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Wong, Wang-wah, and 黃宏華. "Trace organics pollution in the aquatic environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31252758.
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Wong, Wang-wah. "Trace organics pollution in the aquatic environment /." [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13498356.
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Cotín, Martínez Javier. "Birds as Bioindicators of Pollution in Aquatic and Terrestrial Environments." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/101099.
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Birds have been widely used as bioindicators. In this study we face the use of birds as bioindicators of metal pollution in two different scenarios of contamination: one that takes place in an aquatic environment, the Ebro river basin, and a second that occurs in a terrestrial environment, the Bolivian Andes.
In the case of the Ebro river basin, the pollution threat is a factory located at the river bend, close to Flix, that due to its long operational activity and along with the construction of a dam next to the plant around 1960, resulted in the accumulation of 200,000–360,000 tons of industrial wastes in the riverbed, occupying an area of 700 m of length and 60 m of width. In this study case we evaluated whether aquatic birds such as the Purple Heron reflect the potential pollutant exposure from Flix Reservoir among different riverine and deltaic areas, and assess their usefulness as bioindicators. Also we examined if the polluted wastes of Flix reservoir affect the levels of pollution of the habitats where waterbird populations of the Ebro Delta (situated 90 km downstream) forage and feed.
As results stable isotopes shown the high nitrification and lower carbon signatures in the river, and together with the niche width metrics, that Common and Sandwich Tern behave as strict specialists at the Ebro Delta, with narrow niche widths, while in the opposite way, Little Tern, Little Egret, Purple Heron, Night Heron and the Moorhen behave like generalists foragers, with broad niche widths. Mercury levels in nestlings of Purple Heron at Flix site and eggs of Audouin’s Gull, Little Tern and Common Tern ‘Banya’ at the Ebro Delta are high enough to be of special concern. Arsenic (specially used in combination with carbon signatures) discriminates outstandingly between marine and freshwater species. Both eggs and nestling feathers of Purple Herons are adequate bioindicators for trace element pollution, but nestling feathers present certain advantages. The six selected blood parameters (TOSC ROO*, TOSC OH*, BhCE, CbE, LDH and MN) provide the first evidence of an association of biological responses with pollutants in heron species.
The second study case takes place in Bolivia. Anthropogenic mining has taken place in the Bolivian Andes since at least the fifteenth century. Particularly the East of Oruro Department in the Eastern Andean Cordillera is affected by a long term history of mining. These mining activities were characterized by the deposition of large tailing piles, which accumulated in abandoned and active mines, where trace metals such as lead, arsenic, cadmium, and antimony could reach surface waters and soils, and so the biota. In this case we evaluated the potential of Tinamou species as sentinels of exposure to local trace metal pollution and studied different routes of lead accumulation into the sentinel species, in order to assess the usefulness of feather levels as a measure of the exposure to this pollutant.
As results we found that the detected small home ranges detected in Ornate Tinamou (lower than 1 km2) and their sedentary habits make of this species an adequate bioindicator of local pollution. We recommend feathers for future monitoring programs as they are a non invasive sample. Higher rates of histopathological damage were found in kidney at the polluted sites. We detected high levels of trace elements detected at the polluted sites in the two studied species of Tinamou (Ornate and Darwin Tinamou), many of them trespassing hazard levels. The calamus is the most suitable section for assessing the original endogenous lead levels in feather samples.En este estudio las aves serán utilizadas como bioindicadoras de contaminación por metales pesados en dos escenarios diferentes: el primero en un ambiente acuático, la cuenca del rio Ebro, mientras que el segundo tiene lugar en un ambiente terrestre, los Andes bolivianos. En el primer caso la fuente de contaminación es una fábrica localizada cerca de Flix, que produjo cientos de toneladas de lodos tóxicos. Así evaluamos si aves acuáticas como la Garza imperial reflejan la exposición potencial a los contaminantes de Flix entre zonas fluviales y deltaicas, comprobando su utilidad como bioindicadoras, y también examinamos si dichos residuos afectan a la contaminación de los hábitats donde la avifauna del Delta del Ebro se alimenta. Como resultados los isótopos estables mostraron la alta nitrificación y signaturas más bajas de carbono en el río y observamos que el Charrán común y patinegro actúan como especialistas en el Delta, mientras que Charrancito, Garceta común, Garza Imperial, Martinete y Gallineta de agua son generalistas, presentando amplios nichos tróficos. El mercurio en volantones de Garza Imperial en Flix y huevos de Gaviota de Audouin, Charrancito y Charrán común “Banya” en el Delta presentan valores alarmantes. El arsénico discrimina claramente entre especies marinas y dulceacuícolas. Ambos huevos y plumas son bioindicadores adecuados de contaminación, pero las plumas presentan más ventajas. El segundo estudio tiene lugar en los Andes Bolivianos, donde la actividad minera ha dado lugar a la acumulación de residuos. Evaluamos el potencial de las especies de Tinamúes como bioindicadoras de la exposición a dicha contaminación, incluyendo las diferentes vías de acumulación de plomo en las especies bioindicadoras. Como resultados, los pequeños territorios detectados y hábitos sedentarios hacen del Tinamú Pisacca un bioindicador adecuado de la contaminación local. Se recomienda el uso de plumas al son una muestra no invasiva. El mayor daño histopatológico se encontraron en muestras de riñón de las zonas contaminadas. La contaminación minera ha quedado de manifiesto con los altos niveles detectados en las dos especies estudiadas de Tinamú. El cálamo es la sección más adecuada para la evaluación de los niveles originales endógenos de plomo.
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Tayab, Muhammad Rehan. "Environmental impact of heavy metal pollution in natural aquatic systems." Thesis, Brunel University, 1991. http://bura.brunel.ac.uk/handle/2438/5503.
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The distribution of heavy metals between soil and soil solutions is a key issue in evaluating the environmental impact of long term applications of heavy metals to land. Contamination of soils by heavy metals has been reported by many workers. Metal adsorption is affected by many factors, including soil pH, clay mineralogy, abundance of oxides and organic matter, soil composition and solution ionic strength. The pH is one of the many factors affecting mobility of heavy metals in soils and it is likely to be the most easily managed and the most significant. To provide the appropriate level of protection for aquatic life and other uses of the resource, it is important to be able to predict the environmental distribution of important metals on spatial and temporal scales and to do so with particular emphasis on the water column concentrations. Regulatory levels reflected in water quality criteria or standards are based on water column concentrations. Predicting water column concentrations requires a consideration of the interactions of water column contaminants with both bed sediments and suspended particulates as critical components in the assessment. The adsorption behaviour of cadmium, copper, lead and zinc onto soils is studied under the various geo-environmental conditions of pH, concentration of adsorbate and adsorbent, and solution compositions. Experiments were conducted to determine the equilibrium contact time of various adsorbates for adsorbent in different systems. Experiments were also conducted to check the efficiency of various acid-mixtures to extract heavy metal from soils into the aqueous phase. The adsorption behaviour of heavy metals onto soils was also studied from sea-water system. Soils are characterized in terms of the role of clay minerals to remove the metals from the solution phase, back-ground levels of metals, maximum adsorption capacity to adsorb various heavy metals from different adsorption systems, and type of surface sites present. The experimental data of metal adsorption is described by Langmuir adsorption model. The adsorption data are also expressed in terms of surface loading, surface acidity, adsorption density, and affinity of soils for heavy metals in different adsorption systems. Ecological implications of changes in physical and chemical conditions in aquatic systems on heavy metals uptake by soils are also discussed. This research covers the following areas: the environmental impact of heavy metal discharge into the aquatic systems, the study of the mobility patterns of different heavy metals as function of geo-environmental conditions, and determination of the pathways and the ultimate fate of heavy metals in the environment.
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Halstead, Neal T. "Impacts Of Agrochemical Pollution On Aquatic Communities And Human Disease." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5870.
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The global human population is expected to exceed 9 billion individuals by 2050, putting greater strain on the natural resources needed to sustain such a population. To feed this many people, some expect agricultural production will have to double and agrochemical use will have to increase anywhere from two- to five-fold relative to the turn of the century. Although industrial agriculture has provided many benefits to society, it has caused declines in biodiversity, both directly (e.g., through conversion of habitat) and indirectly (e.g., through contamination of adjacent natural habitats). Agricultural activity has also been linked to increased prevalence and intensity of trematode infections in wildlife and humans - directly by increasing available aquatic habitat for the snail intermediate hosts of trematode parasites and indirectly by altering the biological composition of aquatic habitats in ways that increase snail density. While the effects of single agrochemical contaminants on aquatic communities and trematode disease risk have been examined, agrochemical pollution typically occurs as mixtures of multiple chemical types in surface waters and the effects of mixtures on aquatic communities have received less attention. Moreover, given the high number of chemicals approved for agricultural use, the number of potential combinations of agrochemicals renders testing all possible combinations implausible. Thus, there is a critical need to develop better risk assessment tools in the face of this complexity.
