Fresh Water Studies Commons^™

Groundwater And Tidal Controls On Wetland Hydrology, Julie J. Metz Wetland Mitigation Bank, Woodbridge, Virginia, Benjamin Stuart Hiza

OES Theses and Dissertations

Julie J. Metz Wetlands Mitigation Bank, a 92-hectare freshwater wetland located in Woodbridge, Virginia, borders the tidally-influenced Neabsco Creek. Seven pods separated by earthen berms were built by Wetland Studies and Solutions Inc. (WSSI) in 1995 and 1997 by removing the toe of small sandy alluvial fans and covering the underlying coarse gravel bed with a low permeability cap. The basal Quaternary gravels were deposited in a creek valley incised into a thick sand-and-clay Cretaceous delta. The alluvial-fan apron developed at the base of steep slopes along the sides of the valley. Pressure transducer data from five monitoring wells along …

A Survey Of Aquatic Organisms For The Cyanotoxin Beta-Methylamino-L-Alanine (Bmaa), Ian M. Sammler

OES Theses and Dissertations

Cyanobacteria blooms are increasing globally as a result of eutrophication. Many cyanobacteria are potentially harmful, not only because of the oxygen depleted zones created when they decay, but also because of the toxins they produce. β- Methylamino-L-alanine (BMAA), reportedly produced by many species of cyanobacteria, is a non-proteinogenic amino acid that has been linked to the development of neurodegenerative diseases (amyotrophic lateral sclerosis (ALS) and Alzheimer's) in humans. This study presents results from an assessment of BMAA in cyanobacteria and their grazers from the lower Chesapeake Bay and Lake Erie regions. BMAA was analyzed in samples prepared with the EZ:Faast™ …

Fortnightly Variability At The Transition Between Two Sub-Estuaries, Mayra Lorena Riveron Enzastiga

OES Theses and Dissertations

Profiles of current velocity from an Acoustic Doppler Current Profiler (ADCP) and of water salinity, temperature and density from a Conductivity-Temperature-Depth (CTD) recorder, were combined with surface salinity, temperature and density from a Conductivity-Temperature (CT) recorder to elucidate the fortnightly variability at the Lafayette River entrance. The Lafayette River connects at its mouth with the Elizabeth River, which is a tributary to the James River in the Chesapeake Bay. Data were collected in four experiments during consecutive spring and neap tides in the autumn of 2000, and in the spring of 2001. Each experiment was carried out for -25 hours …

Non-Volatile Dissolved Organic Iodine In Marine Water, Xianhao Cheng

OES Theses and Dissertations

An analytical scheme for the determination of marine DOI has been established. The concentration of DOI is estimated as total iodine (TI) minus total inorganic iodine (TII). The concentration of total iodine is determined as [special characters omitted] after DOI has been oxidized to inorganic iodine quantitatively by intensive UV-irradiation and all the inorganic iodine in the samples had been converted to [special characters omitted] by the addition of NaClO.

Production of DOI in seawater can be via both non-phytoplankton and phytoplankton related processes. In the former, iodide is converted to DOI. In the latter, most likely, iodate is converted …

The Effect Of Polynuclear Aromatic Hydrocarbons On The Fecundity Of Acartia Tonsa (Calanoid Copepoda), Juanita Y. Grabarczyk

OES Theses and Dissertations

The concentrations of polynuclear aromatic hydrocarbons (PNAHs) were determined for several stations in the Elizabeth River. Thirteen PNAHs of the sixteen EPA priority pollutant PNAHs were present in the particulate fraction. The concentrations ranged from 10.0 ng/1 to 1000 ng/1. Ten of the sixteen EPA priority pollutant PNAH were present in the dissolved phase. Concentrations ranged from 2.0 ng/1 to 100 ng/1.

The environmental PNAHs concentrations were used to determine test concentrations. Bioassays were conducted to determine the effects of indigenous concentrations of seven predominant PNAHs (0.01 mg/1 to 2.4 mg/1 concentrations) on the fecundity of Acartia tonsa (calanoid Copepoda). …

The Growth And Feeding Behavior Of Juvenile Spot, Leiostomus Xanthurus Lacepede, In The Nursery Region Of The James River, Virginia, John Thomas Mccambridge Jr.

OES Theses and Dissertations

The in situ growth and feeding behavior of juvenile spot, Leiostomus xanthurus Lacepede, was investigated for populations in the nursery area of the James River, Virginia. Growth of juvenile spot was found to be fairly rapid (11.34 mm/month, standard length) during their first summer in the nursery grounds, but it levelled off in the autumn. The mean size of spot after the first year was calculated to be 195 mm total length. The weight-length relationship was log W = -5.018 + 3.246(log L), where W = wet weight in grams and L = standard length in millimeters.

Juvenile spot appeared …

Effect Of The Chesapeake-Elizabeth Sewage Outfall Virginia Beach, Virginia On The Distribution And Ecology Of Benthic Foraminifera, James M. Bates Jr.

OES Theses and Dissertations

Sediment and bottom water samples from seven stations at the Chesapeake Elizabeth sewage outfall, Virginia Beach, Virginia were collected in order to evaluate the effect of the outfall on benthic foraminifera. The top centimeter of sediment was analyzed for living and total (live plus dead) foraminiferal densities, chlorophyll a, sediment grain size, ATP, percentage of silt and clay, and total organic carbon. Bottom water salinity, temperature, and ammonia were also analyzed.

Living foraminiferal density increased from March to July and with distance from the outfall. Total foraminiferal density also increased from March to July. The set of environmental variables was …

Control Of Clay Mineral Distribution By Estuarine Circulation, James River Estuary, Virginia, Jean-Pierre Feuillet

OES Theses and Dissertations

A study was performed on the clay minerals of the James River estuary, Virginia, to determine the predominant factors that influence clay mineral distribution in the estuary. The factors of differential settling, flocculation, and diagenesis show minor or no effects on distribution, while estuarine circulation exerts the strongest influence upon the clay mineral distribution.

There are two clay suites in the James River estuary. The upper James River clay suite is a kaolinite, dioctahedral vermiculite, and mixed-layer suite, with kaolinite being the major mineral. The lower Chesapeake Bay clay suite is an illite, chlorite, and montmorillonite suite, with illite being …

Determination Of Nutrient Levels And Proposed Predictive Models For Phosphate In The Lafayette River, Norfolk, Virginia, John R. Montgomery

OES Theses and Dissertations

The Lafayette River, an Urban, well-mixed estuarine embayment, was sampled from October, 1970 to January, 1972 for phosphate, nitrate, nitrite, oxygen, water temperature and salinity. The mean values found for these samples were: oxygen saturation from 69% to 106% nitrate from 0 to 4 microgram-atoms per liter, and salinity from 13 ‰ to 24 ‰. The mouth of the Elizabeth River to Hampton Roads as also sampled from May, 1971 to August, 1971. The Lafayette and Elizabeth Rivers were also sampled over a 24 hour period in the summer of 1971 and the Lafayette River again in the winter of …