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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.
501

Selenium and trace metal accumulation in detrital-benthic food webs of lotic and lentic wetlands, Utah, USA

Hillwalker, Wendy E. 24 May 2004 (has links)
Concentrations of selenium (Se), manganese (Mn), zinc (Zn), cadmium (Cd), lead (Pb) and arsenic (As) were measured in the water column, sediment and biota, in conjunction with selected physicochemical data, from representative wetland types at a mining site within Salt Lake County, Utah, USA. The selected field sites included Oolitic Pond (lentic) and Lee Creek (lotic), which are moderately contaminated brackish, alkaline aquatic wetlands managed by a copper mining industry. These fishless wetlands are located in a geographic region that poses risk to migratory shorebird populations from dietary Se. A spatial sampling study demonstrated the extent of variation in total Se concentration within the wetlands. With the exception of the sediment compartment, Se concentration did not differ significantly along the 2-mile length of Lee Creek or within the Pond. The differences in sediment total Se concentrations between the Creek East and West segments characterize lower Lee Creek as having two segments distinguished by unique processes that influence the sediment Se accumulation profiles. Se accumulation trends were observed temporally over 3-years (2000 to 2002) and over two seasons (spring and autumn). Total Se body burden in benthic invertebrates was more clearly associated with sediment/detritus Se concentrations than with surface water concentrations. Three invertebrate groups dominated the aquatic invertebrates assemblage in the lotic and lentic benthos; primary consumers (Chironomidae, Diptera), generalist feeders (Hemiptera) and predators (Odonata). The chironomid larvae accumulated 1.3 to 39 times the trace metal concentrations of the Hemiptera or odonate taxa, independent of trace metal type (essential or non-essential) or wetland occupation. Organism-specific factors, such as habitat selection and preferential feeding habits, were proposed to influence benthic invertebrate accumulation profiles by modifying trace metal exposure. Mixed diets, trophic omnivory and the complexity of wetland biogeochemistry limit the power of stable nitrogen fractionation signatures to define benthic food web relationships. Wetland site-specific processes impacted Se accumulating efficiency, with trace metal concentrations from 4 to 7 times greater within the lentic benthic system than the lotic. The fractionation of the natural abundant stable carbon isotopes revealed the importance of sedimentary and detrital organic carbon as dietary sources for the benthic food web. Sediment organic content was not significantly associated with sediment, or invertebrate, Se accumulation profiles. Ecological risk assessments based on sound understanding of metal chemistry and the interactions between the sediment matrix and benthic organisms are necessary to provide tools for environmental management. / Graduation date: 2005
502

Faulting and basin geometry beneath the Great Salt Lake: implications for basin evolution and cenozoic extension

Mohapatra, Gopal Krishna, 1968- January 1996 (has links)
No description available.
503

Early Mormon woodworking at its best : a study of the craftsmanship in the first temples of Utah /

Welch, Thomas Weston. January 1983 (has links)
Thesis (M.S.)--Brigham Young University. Dept. of Industrial Education. / Bibliography: leaves 95-96.
504

The history and effect of apostasy on a small Mormon community.

Holley, Henry Orvil. January 1966 (has links)
Thesis (M.A.)--B.Y.U. Dept. of Graduate Studies in Religious Instruction.
505

The influence of the southern Nevada and southern Utah folklore upon the writings of Dr. Juanita Brooks and Dr. LeRoy R. Hafen.

Hardy, Pansy L., January 1965 (has links)
Thesis (M.A.) B.Y.U. Dept. of English. / Bibliography.
506

Elevation, longitudinal profile, and schmidt hammer analysis Of strath terraces through Capitol Reef National Park, Utah : bedrock channel response to climate forcing? /

Eddleman, James L., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2005. / Includes bibliographical references.
507

Mapping and kinematic structural analysis of the Deep Creek fault zone, South Flank of the Uinta Mountains, Near Vernal, Utah /

Haddox, David A., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2005. / Includes bibliographical references (leaves 75-88).
508

Parowan pottery and Fremont complexity : late formative ceramic production and exchange /

Watkins, Christopher N., January 2006 (has links) (PDF)
Thesis (M.A.)--Brigham Young University. Dept. of Anthropology, 2006. / Includes bibliographical references (p. 118-136).
509

Parowan pottery and Fremont complexity late formative ceramic production and exchange /

Watkins, Christopher N., January 2006 (has links) (PDF)
Thesis (M.A.)--Brigham Young University. Dept. of Anthropology, 2006. / Includes bibliographical references (p. 118-136).
510

Salt Lake City's urban growth and Kennecott Utah Copper a geographical analysis of urban expansion onto a previously proposed Superfund site adjacent to the world's largest copper mine /

Lemmons, Kelly Kristopher, January 2008 (has links)
Thesis (M.S.)--University of Massachusetts Amherst, 2008. / Includes bibliographical references (p. 93-97).

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