I developed and tested a theoretical framework that posits that the net effects of agrochemical mixtures on aquatic communities can be predicted by integrating knowledge of each functional group's 1) sensitivity to the chemicals (direct effects), 2) reproductive rates (recovery rates), 3) interaction strength with other functional groups (indirect effects), and 4) links to ecosystem properties. I conducted a freshwater mesocosm experiment to quantify community- and ecosystem-level responses to pairwise mixtures of four major agrochemical types (fertilizer, herbicide, insecticide, and fungicide) and single chemical treatments. The responses of biodiversity and ecosystem properties to agrochemicals alone and in mixtures were indeed predictable. Moreover, these results show that community ecology theory holds promise for predicting the effects of contaminant mixtures and offer recommendations on which types of agrochemicals to apply together and separately to reduce their impacts on aquatic ecosystems.
I extended this framework to test if the direct effects of pesticides can be predicted by chemical class and/or mode of action. I performed standard toxicity trials on two invertebrate predators of snails (crayfish and giant water bugs) exposed to six insecticides belonging to two chemical classes (organophosphates and pyrethroids) to determine if environmental risk can be generalized to either insecticide class or insecticide exposure. Survival analyses demonstrated that insecticide class accounted for 55.7% and 91.1% of explained variance in crayfish and water bug survival, respectively. Simulated environmental exposures using US EPA software suggested that organophosphate insecticides present relatively low risk (as defined by the US EPA) to both crayfish and water bugs, while pyrethroid insecticides present consistently high risk to crayfish but not to water bugs, where only λ-cyhalothrin produced consistently high-risk exposure scenarios. Thus, risk to non-target organisms is well predicted by pesticide class. Furthermore, identifying insecticides that pose low risk to aquatic macroarthropods might help meet increased demands for food while mitigating against potential negative effects on ecosystem functions.
Because evidence from field data and manipulated experiments demonstrated both top-down and bottom-up effects of agrochemical pollution that increased snail densities and trematode infections in wildlife, I conducted an additional agrochemical mixture experiment with freshwater communities containing the snail hosts of schistosomiasis, which has also been linked to agriculture. As expected, top-down and bottom-up effects of insecticide, herbicide, and fertilizer exposure indirectly increased snail densities, individually and as mixtures. Agrochemical exposure and snail density together accounted for 88% of the variation in the density of infected snails. Thus, agrochemical pollution has great potential to increase human exposure to schistosome parasites, and underscores the importance of identifying low-risk alternative pesticides. A subsequent mesocosm experiment with the same six insecticides used previously in laboratory trials confirmed that insecticide exposure indirectly mediates the densities of snail hosts that can transmit schistosomiasis through the direct effects of insecticides on crayfish mortality. Importantly, crayfish mortality in semi-natural mesocosm trials closely matched mortality from controlled laboratory trials. Thus, standard laboratory toxicity tests can be a useful tool for identifying alternative insecticides that might pose lower environmental risks to important predators that regulate snail densities.
Identifying practices or agrochemicals that minimize this risk is critical to sustainably improving human health in schistosome-endemic regions. The theoretical framework presented here demonstrates the feasibility of predicting the effects of contaminant mixtures and highlights consistent effects of major agrochemical types (e.g. fertilizers, insecticides, etc.) on freshwater aquatic community composition. Furthermore, the strong top-down effects of invertebrate snail predators highlight that managing for high snail predator densities in might be a particularly effective strategy for reducing the burden of schistosomiasis in tropical countries.
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Miserendino, Rebecca Adler. "Tracing mercury pollution in aquatic ecosystems| Implications for public health." Thesis, The Johns Hopkins University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3571745.
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This dissertation addressed questions pertaining to mercury (Hg) fate and transport in aquatic ecosystems by applying stable Hg isotopes as a tracer. Mercury poses a public health burden worldwide. In parts of the developing world, Hg-use during artisanal and small-scale gold mining (ASGM) is pointed at as the source of elevated Hg in the environment. However, Hg from other sources including soil erosion associated with land cover and land-use change (LCLUC) may also contribute to local Hg pollution.
Stable Hg isotope profiles of sediment cores, surface sediments, and soils from two aquatic ecosystems in Amapá, Brazil, one downstream artisanal gold mining (AGM) and one isolated from AGM were assessed. Although previous studies attributed elevated environmental Hg levels in this area to AGM, stable Hg isotopic evidence suggests elevated Hg downstream of AGM sites is dominantly from erosion of soils due to LCLUC.
In contrast, the impact of Hg-use during small-scale gold mining (SGM) in the Southern Andean Region of Portovelo-Zaruma, Ecuador on Hg in the trans-boundary Puyango-Tumbes River was also investigated. By comparing preliminary isotopic Hg signatures from river sediment along the Puyango-Tumbes to soil and sediment from upstream locations along the Puyango tributaries, we suggest Hg-use during SGM in this region is likely responsible for elevated Hg downstream and into Peru. Technical and policy challenges in measuring and responding to gold mining-related cumulative impacts were also reviewed in the context of Portovelo-Ecuador.
Together, the findings not only answer questions of critical importance to preventing Hg pollution in two of the world's most vulnerable ecosystems but also provide information that can be used to better target interventions to reduce environmental Hg levels and subsequent human exposures. Furthermore, the validation and application of the stable Hg isotope method to trace Hg pollution from ASGM in different aquatic ecosystems represents a critical step to the application of stable Hg isotopes to trace pollution in other complex natural environments and to address public health-related questions.
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Murphy, Fionn. "Microplastic pollution in the aquatic environment : sources, destination & effects." Thesis, University of the West of Scotland, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.736949.
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Microplastic are plastics that are < 5mm and is a contaminant of emerging concern in the aquatic environment. They are produced to be of a microscopic size or are created through the fragmentation of larger plastic material due to degradation. Microplastic has been found to be ubiquitous in the marine and freshwater environment with shoreline and deep sea sediment, oceans, rivers and lakes throughout the world observed to be polluted by microplastic. Wild populations of aquatic biota with various feeding behaviour have been observed to ingest microplastic. Exposure studies have also demonstrated the harmful effects of microplastic on a range of aquatic organisms. In this thesis, various aspects of microplastic pollution were investigated, from the sources of microplastic in the environment, to the destination of the microplastic once it enters the environment as well as the potential effects of microplastic on exposed organisms. The contribution a wastewater treatment works (WwTW) is making to microplastic pollution in the environment was estimated and the extraction efficiency of microplastic within the treatment process was determined. This study identified the key parts of microplastic removal in the treatment process. Aquaculture was also investigated as a source of microplastic in the environment by comparing synthetic rope and netting used in the industry with microplastic extracted from cultured fish and wild shellfish. The ingestion of microplastic by a variety of fish species sampled from Scottish marine waters were investigated finding considerably higher ingestion rates in demersal flatfish sampled from coastal waters then species sampled further offshore in much deeper waters. The effects of microplastic were investigate by developing a novel bioassay to measure ecologically relevant endpoints such as feeding and reproduction as well as morphology in Hydra attenuata exposed to microplastic. Hydra attenuata feeding was found to decrease as microplastic concentration increased. This work shows that microplastic is ubiquitous throughout the aquatic environment and can potentially effect exposed organisms.
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Campbell, Andrew Thomas. "Some aspects of the aquatic and analytical chemistry of antimony and arsenic." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357182.
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Andrews, Stephanie Beth. "Heavy Metal Pollution in the Nu'uanu Watershed: Aquatic and Roadside Sediments." Thesis, University of Hawaii at Manoa, 2002. http://hdl.handle.net/10125/7057.
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Previous research on Honolulu streams indicates that contamination by trace metals from automobile usage is a significant problem, especially Cu (copper), Pb (lead), and Zn (zinc). Therefore, this study was designed to determine the influence of road sediments and storm sewers on bioavailable trace metal concentrations in bed sediments of Nuʻuanu Stream, Oʻahu. Enrichment ratios (ERs) indicated that the Nuʻuanu watershed is significantly polluted in the lower, urbanized reaches, with maximum ER values of 444 (road sediments) and 74 (stream sediments) for Pb. Median ER values for Cu, Pb, and Zn in stream sediments were calculated as 2.0, 28.3, and 4.6, respectively. Considering the lack of industrial centers in the Hawaiian Islands, the Nuʻuanu watershed has extremely high levels of Pb, with a maximum value of 332 mg/kg and 3140 mg/kg in stream and road samples.ix, 108 leaves
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Ebrahimi, Mansour. "Effects of pollution on steroidogenesis and sperm in fish." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389736.
