Physical Sciences and Mathematics Commons^™

Advances In Amino Acid Analysis For Marine Related Matrices And Its Application To Coastal Shelf Settings In The Canadian Arctic, Rachel M. Mcmahon

OES Theses and Dissertations

Amino acids comprise up to 50% of organic matter in cellular material and are a major fraction of oceanic organic carbon. Amino acids are also considered highly labile during organic matter recycling, making them useful proxies for organic carbon cycling. Nevertheless, analysis of individual amino acids has been burdened by lengthy derivatization and complex analysis since the 1950s. In this thesis, I describe the modification of advanced analytical techniques, developed in the biomedical field, for analysis of marine matrices which allow the determination of at least 40 amino acids without the need for lengthy sample preparation and derivatization, twice the …

Plastics And Microplastics As Vectors For Bacteria And Human Pathogens, Amanda Lee Laverty

OES Theses and Dissertations

Since plastics degrade very slowly, they remain in the environment on much longer timescales than most natural substrates and can thus provide a novel habitat for colonization by bacterial communities. The full spectrum of relationships between plastics and bacteria, however, is little understood. The objective of this study was to examine marine plastic pollution as a substrate for bacteria, with particular focus on Vibrio spp., including the human pathogens, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus.

Colonization experiments were set up in a tributary of the lower Chesapeake Bay to follow Vibrio spp. colonization and …

Biogeochemical Cycling Of Selenium In The Arctic Ocean, Kyle M. Mcquiggan

OES Theses and Dissertations

Changes in the global climate may have a pronounced effect on the biogeochemical cycling of trace elements like selenium (Se) in the Arctic Ocean. This study described the first quantitative examination of the biogeochemical cycle of selenium in the Amerasian Basin, providing the baseline from which future changes can be identified. Aerosol, dissolved and particulate water samples were collected for Se determinations during the U.S. GEOTRACES GN01 Arctic expedition that sampled the two parts of the Amerasian Basin in 2015: The Makarov Basin on the way to the North Pole and the Canada Basin on the return trip to Dutch …

Regional Sea Level Rise Along The United States Coasts, Alessandra G. Burgos

OES Theses and Dissertations

Over the past several years, there has been several studies focused on reconstructing global mean sea level (GMSL) for the 20th century, along with projecting rates out into the future. Of greater importance for mitigation and adaptation plans, however, is the rate of local or regional sea level (RSL) rise. Ocean dynamics along with changes in Earth’s gravitational field can cause RSL to deviate from the change in GMSL. During the satellite altimeter era covering the past two decades, RSL trends can be four times the global average, with much of this spatial variation due to internal climate variability. Isolating …

Wet And Dry Atmospheric Deposition Of Nutrients And Bioactive Trace Metals To Coastal Waters Of The Mid-Atlantic Bight, Christine Sookhdeo

OES Theses and Dissertations

Atmospheric deposition provides a significant source of nutrients and bioactive trace metals to the surface ocean, including the seasonally oligotrophic waters of the Mid-Atlantic Bight. These atmospherically derived nutrients and trace metals enter the surface ocean via dry deposition of aerosols and wet deposition in rain. To estimate the aeolian input of nutrients and trace metals to coastal waters east of the Delmarva Peninsula, wet and dry atmospheric deposition samples were collected over a one-year time series at the Anheuser-Busch Coastal Research Center, Oyster, Virginia. Weekly composite samples were collected from May 2014 through June 2015. Nutrient species examined were …