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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Stelco's Lake Erie Works

LoSchiavo, Michael 04 1900 (has links)
<p> The major emphasis of this paper concerns the location of Stelco 1 s Lake Erie Works at Nanticoke. The paper puts into perspective Stelco's decision to build a new integrated steel works. Stelco had to increase its capacity by an estimated six-million tons to ensure its competitiveness up to the year 2000. Hilton Works could at best only produce a five and a half to six million ton annual capacity and had no room available to expand its operation. </p> <p> Stelco therefore set out on an intense search to find a suitable location to develop a new integrated steel plant. Nanticoke Ontario, on the north shore of Lake Erie, was finally chosen as the site. Overall, the differences between Hamilton and Nanticoke are small and it was chiefly the space available and better labour relations at Nanticoke that influenced Stelco's choice of location. Construction of Lake Erie Works began in 1974 and the first phase was completed in 1980. </p> / Thesis / Candidate in Philosophy
22

The Paleoecology of Some Middle Devonian Fossil Clusters, Erie County, New York

Bray, R. 04 1900 (has links)
<p> Extensive bedding plane exposures in the Ludlowville shales along Cazenovia Creek near Spring Brook, New York display the spatial distribution of the skeletal remains from a marine faunal assemblage. Fossils typically occur in aggregates that are subcircular in plan view and plano-convex in cross-section with the convex side down. The clusters measure 1 meter in diameter and 2 centimeters thick at the center. This dispersion pattern has led to a general consideration of the different mechanisms responsible for creating fossil aggregations. Possible mechanisms, a spectrum from biological to geological, have been categorized into reproductive, ecological, postmortem redistributional, and preservational modes of formation. </p> <p> Quantitative sampling of the most abundant species, Ambocoelia umbonata, in four successive 5 millimeter layers within three clusters was carried out to determine which process is responsible for cluster formation. Between level variation in shell parameters demonstrates that fragmentation, distortion and valve ratios are independent of trends in position, density, and disarticulation. The trends are not controlled by geological agents, but rather result from ecological conditions. Furthermore, the size distributions of Arnbocoelia are bimodal and have to be explained on a biological basis. This has led to an interpretation of cluster development involving initiation by occasional spat survival on a somewhat "lethal" substrate, subsequent succession and regulation by ecological requirements, and final termination due to failure of spat recruitment probably because of fecal and/or decay toxin buildup. </p> / Thesis / Master of Science (MSc)
23

Science and community monitoring to inform management of phosphorus in the Canadian Lake Erie watersheds

Tedeschi, Alana C. January 2023 (has links)
Algal blooms in Lake Erie have worsened in severity, extent, and duration due to agricultural phosphorus (P) loading. Science, policy, and community action are needed to identify and implement feasible solutions for freshwater protections. To improve conservation action for P-reduction in the Lake Erie watershed, we must understand landscape drivers that enhance P runoff across agricultural regions with seasonal and spatial variation. The goals of this thesis were to assess landscape determinants of seasonal P variations in the understudied Canadian Lake Erie watershed, and to develop tools to amplify community stream monitoring and environmental engagement. A seven-year dataset revealed that P loading has significantly increased on an annual basis (2012 – 2019) in the late-winter-early-spring (February, March, April) in three separate Lake Erie tributaries (the East Sydenham River, the Thames River, and the Grand River). I demonstrated that year-over-year increases in tile drainage area on farms explained 23 – 49% of the year-over-year increases in P loading; however, I found the effects of tile drainage were moderated by differences in soil texture, land use/land cover, regional climate, and urban point sources. Using a nested-watershed approach for one year in 13 monitoring stations of the mixed-use Grand River watershed, I determined that row crop area was a strong predictor of P concentration in the Grand River when fields are bare, soils exposed, and nutrient assimilation by biota nonexistent. I recommend the use of year-round field cover by cover crops as a conservation measure to attenuate P-enrichment in the Grand River since sub-watersheds with increased cover crop proportion had reduced P concentrations and turbidity throughout the year. In another one-year study of 13 sub-watersheds across a gradient row crop and tile-drained sub-watersheds of the East Sydenham River and Grand River, I provided quantitative evidence of the negative effects of intensively row crop and tile-drained sub-watersheds on soluble reactive P export during late-winter-early-spring, and particulate loss during the growing season. To engage agricultural communities in monitoring P export from farms, I developed a bioassay that uses stream algae to determine P concentration in low-order streams. This method involving substrate rods (i.e., Peristix) is cost-effective, requires very little training, and yielded data that were significantly related to P concentrations in agricultural streams in the growing season. I recommend that environmental agencies and landowners use this bioassay to identify areas to implement conservation measures to reduce P export from the Lake Erie watershed. For greater application of community-science tools, I created the CommunityFIRST framework, which emphasizes feasible community collaborations, inclusive volunteerism involving a range of abilities and knowledge systems, using tools developed in this thesis that are relevant to the community’s environmental issues and carried out in a supportive and trusting environment between researchers and community members. My research integrates science and community methods to advance our understanding of agricultural land management and seasonal P loading from the Canadian Lake Erie watershed. / Thesis / Doctor of Philosophy (PhD) / After decades of improvement, Lake Erie eutrophication continues to be a water-quality issue in the Great Lakes Basin. Year after year, algae blooms cover the lake and call scientists, politicians, and communities to action. Phosphorus runoff from agricultural activities is at the core of this issue, and a better understanding of phosphorus runoff is needed across all Lake Erie watersheds and during all seasons of the year. The goals of this thesis were to assess landscape determinants of seasonal variations in phosphorus in the understudied Canadian Lake Erie watershed, and to develop tools to amplify community stream monitoring and environmental engagement. Spanning three major Canadian Lake Erie tributaries, I analyzed the effects of agricultural intensity, agricultural management practices, and changing seasonality on phosphorus export. I determined critical periods and specific landscape characteristics and compositions that can enhance phosphorus runoff from agricultural fields, and I offered recommendations to guide management decisions in the Canadian Lake Erie watershed. At the local scale, I developed a feasible stream monitoring tool for community-science initiatives. My research integrates science and community methods to advance the overall understanding of agricultural land management and seasonal phosphorus export from the Canadian Lake Erie watershed.
24

A Survey of the Helminth Parasites of Fishes From the Lake Erie and Ohio River Drainage Areas

Pearce, William J. January 1950 (has links)
No description available.
25

Phylogeography of Smallmouth Bass (Micropterus Dolomieu) and Comparative Myology of the Black Bass (Micropterus, Centrarchidae)

Borden, William Calvin 05 May 2008 (has links)
No description available.
26

AN ECOLOGICAL ASSESSMENT OF OHIO FISH COMMUNITIES AND HABITAT STRUCTURE: EXAMINING THE RELATIONSHIP BETWEEN COMMUNITY COMPOSITION AND HABITAT QUALITY FOR AQUATIC ECOSYSTEMS

Laurich, Ryan Michael January 2003 (has links)
No description available.
27

Temperature Influences of Lake Erie

Schloemer, Robert W. January 1937 (has links)
No description available.
28

Origin of Crystal Rock Cave, Ohio, USA and its record of Lake Erie variation through speleothem analyses

McDaniel, Kyle 14 September 2018 (has links)
No description available.
29

Assessing the Potential for Differential Contributions of Spawning Stocks to Lake Erie Yellow Perch Populations

Collingsworth, Paris Dever 05 November 2009 (has links)
No description available.
30

Physiological Ecology of <i>Microcystis</i> Blooms in Turbid Waters of Western Lake Erie

Chaffin, Justin D. 23 September 2009 (has links)
No description available.

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