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Reinhold, Dawn Marie. "Fate of fluorinated organic pollutants in aquatic plant systems studies with lemnaceae and lemnaceae tissue cultures /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/26506.
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Thesis (Ph.D)--Civil and Environmental Engineering, Georgia Institute of Technology, 2008.Committee Chair: Saunders, F. Michael; Committee Member: Huang, Ching-Hua; Committee Member: Hughes, Joseph; Committee Member: Loeffler, Frank; Committee Member: Pullman, Gerald; Committee Member: Spain, Jim. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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de, Souza Machado Anderson Abel. "Coastal pollution of aquatic systems : literature review and experiments focusing on metal fate on estuaries." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24637.
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Anthropocene is the current era in which human activities modify various environmental properties, which have implications for many coastal processes. Anthropogenic stressors increasingly affect coasts and push these environments to a new altered equilibrium state. However, monitoring such pollution is a challenging task because coastal systems are highly dynamic and integrate the physicochemical forces at work on freshwater bodies, estuaries and lagoons with the oceanographic characteristics of adjacent seas. The current thesis addresses pollution of coastal environments in a broad way, with special attention to the current and historic problematic of estuarine contamination by metals. Firstly, it introduces the chemical (e.g. metals, persistent organic pollutants, and emerging contaminants), physical (e.g. microplastics, sediment loads, temperature), and biological (e.g. microbiological contamination, invasive species) pervasive anthropogenic influence in coastal areas. This introductory chapter is followed by a discussion on the limitations towards holistic environmental health assessments that are imposed by the scarcity of tools and multidisciplinary approaches. At that juncture, we perform a deep investigation of metal fate and its effects in estuaries. The review of the scientific literature in the third chapter provides a transdisciplinary conceptual framework for the estuarine behaviour of metals and its impacts on fauna and flora. This comprehensive overview and conceptual model are further accompanied by an elaboration on empirical models, as well as discussion of data on metal behaviour under laboratory and field conditions. While our review postulates that most studies had observed a non-conservative behaviour of metals in estuaries, our data suggests that at local scale such phenomenon is greatly explained by a high metal mobilisation driven by biogeochemical gradients. In fact, our results demonstrate that iron mobilisation regulates the pollution levels of iron and potentially other metals in an intertidal area under strong anthropogenic influence. In summary, estuarine physicochemical gradients, biogeochemical processes, and organism physiology are jointly coordinating the fate and potential effects of metals in estuaries, and both realistic model approaches and attempts to postulate site-specific water quality criteria or water/sediment standards must consider such interactions.
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Al-Omran, L. A. J. "The distribution and behaviour of phthalate esters in the aquatic environment." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382038.
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Slinger, Peter Gerard. "The effectiveness of local air pollution control in Lancashire." Thesis, University of Central Lancashire, 2002. http://clok.uclan.ac.uk/20646/.
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This thesis examines the implementation of air pollution control at the local level within the UK. Focusing upon the local air pollution control regime (LAPC) that is regulated by local authorities under the provisions of Part One of the Environmental Protection Act 1990, the research assesses whether this system has been effective in controlling localised emissions from industrial processes. To place the research in context, it essentially evaluates the implementation of LAPC with reference to its main objectives: to reduce industrial emissions and improve local air quality, to provide greater clarity and certainty for business and to allow the public greater access to local environmental information. The methodology adopted to undertake the research was based upon grounded theory and naturalistic inquiry. As such, the research programme was structured in phases where initially, essential baseline data was collected on the LAPC system. This quantitative data provided the foundations from which more detailed qualitative work was undertaken in the field in subsequent phases of the research. This allowed the research to build towards theory utilising an emergent, yet structured research design. As the research progressed, a range of complementary methods were used to collect data about the LAPC system. Initially, the research critically evaluated the major Reports that had been written on LAPC in order to establish benchmarks from which implementation of the LAPC system could be assessed. To keep the research within defined limits, a case study approach was adopted, using Lancashire as the case study area. Under the first phase of the research a questionnaire was used to survey the process operators within the region in order to collect baseline information about their processes and to obtain their views and perceptions of the LAPC system. Under the second phase qualitative research was carried out in the field. This involved detailed, semi-structured, faceto-face interviews with the process operators and the DETR and examination of documentary evidence within the Public Registers held by Lancashire's local authorities. The phased approach allowed the research to explore progressively deeper into the key areas associated with the implementation of the LAPC system. In particular, the research examined local authority enforcement and administration of the LAPC system to assess their regulatory performance and to determine the strategies they adopt to achieve compliance. The research also focused upon the process operators to assess their capacity to comply with the duties and responsibilities placed upon them under LAPC. The work offers a new perspective as it focuses upon both regulators and operators alike and examines their performance from the outset of LAPC to its closing stages. The research findings allow conclusions to be drawn on the relationship that exists between these "stakeholders" and the regulatory conditions that exist within the system. The research findings suggest that local authorities and process operators have had difficulty in discharging their duties under the LAPC system. For various reasons, the capacity of the regulators and the operators to achieve compliance has been compromised. The difficulties that the stakeholders have faced in striving to come to terms with the LAPC system have influenced their compliance strategies and affected the relationship that exists between them. This research identifies and examines these difficulties and assesses their performance under such conditions.
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Webb, Diane. "Assessment of the health of the Swan-Canning river system using biochemical markers of exposure of fish." Thesis, Curtin University, 2005. http://hdl.handle.net/20.500.11937/62.
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Most environmental studies concerning the environmental health of the Swan- Canning River system have focussed on nutrient inputs from both rural and urban catchments that are the cause of algal blooms. On occasions these algal blooms have resulted in fish deaths attributed to oxygen starvation. Relatively few studies have examined whether non-nutrient contamination is affecting the health of the riverine environment. Those studies that have, have concentrated on measuring the levels of heavy metals, organochlorines, organophosphates, and hydrocarbons in the sediments and water of the river system, and in the flesh of the biota. However, chemical analysis often fails to detect chemicals of concern due to high laboratory detection limits. In addition, analysis of the body burden of contaminants within biota does not necessarily convey if exposure is inducing adverse effects at the individual or ecosystem levels. The use of biochemical markers as a tool for the assessment of the health of the Swan-Canning River system was examined under a collaborative research project with the Waters and Rivers Commission, established in response to the recognition of the paucity of information from chemical analyses. The present study focussed on the estuarine portion of the Swan-Canning River system, using the black bream (Acanthopagrus butcheri), an estuarine dependent fish species, as a biomonitoring tool. Prior to the commencement of this study it had been determined that the black bream was a suitable fish species for use as a biomonitoring tool when using mixed function oxygenase (MFO) activity induction under laboratory conditions.Biopsies taken from feral black bream collected from eight sites during the period 2000 to 2002 from the estuary confirmed that the use of MFO induction in this fish species as a biomarker of exposure to organic contaminants is a reliable biomarker. Fish gender was a confounding factor in the interpretation of MFO induction when using the enzyme ethoxyresorufin-O-deethylase (EROD) as EROD activity was suppressed in both pre- and post-spawning female black bream. No such suppression was identified when using the MFO enzyme ethoxycoumarin-O-deethylase (ECOD). However, due to differences in the pattern and intensity of the induction of EROD and ECOD activities it was concluded that ECOD activity was not a substitute for EROD activity to detect certain chemical as ECOD activity represents a different cytochrome P450 pattern to EROD activity. No spatial, seasonal or interannual differences in the level of the enzyme sorbitol dehydrogenase (SDH) in the blood of the black bream were measured indicating that the interpretation of MFO activity induction was not compromised by hepatocellular damage. This study has shown that the black bream in the Swan-Canning Estuary are exposed to, and are metabolising polycyclic aromatic hydrocarbons (PAHs), notwithstanding that the chemical analysis of the contaminant load of these substances in the estuarine waters is consistently below laboratory detection limits. In addition, biomarker responses such as ECOD activity indicate that various other organic pollutants are present and are being metabolised by the black bream.The measurement of biliary metabolites clearly show that, under winter conditions, the comprehensive drainage system of the Swan Coastal Plain contributes PAHs from pyrogenic sources such as burnt fuels into the estuary although the onset and intensity of rainfall events notably impacts on the volume of stormwater inflow. During the summer months, when freshwater flow is minimal, petrogenic sources of PAHs are dominant. Metabolic enzyme analysis points to the black bream being challenged in their aerobic capacities during summer, and that gill tissue was the most suitable tissue to evaluate the aerobic and anaerobic capacity of this fish species. Furthermore, there was a significant negative correlation between stress protein (hsp70) expression and DNA integrity in field-collected fish suggesting that the black bream within the estuary are highly stressed. No gradient of response in biomarker levels was identified in the Swan-Canning Estuary under either winter or summer conditions indicating there are multiple sources of inputs of potential pollutants along the length of the estuary. Stormwater and road runoff are the primary source of pollutant input into the estuary in the winter months, while summer biomarker levels, particularly PAH, appear to reflect the high usage of the estuary for recreational purposes and runoff from poorly irrigated parks and gardens. Significant rainfall events at any time of the year have the potential to adversely impact the biota of the estuary, particularly when these events result in a flush of water from the drains following long dry periods.The study shows that the black bream is a suitable fish species to use under field conditions to detect the presence of bioavailable non-nutrient contamination within the Swan-Canning Estuary. A suite of biomarkers in black bream have been tested seasonally and annually but only a small number of biomarkers have proven suitable for routine monitoring of the health of the Swan-Canning Estuary. This treatise concludes with several recommendations for further investigations into biomarkers of fish health for the purpose of increasing our understanding on the sources and type of contamination entering the estuary, and potential effects on the aquatic biota of the Swan-Canning River system. These recommendations include, but are not limited to: (1) the need to determine baseline levels for the different biomarkers investigated in this study, (2) the examination of the Moore River or the Warren River estuaries as potential reference sites for biomarker studies in the Swan- Canning Estuary, (3) the advantage of identifying a second estuarine-dependent indigenous fish as a biomonitoring tool, (4) the requirement for a targeted study aimed at clarifying the relationship between major drain discharges, biomarker levels and impacts on river biota, and (5) a study of estuarine waters utilising SPMDs be undertaken in tandem with biomarker analysis of field captured fish would be beneficial.
