Physical Sciences and Mathematics Commons^™

Is Growth Of Eelgrass Nitrogen Limited? A Numerical Simulation Of The Effects Of Light And Nitrogen On The Growth Dynamics Of Zostera Marina, Richard C. Zimmerman, Robert D. Smith, Randall S. Alberte

OES Faculty Publications

A numerical model of nitrogen uptake and growth was developed for the temperate seagrass Zostera marina L. Goals were to evaluate the relative effects of light and nitrogen availability on nitrogen uptake and partitioning between leaf and root tissue, and to estimate nitrogen concentrations in the sedment and water column required to saturate growth. Steady-state predictions are quite robust with respect to a range of parameter values justified by available data The calculations indicated that roots are probably more important in overall nitrogen acquisition in most light and nitrogen environments encountered in situ, but may contribute less than 50 …

Primary Production And Temporal Variation In The Macrophytic Community Of A Tidal Freshwater Swamp, Bryan Keith Fowler

Dissertations, Theses, and Masters Projects

No abstract provided.

System Response Of A Nourished Beach In A Low-Energy Estuarine Environment, Gloucester Point, Virginia, Tracy Eanes Skrabal

Dissertations, Theses, and Masters Projects

No abstract provided.

Studies Of Pipefish Foraging In Simulated Seagrass Habitats, Clifford H. Ryer

Dissertations, Theses, and Masters Projects

Laboratory experiments determined the effects of two levels of habitat complexity upon pipefish (Syngnathus fuscus) foraging for amphipods. Habitats were composed of equal densities of either narrow (low complexity) or wide (high complexity) leafed artificial seagrass. The response to habitat, as measured by rate of encounter with amphipods, probability of attack after encounter, probability of success after attack, and overall rate of amphipod consumption, was determined for combinations of two fish size classes and three amphipod size classes. Small fish did not experience visually inhibitive effects in either habitat, while large fish had their visual fields impinged upon in the …

The Respiratory Response Of Busycon Canaliculatum (L) To Seasonal Variation Of Water Temperature, Salinity, And Oxygen, Harry Gregory Polites

Dissertations, Theses, and Masters Projects

No abstract provided.

The Geochemistry Of Interstitial Water For A Sediment Core From The Indian River Lagoon, Florida, Deyu Gu, Nenad Iricanin, John H. Trefry

Ocean Engineering and Marine Sciences Faculty Publications

Chemical results for interstitial water from organic-rich sediments in the Indian River Lagoon, Florida, show a classic picture of biogeochemical reactions in anoxic environments. Interstitial nitrate was depleted throughout the sediment column and complete sulfate reduction was observed at a depth of <9 cm below the seawater-sediment interface. Interstitial water chlorinity decreased sharply with depth suggesting subsurface occurrence or intrusion of groundwater. Ammonia, phosphate and silica concentrations were high showing significant nutrient regeneration. Dissolved sulfide levels were also high and play a primary role in controlling interstitial water metal concentrations.

Field Measurements Of Tidal Currents, I664 Tunnel Axis, Hampton Roads, Virginia : A Report To Morrison-Knudsen/Interbeton, Physical Oceanography Division, Virginia Institute Of Marine Science

Reports

Currents in the region of Newport News Point of the James River were measured at the request of Morrison-Knudsen/Interbeton to examine maximum flood and ebb values during spring tides and determine first order relationships of current strengths and phase lags between this region and Chesapeake Bay Entrance predictions.

