Oceanography Commons^™

The Photosynthetic Action Spectra Of The Phytoplankton And Their Role In Governing Spatial And Temporal Distribution: A Numerical Modeling Approach, William Morrow Willis

OES Theses and Dissertations

In the present study a numerical modeling approach is employed to examine the role of division spedific differences in photosynthetic action spectra in governing the relative size of diatom and dinoflagellate carbon synthesis along various marine light regime gradients. A radiative transfer model taking into account both Rayleigh and Mie atmospheric optical properties is employed to define the light regime incident on the sea surface. The hydrospheric light regime is defined by an exponential decay model with a correction for diffuse back scatter. Taken together, the atmospheric and hydrospheric models define the spectral composition and intensity of light in the …

Experiments In Attempted Interspecific And Interpopulational Hybridzation Of Grass Shrimp Of The Genus Palaemonetes (Caridea Palaemonidae), Mark Andrew Boston

OES Theses and Dissertations

The present study investigates the interfertility of Palaemonetes populations, Interspecific crosses were attempted between representatives of sympatric :populations of P. pugio, P. vulgaris, and P. intermedius, Intraspecific crosses were undertaken between geographically separated :populations of P. pugio. Laboratory conditions of 25°c, 25°/oo, and 14.5 hour photoperiod per day were maintained for all breeding attempts, Under these conditions interspecific hybridization of Palaemonetes pugio and P. vulgaris was not feasible. P. intermedius could not be hybridized with P. pugio and P. vulgaris. At 40 days of age P. pugio juveniles were significantly larger than P. vulgaris juveniles of …

The Relationship Of Bottom Sediments To The Current-Generated Topography On Crumps Bank And Willoughby Bank, Southern Chesapeake Bay, Virginia, Eugene Robert Brush

OES Theses and Dissertations

Crumps Bank and Willoughby Bank in Southern Chesapeake Bay are an area of varying topography. The area is bounded by two large bridge-tunnel spans, the dredged Thimble Shoal Channel borders it to the north, and the Ocean View section of Norfolk, Virginia lies to the south. The purpose of this investigation is to determine the relationship of the bottom sediments of Crumps Bank and Willoughby Bank.to the current-generated topography, and that this topography is the result of tidal currents.

The bathymetry, bottom sediment characteristics, bottom tidal currents, and the correlation of depth to various sediment parameters were examined to determine …

Description Of The Larval Development Of Squilla Empusa Say (Crustacea Stomatopoda) With Aspects Of Larval Ecology In Chesapeake Bay, Steven Gaines Morgan

OES Theses and Dissertations

Larvae of Sguilla empusa were collected from the plankton and were reared in the laboratory to describe the pelagic larval development and the postlarval stage. Nine pelagic stages are passed through before the postlarval stage is attained.

The larvae reared for descriptive purposes were subjected to sixteen combinations of temperature and salinity to determine their tolerance to the two parameters. Larvae survived longer and molted more frequently when reared at 25°/oo and 20°C or 25°C, which corresponds to the natural conditions of the Chesapeake Bay when the larvae were collected.

A three year planktonic survey conducted in the lower region …

Suspended Matter And Light Attenuation In A Turbid Estuary, Daniel E. Campbell

OES Theses and Dissertations

A study was made in Hampton Roads, Virginia, to characterize the suspended matter and to investigate its relationship to the light attenuation coefficient. The study gives a detailed description of the seston and its variations with time and space. An evaluation of the light attenuation coefficient as an indicator of seston distributional parameters was made.

