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 12 of 12 for “"Unionids"”.
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The influence of hydrological variability on the spatial distribution and orientation of freshwater mussels (Bivalvia: Unionidae).
… characterized stable sites. Apparently, some unionids can be associated with specific hydrological river types and their distribution can be predicted using flow-related stream attributes. The patterns of burrowing and orientation were examined in unionids with respect to hydrological …
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Energy Reserves in Native Freshwater Mussels (Bivalvia:Unionidae) with and without Attached Zebra Mussels: Effects of Food Deprivation
… in quarantine affects body condition of unionids, and 3) what feeding regime maintain unionid condition in quarantine. The effects of zebra mussel infestation on two mussel species were evaluated through glycogen analyses of mantle tissue and gut content analysis. Specimens of Amblema p. …
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Characteristics of the Unionid Community and Habitat in a Power Plant Thermal Plume in Western Lake Erie
Native unionids are endangered in the Laurentian Great Lakes due to habitat degradation and biofouling by dreissenids. However, a robust community was discovered living within the thermal discharge of a power plant at Oregon, Ohio, on the south shore of Lake Erie. Chapter 1 describes comparisons of …
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Historical and contemporary distributions of aquatic mollusks in the upper Conasauga River system of Georgia and Tennessee
… River historically supported 37 species of unionids (Bivalvia: Unionidae), 11 species of prosobranch gastropods (Mollusca: Gastropoda), and 3 species of sphaerid (Bivalvia: Sphaeridae) clams. I collected records from several museums ranging from 1914 to 1990 to chronicle the historical …
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Abiotic and biotic factors influencing the decline of native unionid mussels in the Clinch River, Virginia
… and impairs growth of juvenile unionids in-situ studies. The intermittent toxicity which may be associated with rain events impairs stream biota and may prevent recruitment of juvenile unionids. The presence of adult C. fluminea in sediments was found to decrease juvenile unionid …
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Approaches for assessing toxicity of selected contaminants to freshwater mussels (Bivalvia: Unionidae)
… toxicants. However, toxicological databases for unionids are rather limited because standard test methods are yet developed, and no published studies report endpoints for chronic test that are > 9 days. The primary goals of my thesis research were to assess acute and chronic toxicities of …
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Fort Union (Paleocene) mollusks from southern Golden Valley and southeastern Billings counties, North Dakota
… all nine of the species which include: two unionids, Plesielliptio priscus (Meek and Hayden) and Rhabdotophorus senec tus (White); one corbulid, Bicorbula mactriformis (Meek and Hayden); and six viviparids, Viviparus retusus (Meek and Hayden), Viviparus trochiformis (Meek and Hayden), …
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Assessing Freshwater Mussels (Bivalvia: Unionidae) in South Dakota and Identifying Drivers of Assemblage Variation
… Of the 202 survey sites, 91 showed evidence of unionids and 44 sites had live mussels. At sites where live mussels were encountered (n=44), quantitative adaptive cluster sampling was conducted during 2016 to estimate population densities and environmental drivers of assemblage variation. Average …
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Evolution of gender associated mitochondrial DNA in bivalves
… more rapidly than the F type mtDNA in the unionids; however, this increase in rate of evolution appears to be largely due to male driven evolution and not relaxed selection. Lastly, the increase in rate of the F type Mytilus mtDNA relative to other metazoans is not seen in the unionid …
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Holocene Mollusks of the Knife and Heart Rivers, Southwestern North Dakota
… 4 species from the Heart River.</p> <p>Of the unionids, Leptodea laevissima (Lea) occurs alive in the lower reaches of both rivers but does not occur as a fossil. One specimen of Lampsilis ventricosa (Barnes) establishes the existence of this species in the Missouri River drainage presently; …
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The Effect of Dieoffs of Asian Clams (Corbicula fluminea) on Native Freshwater Mussels (Unionidae)
… fluminea, may be having an effect on native unionids. Negative impacts may result directly from competition or indirectly, because of Corbicula population crashes that release ammonia and reduce dissolved oxygen in the sediment. Laboratory tests were conducted to determine the relative …
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Use of an environmentally realistic laboratory test organism and field bioassessments to determine the potential impacts of active coal mining in the Dumps Creek subwatershed on the Clinch River, Virginia
This research was divided into four objectives for assessing the impacts of coal mining on ecosystem health. The first objective was to provide an ecotoxicological assessment in the upper Clinch River using standard bioassessment techniques. Analysis of sediments and interstitial water (porewater) …