Spatial And Temporal Variation Of Snow Accumulation In The Central Karakoram, Northern Pakistan, Cameron Parker Wake

Theses and Dissertations (Comprehensive)

Runoff from the Upper Indus Basin depends upon snowfall at high elevations in the northern mountains of Pakistan. However, very little is known concerning the amount of snowfall in the major source area, the high Karakoram, or its spatial and temporal distribution. Glaciers contain well preserved records of snow accumulation and provide a unique tool for retrieving data. A number of studies on temperate and tropical glaciers indicate that variations in chemical content and microparticle concentrations delineates seasonal stratigraphy. In addition, the chemical record of the snowpack can usually be used to determine the source of precipitation. Field work in …

Plume Monitoring Of Rappahannock And York Spit Channels, Baltimore Harbor And Channels: Phase 1, M. Nichols, R. J. Diaz, Et Al

Reports

A major element and concern necessary for evaluating the environmental impact of dredging operations is the dispersion of finegrained dredged material. The turbid plume generated by draghead agitation and by overflow processes from a hopper dredge can dictate the degree of potential adverse effects. Under certain environmental and aesthetic circumstances control of the plume may be advisable. Although turbid plumes produced by open water disposal operations have been evaluated in many investigations (e.g. Barnard. 1978). detailed field assessments of plumes produced by hopper dredging operations are scarce.

Spatial And Temporal Characteristics Of Surface Air Temperature For Portland, Oregon, Li-Min Yang

Dissertations and Theses

This study examines the spatial and temporal characteristics of the surface air temperature in Portland, Oregon. Spatial temperature patterns indicate that the dominant control factors on seasonal temperature distribution are local topography, elevation, and urban-rural differences in surface structure. A heat island exists in the Portland area; the intensity of the heat island rang€s from 4° to 10° F, and varies throughout the year. The strongest heat island is found in the July minimum temperature. Temperature distribution in Portland and the adjacent area is affected by winds and rainy conditions, but less influenced under overcast skies. The long-term temperature over …

Shoreward Intrusion Of Upper Gulf Stream Water Onto The United States Southeastern Continental Shelf, Lie-Yauw Oey, Larry P. Atkinson, Jackson O. Blanton

CCPO Publications

In winter, cooling of the South Atlantic Bight continental shelf water results in higher density in the middle shelf region relative to the shelf-break region where the western flank of the Gulf Stream flows. Shoreward, estuarine-like intrusion of the upper Gulf Stream water in the presence of such a positive onshore density gradient is then possible through advective processes triggered either by the meander of the Stream or onshore Ekman transports by southward wind stresses. Repeated cross-shelf hydrographic transects were conducted from 10 January through 30 January 1986 to more closely study this intrusion process. These observations show many features …

Optimal Groundwater Mining Methods, Richard C. Peralta, Krzysztof G. Kowalski

Technical Reports

No abstract provided.

Slack-Water Deposits And The Magnitude And Frequency Of Flash Floods, Eastern Kentucky, Russell G. Shepherd, Lisa K. Bienkowski

KWRRI Research Reports

The potential for predicting flood magnitude and frequency using sediments deposited in backwater areas during flash floods was investigated on the Cumberland Plateau of eastern Kentucky, a region n9torious for flash flooding. Slack-water deposits are abundant in the area at tributary mouths and bedrock channel expansions. They are identifiable on geologic quandrangle maps, and are locally good potential indicators of maximum flood-crest elevations. However, in this humid region, flash floods could not be distinguished from non-flash floods using slack-water sedimentology.

The results from the slack-water deposits studied indicate that they offer limited potential for predicting flash floods because 1) intense …

Hydrographic Data From The Wolftrap Section, 1982-1983, L. M. Huzzey, J. M. Brubaker

Reports

No abstract provided.

Mesoscale Hydrographic Variability In The Vicinity Of Points Conception And Arguello During April May 1983: The Opus 1983 Experiment, Larry P. Atkinson, Kenneth H. Brink, Russ E. Davis, Burton H. Jones, Theresa Paluszkiewicz, David W. Stuart

CCPO Publications

In April and May 1983, interdisciplinary oceanographic observations were made of upwelling events in the Point Conception area off southern California. The principal objective was to observe the structure and time dependence of the upwelling system. To accomplish this, two ships, two aircraft, moorings, drogues, and satellite imagery were all included in the observational effort. During the intensive measurement period three main upwelling events and two intervening relaxation or downwelling intervals were sampled during what was a period of overall longer-term sea surface warming. Surface temperatures during upwelling were as low as 10.5°C in the upwelling center between Point Arguello …