The distribution of the suspended matter is obtained through gravimetric, Coulter counter and microscopic analyses. Microscopic analysis is employed to determine the composition of the seston and ATP determinations give the amount of living biomass. The suspended matter is characterized in terms of weight, numbers, …

Effect Of Nitrite And Nitrate On The Larval Development Of The Grass Shrimp Palaemonetes Pugio Holthuis, Carl Bingham Hinesman

OES Theses and Dissertations

The effects of nitrite and nitrate on survival and larval development of the grass shrimp Palaemonetes pugio were investigated in the laboratory. Nitrite concentrations assayed were 0 (control), 0.5, 1.0, 10, 25 and 50 mg NO₂/1. Nitrate concentrations tested were 0 (control), 100, 250, 500, 1000 and 2000 mg NO₃/1. Temperature and salinity conditions were 25 C and 25 ‰, respectively, and all tests occurred in the dark. Thirty-six larvae were reared in each assay, twelve from each of three adult females.

Nitrite levels of'5 and 50 mg NO₂/1 significantly reduced survival of larvae …

A Baseline Study On The Possible Mechanisms Of Larval Stomatopod Distribution On The Carolina Shelf, Carl Robert Berman Jr.

OES Theses and Dissertations

The South Carolina Marine Resources Institute provided the author with 198 station samples containing 2,193 stomatopod larvae. These larvae had been collected during ichthyoplankton Bongo tows on five separate cruises aboard the Institute's vessel R/V DOLPHIN (February, 1972 to January, 1975). The larvae were examined microscopically and divided into early, middle, and late stages according to known growth criteria. The larval distribution was plotted geographically, by seasons, and larval density (larvae/m3) was graphed against distance offshore. Using these data, together with the circulation characteristics on the Carolina Shelf, significant distributional data appeared which supported the hypothesis that the stomatopod population …

Temperature And Salinity Tolerance Of The Larvae Of The Sand Shrimp, Crangon Septemspinosa (Say), Karen Lyttle Hinsman

OES Theses and Dissertations

The effects of temperature and salinity on the larval development of the sand shrimp, Crangon septemspinosa, were investigated in the laboratory using 30 combinations of temperature and salinity in a five by six factorial experiment. The five temperatures were 5°c, 10°c, 15°c, 20°c, and 25°c and the six salinities were 10°/oo, 15°/oo, 20°/oo, 25°/oo, 30°/oo and 35°/oo. Thirty-six larvae were used for each temperature-salinity combination. Temperature and salinity produced significant differences (1% level) in survival and the duration of larval development. Highest survival occurred at 15°c and 20°/oo. At optimum temperatures (15°c to 20°c) larvae exhibited the broadest tolerance …

Feeding Ecology Of Black Sea Bass Centropristis Striata On An Artificial Reef Off Virginia (Perciforms: Serranidae), Ping K. Chee

OES Theses and Dissertations

The feeding ecology of the black sea bass, Centropristis striata, associated with artificial reefs shows seasonal and size-related changes. Monthly collections totaling 520 black sea bass taken from an artificial reef near the Chesapeake Light Tower, Virginia, between August 1975 and May 1976, were analyzed for food habits as revealed by number, volume, frequency of occurrence and a modified Index of Relative Importance.

The black sea bass feeds on the artificial reef as well as the adjacent areas. When food was abundant on the reef, food items from the reef and the surrounding area were consumed. Upon depletion of the …

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 …

A Comparative Study Of A Salt Water Impoundment With Its Adjacent Tidal Creek Pertinent To Culture Of Crassostrea Virginica (Gmelin), William D. Anderson Iii

OES Theses and Dissertations

Certain physical, chemical and biological characteristics associated with the culture of subtidal Crassostrea virginica were assessed in a salt water impoundment and its adjacent tidal feeder creek. Large seed oysters (initial y = 57.3 mm) were transferred from a somewhat polluted estuary of Charleston Harbor to floating, mid-water, and bottom hardware cloth trays (200/tray) in a four hectare pond. Identical trays at comparable depths were placed in the tidal creek and each location was sampled monthly for growth and survival. Surface and bottom water samples were collected weekly throughout the study and hourly during four seasonal 25 hour stations. Standard …

Seasonal Distribution And The Retention Of Some Decapod Crustacean Larvae Within The Chesapeake Bay, Virginia, Joseph William Goy

