Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 24 for “"biomagnification"”.
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FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A.
A number of studies suggest that Hg biomagnification in aquatic systems are dependent on two factors: a source of mercury and the potential for this mercury to become methylated. To compare the importance of these two factors in a riverine system I examine sites with varying sediment total mercury …
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FACTORS AFFECTING MERCURY BIOMAGNIFICATION IN RIVERINE FOOD WEBS IN THE ROCKY MOUNTAINS: CLARK FORK RIVER BASIN, MONTANA, U.S.A.
A number of studies suggest that Hg biomagnification in aquatic systems are dependent on two factors: a source of mercury and the potential for this mercury to become methylated. To compare the importance of these two factors in a riverine system I examine sites with varying sediment total mercury …
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Unifying ecosystem concepts and mercury biomagnification in an estuarine environment using stable isotopes (delta-carbon-13 and delta nitrogen-15).
… food web structure and patterns of mercury biomagnification. On a delta13C and delta15N basis, three different sources of energy were identified: terrestrial carbon, in situ estuarine primary production, and marine phytoplankton. Isotopically depleted delta13C and delta15N values verified …
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Mercury Concentrations in Fish from the Guadalupe River, Texas: Relationships with Body Length and Trophic Position
… at 4 of the 5 sites, indicating that Hg biomagnification is occurring at these sites. The biomagnification factor differed between sites, however it was not positively correlated with food chain length. Among species, the estimated trophic level was the strongest predictor of Hg …
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An assessment of the biodistribution, persistence, and health impacts of microplastics and nanoplastics in fish
… the trophic transfer, bioaccumulation, and biomagnification of microplastics and nanoplastics. I found that in most of the literature there was clear evidence of trophic transfer, equivocal evidence for bioaccumulation, and no evidence for biomagnification. I drew upon these noted knowledge …
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Mammalian carnivores as bioindicators to evaluate the exposure and bioaccumulation of organic contaminants in terrestrial ecosystems
… species- or analogue-dependent bioaccumulation, biomagnification, or metabolism of Dechlorane chemicals in different food webs. My findings, along with previously reported food web models, suggest Dechloranes may possess substantial bioaccumulation and biomagnification potencies in terrestrial …
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Model of PAH and PCB bioaccumulation in Mya arenaria and application for site assessment in conjunction with sediment quality screening criteria
… criteria approaches lack is the bioaccumulation/biomagnification of contaminants. Nor are there accurate, easily implemented models for benthically-coupled organisms such as Mya arenaria. In this document a bioaccumulation model for PAHs and PCBs was developed. The model considers contaminant …
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Solid phase microextraction of amino-dinitrotoluenes in tissue.
… indicators of toxicological bioavailability and biomagnification potential of tissue-associated organic compounds.
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Stable Isotopes As Intrinsic Markers of Contaminant Dynamics in the Lake Winnipeg Food Web
… sources were often evident at fine scales. Biomagnification (south basin) and bioaccumulation (north basin) of Hg were observed within the lake’s walleye populations. Fortunately, analysis of walleye scales demonstrated some utility in monitoring fillet-Hg concentrations. Mercury, as well as …
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Contamination of a soft-water stream ecosystem in southwest Virginia by highway-generated heavy metals
… column contained the lowest concentrations. Biomagnification of these four metals was not demonstrated. Significant bioaccumulation of lead, nickel, and cadmium in bone; and cadmium in the kidneys of fish was found to occur. Major biological uptake of lead, nickel, cadmium, and zinc in these …
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The use of Chironomus riparius (Diptera: Chironomidae) in benthic toxicity tests and its response to selenium
… selenium criteria may not protect against biomagnification in all ecosystems, and should be based on some environmental chemical factors.
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An investigation of the factors affecting mercury accumulation in lake trout, Salvelinus namaycush, in northern Canada
… concentrations. In addition, trophic and mercury biomagnification relationships, as inferred from stable carbon and nitrogen isotope analyses, for the two lake trout populations were compared. Lake trout from the NT exhibited significantly higher mercury concentrations than those from the NAS …
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Attraction and risk in urban bird habitats
… and birds, but no consistent pattern of biomagnification is present across trophic levels and concentrations for most taxa are relatively low. The results of this investigation have broad implications for the management and restoration of urban bird habitats and will contribute to the …
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The effects of a toxic metals spill on aquatic fauna in streams near Culpeper, Virginia
… from the spill site did occur, however biomagnification did not.
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Non-lethal methods for assessing the health and status of fish species of conservation concern.
… the primary modulator in apex predators, rather biomagnification through diet is likely the main driver of Hg concentrations. Results from the second case study demonstrate that enrichment from wastewater can impact stable isotope signals causing a decoupling between predator and prey …
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Bioaccumulation of persistent organic pollutants and trace metals in Scottish marine food webs and their relationship with trophic level and fatty acid signatures.
… available. Secondary poisoning is a result of biomagnification, which can be expressed as the trophic magnification factor (TMF; the average increase in concentration per trophic level). Fatty acid (FA) signatures and stable isotope (SI) ratios were used to develop an understanding of Scottish …
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Polonium-210 in Freshwater Environments: Analytical Advances, Predictive Modelling, Food Web Transfer and Dose Assessment
… Trophic magnification factors demonstrated clear biomagnification of ²¹⁰Po and trophic diminution of ²¹⁰Pb, with ²¹⁰Po:²¹⁰Pb activity ratios increasing with trophic position, reflecting preferential assimilation of ²¹⁰Po. Site- and tissue-specific transfer parameters (bioaccumulation factors, …
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Mercury Concentrations in Snowy Plovers and Sediments of their Breeding Environments in the Southern Great Plains
… linkages between sediment THg levels and biomagnification potential, or trophic transfer, throughout local food chains.</p> <p>Very few THg adverse effect threshold data are available to quantify toxicity risk for shorebirds, but snowy plover blood THg concentrations were consistent with …
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Caracals as sentinels for metal exposure in a human-transformed landscape
… be at increased risk of metal exposure through biomagnification effects. Relatively little is known about this emerging threat to terrestrial carnivores persisting in human-transformed landscapes, especially in the Global South. To better understand the extent of this issue, I quantified the …
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Impacts of artisanal and large scale gold mining on tropical rivers in West Africa: A case study from the Brong Ahafo Region of Ghana
… community structures and resulted in mercury biomagnification in fish. ASGM impact on river water and sediment quality was determined using a reversed BACI (Before/After and Control/Impact pairing) experimental design, whilst that of LSM used a conventional BACI design. Impacts on …
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