Cliff-Height And Slope-Angle Relationships In A Chronosequence Of Quaternary Marine Terraces, San Clemente Island, California, Russell Crittenden, Daniel R. Muhs

United States Geological Survey: Staff Publications

Zusammenfassung. Eine Abfolge quartarer Strandterrassen auf ~an Clemente Island, Kalifornien, liefert einen Rahmen fur die quantitative Analyse der Anderungen an vom Meer verlassenen Kustenkliffen als Funktion der Zeit. Es wurde eine Abschatzung der Anwendbarkeit von BUCKNAM & ANDERSON (1979) log-lin~arer Beziehung zwischen Wandhohe und Hangwinkel durchgefuhrt, indem Brandungskliffhohe und maximale Hangwinkel verwendet wurden. Die Ergebnisse zeigen eine regelhafte Zunahme des Hangwinkels mit dem Logarithmus der Kliffhohe, und Kliffe einer bestimmten Hohe zeigen m,it der Zeit eine Abnahmedes maximalen Hangwinkels. 1m ganzen waren die Relationen schwacher als fur FluBterrassen und Bruchstufen in unverfestigten Materialen, aber die Methode kann wahrscheinlich verwendet werden, …

A Scientific Application For Remotely Operated Vehicles, Mark S. Gustafson

Marine Affairs Theses and Major Papers

Although Remotely Operated Vehicles (ROVs) have been employed in the underwater circuit since the mid-1990s, their impact upon the ocean community has not been felt until the past decade. The remotely operated vehicle (ROV) industry developed from the needs of the oil and gas community to find a cost efficient, and safe method of replacing man and manned submersibles underwater. However, marine scientists have been reluctant to accept this tool as part of their research inventory. The slowness of technological transfer stems from several issues: the lack of quantifiable results; the untried technology; and a lack of awareness. The objective …

A Histological Investigation Of The Larval Mandibular Organ In The Mud Crab Rhithropanopeus Harrisii (Gould) (Crustacea Decapoda Xanthidae), Lore Lynn Hantske

OES Theses and Dissertations

Mandibular organs of the mud crab, Rhithropanopeus harrisii (Gould) were histologically located and followed throughout the larval cycle to determine their role in metamorphosis. Specimens from each day of the four larval stages and the megalopa stage were embedded in paraffin, sectioned at 8 μm, stained and observed under the microscope for the mandibular organs. The organs were located in the mandibular area of second, third and fourth stage larvae. The organs were probably present in the first stage zoeae and in the megalopa stage, although the

techniques of the study were not sensitive enough to observe them. The …

Environmental Factors Affecting Nocturnal Migrations Of Macrobenthos, C. Timothy Morris

Biological Sciences Theses & Dissertations

Nocturnally dispersing macrobenthic invertebrates of the Lafayette River, Norfolk, Virginia were collected from September 4 to October 4, 1982 to determine environmental factors affecting migrations. A total of 55 taxa were identified from 325 surface and bottom nocturnal plankton tows. Peracaridan crustaceans were the dominant (99.0% of the total density) group collected. Six of the commonly collected species showed a significant (P

Local Water Resource Information Management System, David G. Parker, Sandra C. Parker

Technical Reports

A Beaver Lake water quality database has been designed as a relational database. It has been implemented using software called R:base 5000, a system available for microcomputers using MS- or PC- DOS operating systems. The data in the database include that concerned with the author(s), title, date of publication, agency doing the study, agency funding the study and complete reference for the document. Other aspects of the database are designed to allow retrievals based on any author, study dates, parameters measured and keywords.

Evaluation Of Packed Towers For Removing Volatile Organics From Surface Waters, James W. Moore

Technical Reports

This study analyzes the potential of packed tower aeration as a remedial treatment process for the removal of trace organics on either an acute or chronic basis. Both pilot-scale installations of the packed tower process were reviewed. Included are basic modeling considerations for the removal of volatile trace organics from raw water. Included also is an assessment of the state of the technology as applied to air stripping of water.