OES Theses and Dissertations

Planktonic stages or 45 genera and species or decapod larvae were identified and staged from samples taken over a three year period in the lower portion and entrance area or Chesapeake Bay. The distribution of each larval stage of the decapod crustaceans found in the bay was determined and from this, the extent of the respective breeding season was deduced. In 1975, samples were taken monthly from stations along a transect at the baymouth, both at the surface and bottom. Two stations were also occupied over the tidal cycle in daylight and darkness. Evidence is presented that larvae of some …

Numerical Simulation Of Thermohaline Convection In The Mixed Layer Of The Ocean, Victor Eli Delnore

OES Theses and Dissertations

The intradiumal heating and cooling cycle of the mixed layer of a tropical ocean is investigated through the use of a pseudo-two-dimensional numerical model. Particular emphasis is given to two-component diffusion resulting from dynamic instabilities in the water column. The conservation equations for salt and heat include the effects of solar heating, horizontal advectlon, and turbulent fluxes at the sea surface, while wind mixing enter through the use of depth-dependent eddy diffusion coefficients resulting from the wave-orbital shear model of KitaigorodsldLy. All inputs are treated as functions of time-of-day, or calculated via the bulk aerodynamic method.

The entrainment fluxes of …

The Effect Of 4-Chlororesorcinol On The Growth Potential Of Dunaliella Tertiolecta Butcher (Dun Clone), John Anthony Chigges

OES Theses and Dissertations

Jolley (1973) identified and quantified 4-chlororesorcinol at the 1.2 μg/1 level in secondary treated sewage effluent as one of 17 stable organochlorine compounds. The present report presents the first data on the effect of 4-chlororesorcinol on the growth potential of the marine phytoplankter, Dunaliella tertiolecta Butcher (Dun clone).

The assay method used herein was that of the Marine Algal Assay Procedure: Bottle Test (EPA, 1974). An algal culture chamber was constructed capable of providing controlled temperature (18 ± 2°C) and light (400-500 ft-c) conditions. Four parameters were used to describe the growth response of D. tertiolecta including maximum specific growth …

A Numerical Model For The Prediction Of Tides And Tidal Currents In The Lafayette River, Norfolk, Virginia, G. Mcallister Sisson

OES Theses and Dissertations

A prediction technique for tidal heights and currents in the Lafayette River of Norfolk, Virginia has been formulated and tested by the implementation of a two-dimensional numerical model employing the Navier-Stokes momentum equations and conservation of mass. The model operates on a spatially-fixed rectangular grid system by utilizing a multi-operation finite difference scheme which employs implicit and explicit solutions to the aforementioned equations. Forces due to bottom friction and Coriolis are taken into account. The only open boundary considered in the model is the river mouth, across which tidal height is specified temporally. Collected tidal height and current data at …

Test Variation In The Sand Dollar, Mellita Quinquiesperforata (Leske), George Glynn Rountree

OES Theses and Dissertations

Mellita quinguiesperforata is a common member of the benthos along the eastern coast of North America. This study considers variation of the test within the species, specifically: 1) variation in test weight, 2) variation in the length-width relationship, and 3) the average number of pore pairs in the ambulacral petals.

A total of 844 sand dollars from three localities was utilized: 1) Pass-a-Grill Beach, St. Petersburg, Florida,2) Bird Shoal, Beaufort, North Carolina, and 3) Fisherman Island, Virginia.

Animals were measured for length and width and the dry weight determined. Prediction equations for the size-weight relat1onships were computed for the three …

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 …

The Natural History Of The Naked Goby Gobiosoma Bosci (Perciformes: Gobiidae), Leonard L. Nero

OES Theses and Dissertations

The purpose of this study was to contribute to the knowledge of re ­ production, growth, age, abundance, habitat preference, feeding habit and behavior of the naked goby, Gobiosoma Bosci.

Monthly collections were made from January through December. 1974 in Deary Cove a apart of the Lynnhaven estuary, Virginia Beach, Virginia. All fish were measured and sexed in the field.