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Nuttall, Charlotte A. "Aquatic zinc pollution from abandoned mines : assessment and passive treatment in the Nent Valley, Cumbria, UK." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314092.
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Chi, Siu-chung, and 池少翀. "Eco-toxicity of antibiotics on aquatic organism." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43783600.
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Cullen, Daniel W. "Genetic location and transferability of chromium resistance gene(s) among aquatic bacteria." Thesis, Glasgow Caledonian University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339325.
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Chiu, Hok-cheung Simon, and 周鶴祥. "The use of bacteria to monitor and reflect pollution of the aquatic environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210740.
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Ullrich, Susanne Maria. "Industrial mercury pollution with particular emphasis on its impact in the aquatic environment." Thesis, University of Southampton, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438710.
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Snyder, Craig David. "Physiological, population, and genetic responses of an aquatic insect (Isonychia bicolor) to chronic mercury pollution." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165554/.
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Ansa-Asare, Osmund Duodu. "Do diurnal dissolved oxygen cycles have diagnostic value for assessing pollution status in lakes?" Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285509.
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The effects of pollutant burdens on natural cyclic patterns in aquatic ecosystems have been studied, to test the hypothesis that a parameter or parameters describing the pattern of variation in a single determinant, such as DO or pH, may be used to describe the status of a body of water more meaningfully than results from single spot measurements. In this study the background water quality in a Scottish and a Ghanaian lake was assessed, then rafts were built on the lakes (Myrtle Dam and Weija Lake respectively) creating three small lakes to test the effects of pollutant loads (e.g. organics and nutrients) on them. Laboratory investigations to study the behaviour of the pollutants on DO or pH cycles were carried out, and then a dynamic DO model was developed to describe the cyclic behaviour of DO. Finally, the model was used to investigate the effects of added pollutant burdens on the DO cycles. Water quality assessment of Myrtle Dam and Weija Lake by using the Weighted Water Quality Index proved that Weija Lake has doubtful quality with WQI 51, which needs improvement. Myrtle Dam WQI of 73 shows that the lake waters are unpolluted (or recovered from pollution). It is also well oxygenated at the surface and receives no toxic discharge. The raft experiments for Myrtle Dam and the Weija Lake have been used to demonstrate that, in the raft tubes, organic loadings do have effects on the oxygen cycles, and showed that there are two effects. One is that, with a small organic loading, the mean DO value dropped, then increased as the organic loading was consumed. The second is that the amplitude of the DO cycle increased as the organic loading increased from 2.5 to 5.0 mg L-1 TOC for Myrtle Dam, and decreased for Weija Lake as the organic loading increased from 2.5 to 5.0 mg L-1 TOC. The laboratory experiments in both Ghana and Aberdeen proved to be useful in explaining the effects of nutrients and trace elements on the DO cycles. It was evident that the higher the algal concentration, the greater was the DO cycle and 30% v/v (c.a. 254 mg L-1 chlorophyll 'a' content ≍ 17 g L-1 biomass aqueous algal suspension) proved to be the most suitable concentration for investigations, because, with higher organic loadings, the 100% aqueous algal suspension proved to be too concentrated and caused total deoxygenation.
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Comber, Sean David William. "The biochemical control of arsenic in certain estuaries." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280907.
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Astley, Katrina Nicola. "The ecotoxicological assessment of complex effluents using invertebrate biomarkers." Thesis, University of Plymouth, 1998. http://hdl.handle.net/10026.1/2024.
Full textAbstract:
A suite of biomarkers was developed using the crab Carcinus maenas and the mussel Mytilus edulis as test organisms. The ability of the biomarkers to differentiate amongst the major toxic components and to indicate the concentration of chemical mixtures was evaluated in the laboratory. Biomarkers were also applied in a field trial and their potential to monitor environmental water quality in a chemically contaminated estuary investigated. The results from the biomarker assays were compared with and validated against two commonly used toxicity tests (Tisbe battagliai LC-50, and Microtox®). Novel methods for recognising patterns of biomarker responses were developed and assessed. The most sensitive and reliable biomarker assays investigated were neutral red retention time in crabs and mussels and heart rate and glutathione-S-transferase activity in crabs. Effects were observed at environmentally realistic concentrations; for example lysosomal enlargement was observed in mussels exposed to a complex mixture containing chemicals at environmental quality standard concentrations. Exposure concentrations required to illicit biomarker responses were similar to toxicity test EC-50 values. The ease of interpretation and clarity of the results was enhanced when data from suites of biomarkers were pooled and analysed using multivariate statistical techniques (multidimensional scaling and cluster analysis). Multivariate analysis differentiated amongst mixtures containing solely organic chemicals, metals and metal and organic chemical mixtures. Exposure response relationships to complex mixtures were established for some of the individual biomarkers tested (crab heart rate and gill metallothionein) and also for suites of biomarkers when multivariate analysis was carried out. In the field biomarkers, in both transplanted and indigenous animals, were able to differentiate between clean and contaminated sites and indicate a pollution gradient along the Tees Estuary. This was not achieved using toxicity tests. The results were displayed clearly using multivariate analysis, enhancing the power of biomarkers as monitoring tools.
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Tront, Jacqueline Marie. "Plant Activity and Organic Contaminant Processing by Aquatic Plants." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5234.
Full textAbstract:
This research explored fate of organic contaminants in aquatic plant systems through (i) experimental development of relationships to describe sorption, uptake and enzymatic processing of contaminants by plants and inhibition of aquatic plants by contaminants and (ii) incorporation of experimental relationships into a conceptual model which describes contaminant fate in aquatic plant systems. This study focused on interactions of aquatic plants L. minor and M. aquaticum with halogenated phenols. 2,4,5-trichlorophenol (2,4,5-TCP) and 2,4-dichlorophenol (2,4-DCP) are precursors for the highly toxic and heavily applied herbicides 2,4,5-T and 2,4-D and were examined in detail. Chlorophenols are generally resistant to microbial degradation, a property which may limit microbial remediation options as effective alternatives for clean up of contaminated sites.
Relationships for fundamental interactions between plants and contaminants that dictate uptake, enzymatic processing and sequestration of contaminants by aquatic plants were established. An assay which quantified production of oxygen by plants was developed to quantify plant metabolic activity and inhibition. Uptake of chlorinated phenols depended on plant activity and aqueous phase concentration of contaminant in the protonated form. Therefore, plant activity, contaminant pKa and media pH were established as critical parameters controlling rate of contaminant uptake. A conceptual model was developed which incorporated plant activity and inhibition into a mathematical description of uptake of organic contaminants by aquatic plants. The conceptual model was parameterized using experimental data delineating effect of plant activity, inhibition and speciation on contaminant uptake and the model was verified using independently gathered data. Experimentation with radio-labeled chlorinated phenols established that contaminants were sequestered internal to plants by plant enzymatic processing. 19F NMR was established as a technique to quantify transformation and conjugation products internal to plants and contaminant assimilation by plants and demonstrated that multiple metabolites containing the parent compound were present and quantifiable internal to plants. Finally, fate of plant-sequestered contaminants in an anaerobic bioassay was examined using Desulfitobacterium sp. strain Viet1.
