toxicants are ubiquitous throughout the environment as a result of human activity. Among these toxicants, environmental estrogens are a category of particular concern due to their environmental prevalence and potency in altering reproductive traits. While many studies have addressed the detrimental effects of environmental estrogens on both aquatic and terrestrial organisms, few have analyzed the potential for these compounds to alter mitochondrial function. Mitochondria are the primary energy-generating system for all eukaryotic life, supporting all aspects of development, metabolism, and growth. Each cell within the body contains many mitochondria which in turn contain multiple copies of their own DNA genome, mitochondrial DNA (mtDNA). Mutations in mtDNA are responsible for a wide range of human diseases such as metabolic syndromes, cancers, and obesity. Among these mitochondrial diseases many are characterized by increased levels of heteroplasmy, multiple mitochondrial DNA haplotypes within an individual. Increased heteroplasmy can alter normal mitochondrial function and influence disease initiation and progression. To date, no studies have investigated the effects of synthetic estrogens on mitochondrial genome stability. Synthetic estrogens have the capacity to bind to estrogen receptors and initiate estrogenic responses through translocation into the mitochondrion. Despite our knowledge about the relationship of heteroplasmy and disease, we still do not have a complete grasp of the mechanisms of heteroplasmic induction. Here we report our analysis of the effects of 17α-ethynylestradiol (EE2) exposure in three studies to investigate its effect on mitochondrial genome stability. Data analysis reveals a statistically significant relationship between EE2 exposure and increased heteroplasmic frequency.

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49

Womack, Michael. "Temporal effects on orhophosphate removal from municipal wastewater in a subsurface-flow constructed wetland". Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020163.

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Abstract (sommario):

Orthophosphate removal from wastewater in a subsurface-flow constructed wetland (SFCW) was studied during the fall of 1995. The SFCW consisted of a cell with an impervious liner, filled with 1.27 to 3.81 cm river rock and planted with common reeds (Phragmites australis) and soft-stem bulrushes (Scirpus validus). Municipal wastewater was pumped through the wetland and comparisons were made between inlet and outlet orthophosphate concentrations. Comparisons were also made at locations within the cell. A mean orthophosphate reduction of 62% with a range of 91% to 32% was observed for the duration of the study. An ANOVA test showed a significant reduction of orthophosphate in the wetland cell during the study. A regression analysis indicated that inlet wastewater temperatures played a significant role in orthophosphate removal, while outlet wastewater and ambient air temperature were not a significant factor.Keywords: Subsurface-Flow Constructed Wetlands, Orthophosphate, Municipal Wastewater, Water Chemistry, Nutrients.
Department of Natural Resources and Environmental Management

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50

Nallani, Gopinath C. "Determination of Bioconcentration Potential of Selected Pharmaceuticals in Fathead Minnow, Pimephales promelas, and Channel Catfish, Ictalurus punctatus". Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33189/.

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Abstract (sommario):

The primary objective of this work was to determine the tissue-specific bioconcentration factors (BCFs) of the selected pharmaceuticals: norethindrone (NET), ibuprofen (IBU), verapamil (VER), clozapine (CLZ) and fenofibrate (FFB) in two freshwater fishes: fathead minnow and channel catfish. BCF tests on fathead followed the standard OECD 42-day test while a 14-day abridged test design was used in catfish exposures. Additional objectives included a) comparing the measured BCFs to the US EPA's BCFWIN model predicted values, b) comparing the BCF results from the standard and reduced tests, and c) prediction of chronic risk of the pharmaceuticals in fish using the human therapeutic plasma concentrations. Each test included uptake and depuration phases to measure tissue-specific kinetic BCFs. The results indicated that all the pharmaceuticals, except IBU, have the potential for accumulation in fish. Estimated BCFs for NET, VER and FFB may not be significant in view of the current regulatory trigger level (BCF ≥ 2000); however, CLZ's BCF in the liver had approached the criterion level. Significant differences were noticed in the tissue-specific uptake levels of the pharmaceuticals with the following general trend: (liver/kidney) > (gill/brain) > (heart/muscle) > plasma. IBU uptake was highest in the plasma. When compared to the measured BCFs, predicted values for NET, IBU, VER and FFB were slightly overestimated but did not differ largely. However, the measured BCF of CLZ in the liver was approximately two-orders of magnitude higher than the predicted level. The tissue-BCFs for the two species were not widely different indicating the potential usefulness of the reduced BCF test. Comparison of fish and human plasma levels indicated that NET, CLZ and VER have the potential to cause chronic effects in fish.

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