Most were returned to the population, the remainder. were removed for food habit analyses, determination of fecundity, degree of gonadal maturity and aging. Habitat­ preference and abundance were determined in the field.

Gobiosoma Bosci appears to be an annual …

Dynamics And Sedimentology Of Inner Middle Ground - Nine Foot Shoal, Chesapeake Bay, Virginia, Mitchell Alan Granat

OES Theses and Dissertations

The historical, hydrodynamic, and sedimentological development of Inner Middle Ground - Nine Foot Shoal indicates that it is presently in quasi-equilibrium with mutually evasive ebb and flood tidal currents. Bathymetric comparisons among six surveys taken during the past 122 years depict development of the shoal from two linear sand bodies to its present double parabolic morphology. Circulation paths are proposed for each survey.

Information from eight current meter stations on and adjacent to Inner Middle Ground - Nine Foot Shoal were used to determine near-surface and near-bottom tidal current asymmetries and directions. The concepts of bathymetrically diverted currents and mutual …

Microbenthic Algal Production Of An Intertidal Sandflat In Little Creek Harbor, Virginia Beach, Virginia, Clayton Barry Shedrow

OES Theses and Dissertations

Estimated annual net microbenthic algal production of an intertidal sandflat on Little Creek Inlet, Virginia Beach, Virginia, was 105 g C/m². Seasonally, primary production was greatest during the summer and fall periods (38 and 49 g C/m², respectively). Productivity was found to vary directly with water temperature and standing crop of benthic diatoms, and inversely with incident solar radiation and standing crops of sedimentary chlorophyll 'a' and 'c'. Orthophosphate and nitrate-N appeared to be limiting factors, nitrate-N more so than orthophosphate. Mean annual net photosynthetic efficiency (based upon total light) for the microphytobenthic community was 0.09%. …

Urbanization And Environmental Change In Lynnhaven Estuary, Don W. Oswalt

OES Theses and Dissertations

The very minimal amounts of available urbanization data demonstrate that the number of residential dwellings in the Lynnhaven drainage basin increased sharply in the late 1950’s and early 1960's, and that the 1970 basin population density value of 1981 people per square mile is larger than all the burrough density values, except for the Virginia Beach burrough. Due to a lack of data, only qualitative changes in Lynnhaven’s marine environment can be noted. There is a strong suggestion of an increase in amounts of urban storm water run-off into Lynnhaven since 1937. A considerable amount of siltation has occurred since …

The Analysis Of Volatile Organic Compounds In The Southern Chesapeake Bay, Virginia By Gas Chromatography/Mass Spectrometry, James D. Haluska

OES Theses and Dissertations

Sea-water samples from the Norfolk, Virginia area were analyzed for trace volatile organic compounds by helium sparging. Contents of the trap were injected into a gas chromatograph/mass spectrometer. Analysis of the trap contents indicated the presence of aliphatic and olef1nic hydrocarbons containing up to six carbon atoms and eight halogenated compounds of up to two carbon atoms in length. The halogenated compounds which were identified were dichlorofluoromethane, trichlorotrifluoroethane, carbon tetrachloride, chloroform, trichloroethane (2 isomers) bromodichloromethane, and chlorotrifluoroethylene. The

relative concentrations of volatile organic compounds generally tended to increase in samples collected from water prone to urban environmental pressures. All eight …

Heavy Mineral Distribution In The Lower Chesapeake Bay, Virginia, Frances Firek

OES Theses and Dissertations

Heavy minerals from 195 bottom sediment samples of the lower Chesapeake Bay, Virginia have been studied. In comparison with other areas such as the Gulf of Mexico, qualitative and qualitative mineralogical variations were subdued, because of the absence of widely divergent source areas. The effect of present-day drainage system on the mineralogical distribution patterns is not clear, largely because of the complex Pleistocene history of the study area.