The results of this study address the role of aquatic plants in sequestration of contaminants in surface waters that indicate the potential and limitations of use of aquatic plants in natural and engineered treatment systems.
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Hughes, Mary Siobhan. "A study of the aquatic environment in Northern Ireland for the presence of human enteroviruses in relation to public health." Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335411.
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White, Jessica C. "Comparative Bioavailability of Dietary and Dissolved Cadmium to Freshwater Aquatic Snails." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4351/.
Full textAbstract:
Heavy metal bioaccumulation in aquatic organisms may occur through direct or indirect uptake routes. Research indicates that the significance of uptake route varies with contaminant and organism exposed. The relative importance of different metal sources in aquatic systems was investigated by exposing freshwater snails to dietary or dissolved sources of cadmium. Snails were exposed to control, contaminated food only, contaminated water only, and contaminated food and water treatments. During the 15-day exposure, samples were taken to determine Cd concentration in snail soft tissue, snail shell, algal food, and overlying water. Analyses of snail soft tissue and shells indicate that exposure route significantly affects Cd concentrations in the tissues. In both cases, dissolved Cd is the primary contributor to metal body burden.
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Leeming, Rhys, and n/a. "Coprostanol and related sterols as tracers for feacal contamination in Australian aquatic environments." University of Canberra. School of Resource, Environmental & Heritage Sciences, 1996. http://erl.canberra.edu.au./public/adt-AUC20060816.172519.
Full textAbstract:
Pollution from human and animal faecal waste is a major cause of deteriorating water
quality and increased nutrient loads in coastal and inland waterways. Management of
this problem depends on knowing which sources of faecal matter are the cause and
what is the degree and extent of the pollution. Bacterial indicator organisms have long
been the principal method used to test water samples for faecal contamination.
However, none of the currently used bacterial indicators on their own are source
specific enough to distinguish different sources of faecal matter. The use of faecal
sterol biomarkers in conjunction with existing bacterial indicators offers a new way to
distinguish sources of faecal contamination.
This study investigates the sources of faecal sterols, the relationship of coprostanol to
existing bacterial indicators of faecal pollution, the degradation of faecal sterols and the
problem of determining the sources of faecal contamination and the distribution of
faecal contamination using faecal sterol biomarkers. 5p-Stanols (i.e. faecal sterols)
were found to be significant constituents of human, herbivore (i.e. cows, sheep etc.)
and pig and cat faeces. Human faeces contained 73 ± 4% coprostanol in relation to
the sum of coprostanol and 24-ethylcoprostanol and primary treated effluent contained
86 ± 0.4% coprostanol. Herbivore faeces contained 38 ± 4% coprostanol and 62 ±
4% 24-ethylcoprostanol whereas pig faeces contained 50 � 5% of each compound.
Both birds and dogs faeces contained either trace amounts of 5B-stanols or they could
not be detected. Notable differences were observed in the abundance of Closthdium
perfringens spores between the faeces of birds and domestic pets such as cats and
dogs. The above differences were subsequently exploited to distinguish faecal
contamination in Lake Tuggerah. An examination of the relationships between
coprostanol and bacterial indicator concentrations from several environments revealed
that 60 and 400 ng L of coprostanol corresponded to currently defined primary and
secondary contact limits for bacteria measured as either thermotolerant coliforms or
enterococci in the environment.
Four degradation experiments showed faecal sterols and related sterols such as
cholesterol decay at similar rates. An induction period was observed in all
experiments which meant that simple exponential equations to describe the rate of
decay of coprostanol were inadequate; a complimentary log - log transformation of the
data was used and the equation:
Y = l-Exp(-Exp(time x -0.01 + temp x -0.158 + 3.33)) x 100
was derived where Y equals the predicted percentage of coprostanol remaining over
time at a given temperature. In terms of persistence in the environment, Clostridium
perfringens spores > coprostanol > enterococci > thermotolerant coliforms.
Two field studies were undertaken to highlight the use of faecal sterols. In the Lake
Tuggerah study, the results indicated that faecal contamination of receiving waters in
the Tuggerah Lakes during rain events was significant, but was not derived from
human faecal matter; rather it appears to be principally derived from native birds and,
to a lesser extent, domestic pets. In the Derwent Estuary study, based on the
distribution of the faecal biomarker coprostanol, the mid estuary and parts of the upper
estuary (from Newtown Bay to Taroona), were found to be severely contaminated by
sewage. In summary, the use of faecal sterols to trace faecal contamination were found
to be an invaluable addition to the tools water managers use to investigate faecal
pollution.
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Carr, Stephen Thomas David. "Investigation into phosphorus removal by iron ochre for the potential treatment of aquatic phosphorus pollution." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7663.
Full textAbstract:
Phosphorus (P) pollution of waterbodies is a global issue with detrimental environmental, social and economic impacts. Low-cost and sustainable P removal technologies are therefore required to tackle P pollution, whilst also offering a technique for reclaiming P. Ochre, a waste product from minewater treatment plants (MWTPs), has been proposed as a suitable material for the removal of P from enriched waters due to a high content of Fe, Al, Ca and Mg, which have high affinities for P removal. Whilst a range of studies have been conducted investigating ochre as a P adsorbent, most of these are large-scale field experiments and lack understanding of the underlying processes of P removal by ochre. There have also been very few detailed comparisons of different ochre types. The primary focus of this thesis is thus to provide a process-based understanding of P removal by various ochres, in order to investigate the optimal conditions for the use of ochres in the treatment of aquatic P pollution. Seven ochres from six MWTPs in the UK and Ireland were investigated, one of which was in a pelleted form. The ochres were largely comprised of Al, Ca, Fe and Mg (42-68 % by dry weight), had a high B.E.T. surface area, 56-243 m2 g-1, and contained mineral surfaces with a high affinity for P adsorption, such as goethite and calcite. A novel batch experiment methodology was utilised to calculate the adsorption characteristics of ochre at discrete pH conditions. The variation of these characteristics with pH indicates the importance and requirement for such a method to study adsorption by materials at the expected pH conditions of application. At the pH conditions of wastewater streams (~pH 7), the P adsorption capacities of the ochres, determined from fitting adsorption isotherms, was 11.8–43.1 mg P g-1. Results of P adsorption batch experiments were modelled in ORCHESTRA, wherein P removal by the ochres was described well by adsorption onto hydrous ferric oxides. Three of the ochres contain relatively high calcite contents and due to a poor fit of the model to the observed datasets at high pH conditions, with equilibrium P concentrations lower in the batch experiments than the modelled result, adsorption onto calcite is suggested as a P removal mechanism for these ochres at pH > 7. Environmental application of ochre filters will require P removal under flow-through transport conditions. Column experiments were therefore conducted using two ochres, coarse-grained Polkemmet ochre and Acomb pellets (column volume 1055 cm3, pore space 490-661 cm3, typical pore volumes of experiments: 220-400). P removal efficiency increased with contact time, and the presence of competing ions had only marginal effects on P removal. Resting the column substrate for 48 hours between P applications greatly increased the P removal efficiency of a packed column of Polkemmet ochre, resulting in 81 % of influent P removed over 1000 pore volumes of operation (7.68 mg P g-1). Acomb pellets had a lower P removal efficiency than Polkemmet ochre. It is suggested that the high calcium content of the pellets, as a result of the pelletisation process, has created a substrate where the dominant P removal mechanism at neutral pH conditions is adsorption to calcite, which has slower reaction kinetics than adsorption onto goethite. Therefore, this pelleted ochre requires a higher contact time for adsorption reactions to occur. It is suggested that ochre filters are most suitable for application in situations where flow rate is constant or can be controlled e.g. septic tank effluent. Ochres which dry to a coarse particle size are preferred for use as a substrate as pelletisation requires capital, expertise and can produce substrates with slower P sorption kinetics. Resting the filter substrate between P application regenerates surface sites for adsorption, and filters should be run in parallel to maximise P removal efficiency. Acomb pellets, which are a mix of iron hydroxides and alkaline materials, may have potential application as a permeable reactive barrier substrate to treat P enriched ground waters. Further research utilising fine-grained ochres as an additive to P rich fertilisers or for use in continuously stirred tank reactors is recommended.
