Thesis (Ph.D.)--University of Delaware, 2008. / Principal faculty advisor: Steven K. Dentel, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

Honors Project--Smith College, Northampton, Mass., 2009. / Includes bibliographical references (p. 78-80).

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.S.)--University of Nevada, Reno, 2008. / "December, 2008." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (M.S.)--Rochester Institute of Technology, 2008. / Typescript. Includes bibliographical references (p. 50-51).

Thesis (Ph. D.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2005. / Includes bibliographical references.

Thesis ( Ph.D. ) -- McMaster University, 2004. / Includes bibliographical references (leaves 181-194). Also available via World Wide Web

Atmospheric deposition (AD) is a significant but poorly understood source of nutrients to many aquatic systems around the world. Accurate characterization of the nutrient budgets of aquatic systems is critical to good management decisions, so a better understanding of AD-related nutrient loads is essential, especially for water bodies where nutrient loads from atmospheric deposition are significant. Due to its large surface area, proximity to Great Basin dust sources, high values of atmospheric particulates due to inversions, and the high phosphorus content of local soils, Utah Lake, in the semi-arid Utah Valley, USA, experiences significant phosphorus loading from AD. The lake is eutrophic and has a history of impaired water quality and HABs, which has motivated significant study and debate over nutrient loads to the lake. Previous studies that measured phosphorus AD to Utah Lake showed a large portion of the AD was associated with a few high-volume deposition events, with the data exhibiting unexpectedly high peaks at some locations on a few dates. These issues cast doubt on the data. We used statistical analyses and machine learning models to characterize AD to Utah Lake. In addition to determining the distribution of AD events, we analyzed the relationship between phosphorus AD and local weather events. We used this analysis to determine whether the high phosphorus measurements were outliers due to sampling errors or represented actual conditions. Our analysis shows that AD events followed an XXX distribution, similar to the distribution of precipitation events on the lake. We found the high phosphorus deposition events were correlated with instances of high wind occurring when the ground was dry. We also observed regular cycles of higher and lower measurements throughout the year that are like measures of atmospheric particulate matter. We conclude that atmospheric phosphorus deposition on Utah Lake is episodic and driven by weather conditions around the lake, with the most important factors being the number of hours with high winds during a collection period and the percentage of those hours where the ground was dry during a collection period followed by dry deposition from particulate matter. This is an important finding for the management of Utah Lake and also has implications for the management of other eutrophic lakes in which atmospheric deposition of nutrients impacts water quality.

Atmospheric deposition (AD) is a significant source of nutrient loading to waterbodies around the world. However, the sources and loading rates are poorly understood for major waterbodies and even less understood for local waterbodies. Utah Lake is a eutrophic lake located in central Utah, USA, and has high nutrient levels. Recent research has identified AD as significant sources for nutrient loading to the lake to better understand the dust AD sources, we sampled suspected source locations and collected deposition samples around the lake. We analyzed these samples using Inductively Coupled Plasma (ICP) for 25 metals to characterize their elemental fingerprints. We then compared the lake samples to the source samples to determine likely source locations. We computed spectral angle, coefficient of determination, multi-dimensional scaling, and radar-plots to characterize the similarity of the samples. We found that lake deposition samples were more similar to local sources than to distant sources. This suggests that the major source of atmospheric deposition onto Utah Lake is the local empty fields south and west of the lake and not the farther playa sources as previously suggested. Preliminary data suggest that dust AD is associated with dry, windy conditions and is episodic in nature. We show that AD from dust deposition is likely a small portion of the overall AD nutrient loading on Utah Lake, with the dry and precipitation source contributing the majority of the load.

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