Seven geographic provinces were defined and treated statistically. An analysis of variance was conducted on the seven provinces. The more significant mineral species from the study area are zircon, hornblende, pyroxene, and …

Quantitative And Qualitative Seasonal Analysis Of The Surface Zooplankton Of Magothy Bay, Virginia, Malcom E. Browne

OES Theses and Dissertations

No abstract provided.

Feeding And Food Preferences By Three Sympatric Species Of Cyprinodontid Fishes, Lawrence J. Baer

OES Theses and Dissertations

The feeding and food utilization by three sympatric species of cyprinodontid fishes was examined using a modified Ivlev Electivity Co-efficient. Results indicated that although Fundulus heteroalitus and Fundulus majalis are sympatric in the area examined,their usage of the available food source varied noticeably. The third investigated species, Cyprinodon variegatus, fed mainly upon a vegetal detritus food source varied by the consumption of invertebrate and vertebrate food items. Slight intra-specific variances of diet between crespuscular periods was also discussed.

Phycosociology Of The Estuarine Eulittoral Of Smith Island Virginia: A Quantitative Approach To Seasonal Periodicity, William M. Willis

OES Theses and Dissertations

Seasonal periodicity of benthic algae of the estuarine eulittoral of Smith Island, Virginia, (37°07’55” N, 75°55’ W), has been investigated on a qualitative and quantitative basis. Forty-three taxa of benthic eucaryiotic algae were found to be present; of these, twenty-one were quantitatively significant at least once during the course of the study. Five species represent additions to the Virginia flora, and, at the same time, also represent southern extensions of the known U.S. east coast range. The range of three other species has been extended, though they are not new to Virginia.

Review of the literature suggests two models of …

Food And Feeding Of Fishes From Magothy Bay, Virginia, Joseph J. Kimmel

OES Theses and Dissertations

No abstract provided.

Investigation Of The Halocline Structure In Lower Chesapeake Bay, Samuel Bowen Heltzel

OES Theses and Dissertations

A portion of the Chesapeake Bay from 37°20’N latitude to the entrance was investigated to determine the halocline structure, the effects on this structure through the tidal sequence, and seasonal variations. A determination of the stage of slack water during which maximum extension of the halocline occurred was also made. This was accomplished by looking at the salinity distribution at the halocline upper limit, the mean depth to the halocline, and seasonal salinity contours drawn for tidal increments. By comparing salinity/depth gradients and salinity-depth vertical profiles, an attempt was made to relate seasonal and tidal variations to the halocline structure. …

A Seasonal Distributional Survey Of The Epiphytic Diatoms Of The Outer Banks Region Of North Carolina With Respect To Temperature And Salinity, Charles Welles Belin Jr.

OES Theses and Dissertations

This study was initiated to investigate epiphytic diatoms at selected stations along the North Carolina coast and bay region. The relationships between these organisms and the season of the year and salinity and temperature of the water in which they were found are considered. The special affinity between the epiphytic diatoms and their host plants is also discussed. The specific data were analyzed statistically via linear correlation coefficients, graphs of least squares-best fit, and multiple linear regression analysis.

From the statistical tests, it was found that the mean number of epiphytic diatoms shows a significant multiple linear regression with respect …

Morphologic Time Series From A Submarine Sand Ridge On The South Virginia Coast, John F. Mchone Jr.

OES Theses and Dissertations

Submarine sand ridges several km long locally merge southward into the U. S. Atlantic coastline. Shallow (< 8m) observations of -such a ridge at False Cape, Virginia, favor a modern hydraulic origin. Time series maps show the ridge to be paralleled by a landward trough of approximately equal volume. Ridge flanks are usually steeper on the trough side.

Northeasterly winds and waves generate a coast-parallel current which funnels southward into the trough scouring it out and providing sediments for ridge aggradation. The current may be organized as a helical flow cell or cells. Bottom currents converge southward along the ridge crest causing landward transport of traction load along the crest. The trough current eventually breaches the confining ridge at the head of the trough, cutting saddles with steeper seaward slopes and producing outlying sediment fans.

The ridge and trough rest obliquely …