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Nwabineli, Betty Ivie. "A macro and micro study of the impact of sewage discharges to aquatic environments close to human habitats." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311990.
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Колмикова, Аліна Ігорівна. "Prospects for reducing the impact of phosphates on aquatic ecosystems." Thesis, Національний авіаційний університет, 2020. http://er.nau.edu.ua/handle/NAU/43595.
Full textAbstract:
Робота публікується згідно наказу ректора від 21.01.2020 р. №008/од "Про перевірку кваліфікаційних робіт на академічний плогіат у 2019-2020 навчальному році". Керівник проекту: доцент кафедри екології, к.б.н., Білик Тетяна ІванівнаThe object of research is the pollution of aquatic ecosystems with phosphates. The subject of research is the reduction of the impact of phosphates on aquatic ecosystems due to the improvement of wastewater treatment systems. The aim of the work was to analyze the prospects for reducing water pollution by phosphates and their impact on aquatic ecosystems due to the improvement of wastewater treatment system. Research methods: analytical, chemical, statistical methods of data processing. Relevance. In recent years, the amount of phosphates in the wastewater entering the treatment facilities of the city of Kyiv - Bortnytsia aeration station, has increased significantly. To date, it reaches almost 30 mg / l, with a standard discharge 8.0 mg / l. At this concentration of phosphates in the incoming water, the old treatment technologies do not allow to reach the established norms for wastewater, which causes eutrophication and death of aquatic organisms. The solution to this problem is to improve wastewater treatment systems and limit the use of phosphorus-containing detergents. Scientific novelty: an analysis of ways to reduce the impact of phosphates on aquatic ecosystems. Practical significance: the results of the study are prepared for implementation in a comprehensive program aimed at protecting aquatic ecosystems and reducing the content of phosphates in water bodies of Ukraine. Personal contribution of the author: elaboration of scientific literature on the topic of work, analysis of data of the Institute of Hydrobiology of the National Academy of Sciences of Ukraine and Kyivvodokanal, preparation for the implementation of research results.
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Webb, Diane. "Assessment of the health of the Swan-Canning river system using biochemical markers of exposure of fish." Curtin University of Technology, Department of Environmental Biology, 2005. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16725.
Full textAbstract:
Most environmental studies concerning the environmental health of the Swan- Canning River system have focussed on nutrient inputs from both rural and urban catchments that are the cause of algal blooms. On occasions these algal blooms have resulted in fish deaths attributed to oxygen starvation. Relatively few studies have examined whether non-nutrient contamination is affecting the health of the riverine environment. Those studies that have, have concentrated on measuring the levels of heavy metals, organochlorines, organophosphates, and hydrocarbons in the sediments and water of the river system, and in the flesh of the biota. However, chemical analysis often fails to detect chemicals of concern due to high laboratory detection limits. In addition, analysis of the body burden of contaminants within biota does not necessarily convey if exposure is inducing adverse effects at the individual or ecosystem levels. The use of biochemical markers as a tool for the assessment of the health of the Swan-Canning River system was examined under a collaborative research project with the Waters and Rivers Commission, established in response to the recognition of the paucity of information from chemical analyses. The present study focussed on the estuarine portion of the Swan-Canning River system, using the black bream (Acanthopagrus butcheri), an estuarine dependent fish species, as a biomonitoring tool. Prior to the commencement of this study it had been determined that the black bream was a suitable fish species for use as a biomonitoring tool when using mixed function oxygenase (MFO) activity induction under laboratory conditions.Biopsies taken from feral black bream collected from eight sites during the period 2000 to 2002 from the estuary confirmed that the use of MFO induction in this fish species as a biomarker of exposure to organic contaminants is a reliable biomarker. Fish gender was a confounding factor in the interpretation of MFO induction when using the enzyme ethoxyresorufin-O-deethylase (EROD) as EROD activity was suppressed in both pre- and post-spawning female black bream. No such suppression was identified when using the MFO enzyme ethoxycoumarin-O-deethylase (ECOD). However, due to differences in the pattern and intensity of the induction of EROD and ECOD activities it was concluded that ECOD activity was not a substitute for EROD activity to detect certain chemical as ECOD activity represents a different cytochrome P450 pattern to EROD activity. No spatial, seasonal or interannual differences in the level of the enzyme sorbitol dehydrogenase (SDH) in the blood of the black bream were measured indicating that the interpretation of MFO activity induction was not compromised by hepatocellular damage. This study has shown that the black bream in the Swan-Canning Estuary are exposed to, and are metabolising polycyclic aromatic hydrocarbons (PAHs), notwithstanding that the chemical analysis of the contaminant load of these substances in the estuarine waters is consistently below laboratory detection limits. In addition, biomarker responses such as ECOD activity indicate that various other organic pollutants are present and are being metabolised by the black bream.
The measurement of biliary metabolites clearly show that, under winter conditions, the comprehensive drainage system of the Swan Coastal Plain contributes PAHs from pyrogenic sources such as burnt fuels into the estuary although the onset and intensity of rainfall events notably impacts on the volume of stormwater inflow. During the summer months, when freshwater flow is minimal, petrogenic sources of PAHs are dominant. Metabolic enzyme analysis points to the black bream being challenged in their aerobic capacities during summer, and that gill tissue was the most suitable tissue to evaluate the aerobic and anaerobic capacity of this fish species. Furthermore, there was a significant negative correlation between stress protein (hsp70) expression and DNA integrity in field-collected fish suggesting that the black bream within the estuary are highly stressed. No gradient of response in biomarker levels was identified in the Swan-Canning Estuary under either winter or summer conditions indicating there are multiple sources of inputs of potential pollutants along the length of the estuary. Stormwater and road runoff are the primary source of pollutant input into the estuary in the winter months, while summer biomarker levels, particularly PAH, appear to reflect the high usage of the estuary for recreational purposes and runoff from poorly irrigated parks and gardens. Significant rainfall events at any time of the year have the potential to adversely impact the biota of the estuary, particularly when these events result in a flush of water from the drains following long dry periods.
The study shows that the black bream is a suitable fish species to use under field conditions to detect the presence of bioavailable non-nutrient contamination within the Swan-Canning Estuary. A suite of biomarkers in black bream have been tested seasonally and annually but only a small number of biomarkers have proven suitable for routine monitoring of the health of the Swan-Canning Estuary. This treatise concludes with several recommendations for further investigations into biomarkers of fish health for the purpose of increasing our understanding on the sources and type of contamination entering the estuary, and potential effects on the aquatic biota of the Swan-Canning River system. These recommendations include, but are not limited to: (1) the need to determine baseline levels for the different biomarkers investigated in this study, (2) the examination of the Moore River or the Warren River estuaries as potential reference sites for biomarker studies in the Swan- Canning Estuary, (3) the advantage of identifying a second estuarine-dependent indigenous fish as a biomonitoring tool, (4) the requirement for a targeted study aimed at clarifying the relationship between major drain discharges, biomarker levels and impacts on river biota, and (5) a study of estuarine waters utilising SPMDs be undertaken in tandem with biomarker analysis of field captured fish would be beneficial.
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Shang, Zhaorong. "A study of Ag-110m in aquatic and terrestrial ecosystems and the development of a radioecological model /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23768782.
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Toczydlowski, David G. "Aquatic microbial community responses to stress: comparison of nontaxonomic and taxonomic indices." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45672.
Full textAbstract:
Three nontaxonomic indices; ATP/Chlorophyll a(ATP/Chla),
ATP/ADP, and Chlorophyll a/Pheopigment (Chla/Pheo) were compared
to the taxonomic measures of species diversity (d) and species
richness as indicators of stress in aquatic environments. Field
and laboratory microcosm responses of indigenous microbial
communities exposed to municipal sewage treatment plant (STP)
effluent were monitored. The STP effluent produced increased
adenylate concentrations, ATP/ADP and ATP/Chla ratios, and
decreased Chla, Chla/Pheo, d, and species richness relative to
upstream reference communities. Nontaxonomic responses were
consistent in four separate field tests.
Significant differences in responses were discernible in 3 d when communities were transferred from reference to polluted sites. Chla/Pheo decreased more rapidly than other measurements. The predictive capability of laboratory flowâ through microcosm tests was examined by simultaneously transferring communities from upstream reference sites to downstream field sites and to various dilutions of field effluent in the laboratory.
Master of Science
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Lahman, Sara Elisabeth. "The Ecotoxicological Impacts of Copper in Aquatic Systems." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1427119997.
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Green, Christopher. "Assessing the roles of anti-androgenic and oestrogenic mixtures on endocrine disruption in fish." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/10838.
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Incidence of endocrine disruption in wild fish species has been documented globally and is well characterised in the UK, where the occurrence of intersex in roach (Rutilus rutilus) is widespread. Although this has been associated with concentrations of steroid oestrogens, research indicates that anti-androgenic chemicals may also play a role in inducing these effects. Anti-androgenic activity is commonly detected in wastewater treatment works effluents and some receiving waters, but the chemicals responsible remain largely uncharacterised. This thesis aimed to identify environmental anti-androgens in UK and South Australian catchments and to produce environmentally relevant exposures to assess their potential impacts on sexual disruption in fish, alone and in combination with steroid oestrogens. By using hydrological modelling techniques, pharmaceuticals with an anti-androgenic mode of action were predicted to occur in the ng/L concentration range in UK and South Australian wastewater treatment works effluents and river catchments. This work included analysis of future trends in environmental concentrations of the pharmaceuticals and the steroid oestrogens in these catchments. Modest increases in concentrations by 2050 were predicted in the absence of mitigation, which could increase in the risk posed to fish health by the steroid oestrogens in the future. The effects of the predicted concentrations of two pharmaceuticals, bicalutamide and cyproterone acetate, were then assessed in fathead minnows (Pimephales promelas) and Japanese medaka (Oryzias latipes) based on the UK modelling for the present day. These concentrations did not contribute to endpoints characteristic of sexual disruption, alone or in combination with steroid oestrogens. However, the results did support an environmental role for the steroid oestrogens in intersex induction. Concurrently, effect directed analysis identified some highly potent anti-androgens, such as triclosan and pyrene, in wastewater treatment works effluents from the UK. However, they are likely to make a minor contribution to overall anti-androgenic activity due to their low concentrations. Consequently, more work is required to identify the causes of this activity in the environment and its implications for wild fish health.
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Fulton, Barry A. Brooks Bryan William. "Assessing interactions between nutrients and toxicity influences of nitrogen and phosphorus on triclosan toxicity to the aquatic macrophyte "lemna gibba" /." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5351.
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Subirats, Medina Jessica. "Influence of anthropogenic pollution on the prevalence, maintenance and spread of antibiotic resistance in aquatic microbial communities." Doctoral thesis, Universitat de Girona, 2018. http://hdl.handle.net/10803/664265.
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This Thesis demonstrates that microorganisms derived from wastewater are the
2/2
main contributors to antibiotic resistance (AR) in the environment. Once there, the background chemical contamination with antibiotic residues and other pharmaceutical compounds set the optimal conditions for the accumulation and spread of resistance genes among resident bacterial communities. We also prove that nutrients, in combination with emerging contaminants, act synergically on the dissemination of some antibiotic resistance genes (ARGs) within bacterial communities. According to our results, streambed biofilms appear as useful biosensors of the effect of wastewater discharges on the prevalence of AR in surface waters. Finally, we also proved that bacteriophages (viruses that infect bacteria) accumulate ARGs and thus they may have an important role on the dissemination of AR in aquatic environmentsLa present Tesi demostra que els microorganismes procedents de les aigües residuals són el principal factor implicat en distribuir la resistència als antibiòtics (AR) al medi natural i que la contaminació de fons per antibiòtics i altres fàrmacs estableix les condicions òptimes per la seva acumulació i disseminació entre les comunitats microbianes residents. També es demostra aquí que els nutrients, en combinació amb diferents contaminants emergents, actuen en sinergia per estimular la disseminació d'alguns gens de resistència als antibiòtics (ARGs) en les comunitats bacterianes. Segons els nostres resultats, els biofilms del llit fluvial esdevenen útils com a biosensors de l’efecte de les descàrregues d’aigües residuals en la prevalença de la AR en aigües superficials. Finalment, aquesta tesi també aporta resultats que proven que els bacteriòfags (virus que infecten bacteris) acumulen ARGs i, per tant, poden tenir un paper important en la disseminació de la AR en els ambients aquàtics
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COELHO, RICARDO dos S. "Avaliacao da qualidade da agua do corrego Franquinho, sub-bacia Tiquatira/Franquinho, unidade hidrografica do Alto Tiete, Sao Paulo, SP." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10920.
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Made available in DSpace on 2014-10-09T12:45:34Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:08:31Z (GMT). No. of bitstreams: 1 07157.pdf: 8474280 bytes, checksum: e1abd151fab0e19dd4d6f348fcc3f112 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Shang, Zhaorong, and 商照榮. "A study of Ag-110m in aquatic and terrestrial ecosystems and the development of a radioecological model." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B29747326.
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Meyer, Lars Alan. "In Light of Energy: Influences of Light Pollution on Linked Stream-Riparian Invertebrate Communities." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345479410.
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Arnolds, Judith Lize. "Oxidative stress responses in the aquatic macrophyte, Ceratophyllum Demersum L., as biomarkers of metal exposure." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2649.
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Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2017.Metal pollution in aquatic environments is considered a major environmental concern because of variation in several abiotic factors that impose severe restrictions on organisms living in these areas. Ceratophyllum demersum L. (family Ceratophyllaceae), a hornwort or coontail, free floating rootless macrophyte has been suggested a suitable model for investigating metal stress and was used in the current study. This study assessed the use of selected biological responses, namely antioxidant responses and changes in chlorophyll concentration in Ceratophyllum demersum L., as biomarkers of metal exposure, and also investigated the field application of these responses in the Diep River. The ultimate aim was also to determine the usefulness of C. demersum as model of metal contamination and as phytoremediator after a pollution event. An investigation of metal bioaccumulation in this macrophyte exposed to different concentrations of a combination of metals over a five-week exposure period in a greenhouse, was undertaken, as well as a field study in the Diep River, Milnerton, Cape Town and a pond (reference site) at the Cape Peninsula University of Technology, Cape Town, to validate experimental results. In the laboratory study the water was contaminated once off at the beginning of the study, to simulate a pollution event. The metal concentrations in the water and plants were measured in the four treatments and the control every week over a five-week exposure period. The samples were acid-digested and analysed with an Inductively-Coupled Plasma-Mass Spectrophotometer (ICP-MS). The results showed that concentrations of the metals in the water varied in all treatments over time with no specific patterns amongst the treatment groups. This macrophyte proved highly effective in the bioaccumulation of these metals at all four exposure concentrations. The metals bioaccumulated rapidly in the plants after the water was spiked. The main focus of the study was to investigate the possible use of biochemical responses in C. demersum as possible biomarkers for metal exposure. A range of antioxidant/oxidative stress parameters were measured in the plant exposed to a combination of metals (Al, Cu, Fe, Zn) in four different treatments over the five week exposure period. Total antioxidant capacity (TAC) was measured using Total Polyphenols (TP), Ferric Reducing Antioxidant Power (FRAP) and Oxygen Radical Absorbance Capacity assay (ORAC), enzyme activity was determined using Catalase (CAT), Superoxide Dismutase (SOD), Ascorbate Acid (AsA) and Total Glutathione (GSHt) and lipid peroxidation was measured by using Thiobarbituric Acid Reactive Substances (TBARS) and Conjugated Dienes (CDs). The cocktail of the four metals induced significant changes in the antioxidant defence system of C. demersum, including the antioxidant enzyme activities. The different metal exposures disturbed the cellular redox status in the plant. The current study has demonstrated that this macrophyte shows tolerance to metal-induced oxidative stress and that it can survive under relatively high concentrations of these metals by adapting its antioxidant defence strategies. Chlorophyll was extracted in 80% chilled acetone in the dark and the absorbance values were determined using a spectrophotometer. Chlorophyll a (chl a), chlorophyll b (chl b) and total chlorophyll (chl t) contents were measured under different exposure concentrations of metals in the macrophyte. The results of this study indicated that chlorophyll contents were variable over the exposure period and no significant differences in chlorophyll concentrations were found between weeks. A field study in the Diep River and the pond located at the CPUT campus (reference site) was conducted to validate experimental results. Plants in a polluted section of the Diep River were shown to bioaccumulate metals to high concentrations. Bioaccumulation of metals in C. demersum might have induced oxidative stress, and other environmental factors such as temperature- and chemical stress might have caused chlorophyll degradation. The chlorophyll concentrations in the plants of the pond (reference site) might also have been affected by temperature and chemical stress of the water. Significantly higher AsA, CAT, ORAC, SOD and TBARS concentrations in the Diep River plants might be an indication that the plants in the river might be well adapted to the constant exposure to metals and that the plants might have developed a tolerance mechanism to cope with oxidative stress compared to those of the pond. The results show that metals are bioaccumulated quickly by C. demersum after the water is contaminated with metals, i.e. after the "pollution event". However, over time, metals are continuously exchanged between the plants and the water, accounting for the fluctuations in metal concentrations observed over time. This study has shown that C. demersum has phytoremediation potential because it was able to remove high concentrations of metals from the contaminated water. Therefore, C. demersum, can be applied as a model for metal contamination and a phytoremediator after a pollution event. The potential to antioxidant responses and chlorophyll content as biomarkers of metal exposure in C. demersum have been demonstrated.
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Hum, Stanley. "Detection of latent heritable genetic damage in populations of aquatic snails, Lymnaea stagnalis, exposed in situ to genotoxic pollution." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0035/MQ64374.pdf.
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Hum, Stanley. "Detection of latent heritable genetic damage in populations of aquatic snails, Lymnaea stagnalis, exposed in situ to genotoxic pollution." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30670.
Full textAbstract:
We hypothesized that populations exposed to chronic levels of genotoxins for many generations in situ will accumulate latent heritable genetic damage leading to increases in mutational load and decreased population fitness. Common pulmonate snails (Lymnaea stagnalis) were collected from three sites that differed in pollution level [Manitoulin Island (reference), Beauharnois (moderate pollution), and Varennes (highly polluted)]. These organisms have a rapid generation time and are capable of self-fertilization. Fitness indicators were clutch size, survival (hatching to day 30) and growth (length from hatching to day 90). Recessive deleterious mutations that have accumulated through time are masked as snails preferentially outcrossed, but are expressed when snails self-fertilize. Results obtained by comparing fitness components of snails derived from selfing and outcrossing experiments showed that in sites with higher levels of pollution inbreeding depression increased for clutch size and survival. Results for growth rate were similar to those for clutch size and survival in the two least polluted sites, but not for the most polluted site, due possibly to biased mortality of smaller snails at this site. After correction for size biased mortality, the growth estimates showed patterns similar for the two polluted sites when compared to the reference site. This study suggests that long-term in situ exposure to genotoxic pollution may effect population fitness due to the accumulation of latent heritable genetic damage.
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Agars, Robert C., University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "Assessment of the potential environmental effects of soluble hydraulic oil on natural waters." THESIS_CSTE_SFH_Agars_R.xml, 2001. http://handle.uws.edu.au:8081/1959.7/249.
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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.Master of Science (Hons)
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de, Souza Machado Anderson Abel [Verfasser]. "Coastal pollution of aquatic systems : Literature review and experiments focusing on metal fate on estuaries / Anderson Abel de Souza Machado." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1149513004/34.
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Kannan, Narayanan. "A robust methodology to predict diffuse source pollution in the aquatic environment : A case study for the Colworth catchment, Bedfordshire." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/11355.
Full textAbstract:
Throughout the world, increased use of agrochemicals, warrant urgent measures to
minimise their
impacts on the aquatic environment. Monitoring is the usual practice
to
identify and quantify pollutants, however, it is an after-the-fact occurrence, and
monitoring over large spatial scales is not feasible. Mathematical models provide
an alternative to
monitoring and can be used both to forecast future pollution and to
investigate the impacts of potential control measures. This thesis is therefore
focussed on catchment scale
modelling of pesticide pollution of rivers.
Data from a 142-ha
agricultural catchment on the Unilever Colworth estate, have
been used to model
pesticide pollution at the catchment scale. After a review of
available models SWAT-2000 was selected as the modelling tool. An acceptable
performance in hydrological modelling, along with correct simulation of the
processes driving the water balance were essential first requirements. After
modification of the SWAT-2000 source code, hydrological simulation, crop growth
and
evapotranspiration patterns were realistic when compared with monitored data
SOUTCGS.
Hydrological modelling was carried out using both daily and sub-daily data with
Hargreaves and Penman-Montieth methods of evapotranspiration and the NRCS-
Curve Number and
Green-Ampt methods of runoff generation. A sensitivity
analysis identified GWQMN, AWC and ESCO as the most sensitive parameters.
These control baseflow, water content of soil layers, and depth distribution of
evaporation from the soil respectively. The best combination of runoff generation
and
evapotranspiration components was identified as Curve Number with
Hargreaves.
Modelling of sediment and pesticide loss was carried out for four pesticides.
Various
management scenarios were designed and tested with the objective of
reducing pesticide loss to streams and a web-based tool was developed to give
advice on
pesticide application. With the modifications implemented, it has been
demonstrated that SWAT is a useful tool for modelling pesticide behaviour at
catchment scale in UK conditions.
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Erasmus, Deborah Vivian. "Metal bioaccumulation, membrane integrity and chlorophyll content in the aquatic macrophyte ceratophyllum demersum from the Diep River, Western Cape." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2027.
Full textAbstract:
Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2012.The Diep River is approximately 80 km in length and runs through agricultural land and urban parts of greater Cape Town, South Africa before entering the Atlantic Ocean, via an estuary. Generally, metal pollution in South African rivers is not well documented and using plants to monitor metal bioaccumulation is even less documented. The aim of this study was to investigate aluminium, iron, copper and zinc metal pollution in the Diep River and bioaccumulation of these metals in the leaves and stems of the submerged macrophyte Ceratophyllum demersum L. Furthermore, the effects of bioaccumulated metals on membrane integrity and chlorophyll content of these plants were investigated. Site 1 was situated in the upper reaches of the river adjacent to agricultural land, while site 2 was in an urban area, where industrial activities predominate. C. demersum (from an uncontaminated source) were introduced into the river at the two sites and compared with one another on a fortnightly basis over a 12 week period. Plants at site 2 were also compared to existing plants that were naturally growing at the site. Comparisons were also made between leaves and stems of the plants, to establish the organ of preference regarding metal accumulation and storage. Samples were digested with nitric acid and an ICP-MS was used to analyse metal concentrations in the water, sediment and plants. Chlorophyll extraction was done using dimethyl sulphoxide (DMSO) and the absorbance values determined using a spectrophotometer. Chlorophyll a, chlorophyll b and total chlorophyll contents were recorded and compared. Cell membrane integrity was determined by leaving plants for 24 hours in deionised water and measuring electrical conductivity and solutes (sodium, calcium, potassium and magnesium) before and after placement of the plants.
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Yi, Xianliang Andy, and 易先亮. "A comprehensive study on the ecological toxicity and risk of triphenyltin to aquatic organisms." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/202351.
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Clements, William H. "Community responses of aquatic macroinvertebrates to heavy metals in laboratory and outdoor experimental streams." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53937.
Full textAbstract:
This research describes aquatic macroinvertebrate community responses to heavy metals (copper, zinc) in experimental streams and at metal-impacted sites in the field. Experiments employed substrate-filled trays which were colonized in the field and then transferred to laboratory or outdoor streams.
Laboratory experiments conducted over three seasons showed that acute (96 h) exposure to copper (Cu) at 15-32 μg Cu/L significantly reduced macroinvertebrate abundance and number of taxa during each season. Owing to differences in sensitivity among taxa, the percent composition of dominant groups varied between control and dosed streams. Mayflies were quite sensitive to Cu, particularly during the summer when water temperatures were higher.
Community responses to Cu and Zn in outdoor experimental streams were similar to those observed at metal-impacted sites in the field. Control streams and field reference Stations were dominated by mayflies and Tanytarsini chironomids. In contrast, treated Streams and impacted field sites were dominated by net-Spinning caddisflies (Hydropsychidae) and Orthocladiini chironomids. The similarity of these experimental results to those observed in the field suggest that macroinvertebrate community responses to heavy metals are highly predictable.
Responses of these communities to Cu were greatly influenced by water quality. Effects were more severe in New River Streams, where water hardness and alkalinity were low, compared to Clinch River Streams, where hardness and alkalinity were higher. In soft water Streams, abundance was reduced by 84% after 10 d exposure to Cu (measured concentration = 13 μg/L). In contrast, abundance was reduced by only 45% in hard water Streams after 10 d at Similar Cu levels. These results demonstrate the importance of accounting for water quality characteristics of receiving systems when establishing site-specific criteria for metals.
Chronic exposure (14 d) to sublethal levels of Cu (< 6 μg/L) increased Vulnerability of caddisflies (Hydropsyche morosa and Chimarra sp.) to predation by the Stonefly, Paragnetina fumosa. Caddisflies were also the major component of stonefly diets and were consumed Significantly more frequently in dosed Streams than controls. These results demonstrate that single Species bioassays were inadequate for predicting effects of toxicants on community level processes.Ph. D.