Long-Term Effects Of Tillage On The Retention And Transport Of Soil Water, H. D. Scott, L. S. Wood, W. M. Miley

Technical Reports

Quantitative measurements were made of the physical and chemical properties of two virgin prairie soils, Crowley and Jay, that remain in their native Arkansas environments and of similar soils that had been tilled extensively. Comparisons were made of soil properties at several depths. When compared with the tilled soils the virgin soils had higher organic matter contents, saturated hydraulic conductivities and water retained at several applied pressures. Bulk densities and hydraulic resistances were lower in the virgin soils. For the Crowley silt loam, values of pH and elemental contents of the virgin soil were higher than those of the tilled …

The Behavior Of Soluble Salt In Sharkey Clay- Ii, J. T. Gilmour, R. E. Baser, H. D. Scott, J. A. Ferguson

Technical Reports

Soluble salts have been shown to accumulate in Arkansas soils in sufficient quantities to impair crop plant growth. The major objective of this study was to describe the behavior of soluble chloride salt over long time periods in Sharkey clay - a major Mississippi Delta soil. Prior to flooding rice, leaching of chloride in response to rainfall was observed. The inclusion of a sandy subsoil layer reduced this effect presumably by limiting downward movement of water under unsaturated conditions. No lateral movement of the chloride salt was found during the period prior to flooding. Removal of soluble chloride salts from …

Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends- Ii, Richard L. Meyer

Technical Reports

A database of the algae of Arkansas has been established by the use of a relational database management system (dBase III). The system was chosen to be readily available for microcomputers using MS and PC-DOS. The database contains taxonomic fields from division through variety, synonomy, authors, starting date and definitive descriptive source. The data is cross-referenced by ecoregion, community and subcommunity. The database contains nearly 1,500 taxonomic records in all division and classes of freshwater algae. These data are sortable by any of the included parameters. The data have been used to initiate the publication of the algal flora of …

Algal Growth Potentials And Heavy Metal Concentrations Of The Primary Streams To Upper Beaver Lake, Richard L. Meyer, W. Reed Green, Kenneth F. Steele, Diana Wickliff

Technical Reports

Meyer and Green (1984) demonstrated the probable inhibition of algal growth potential by heavy metals in upper Beaver Lake. Upper Beaver Lake receives water from three tributaries. One contains a small reservoir and the combined streams receive sewage input. Collections were made approximately monthly at eight sites for the Algal Assay Bottle Test (AABT) and heavy metal analysis. In general, AABT results indicated that the collections above the sewage lnput were phosphorus limited while those below were nitrogen or combined nitrogen and phosphorus limited. Growth inhibition occurred during summer and early fall at various sites with greater inhibition at the …

Fishermen's Personal Injuries: A New Look At The Fishing Industry's Insurance Crisis, Frederic M. Fairfield

Marine Affairs Theses and Major Papers

Increasing cost and shrinking availability of marine insurance have resulted in serious problems for broad sectors of the nation's commercial fishing fleet. Sharp reductions in the availability of Protection and Indemnity coverage have idled vessels nationwide regardless of individual safety records. The causes of the current problem are varied and numerous, with significant roles played by the fishing industry, the regulatory framework, the insurance industry, and the legal remedies involved. Ultimately, the solution will require both a reduction in the frequency of fishermen's injuries and modifications to the present compensation system, reducing insurance costs while security equitable compensation for the …

As Assessment Of The Fisheries Research Program Of The National Marine Fisheries Service, Gary Page Bulmer

Marine Affairs Theses and Major Papers

The nation's fishery management regime has three primary sets of players: the scientific advisors, the managers, and the fishermen. The advisors include federal agencies, state agencies, universities, regional and interstate bodies, and international bodies. The National Marie Fisheries Service (NMFS) has the lead role as scientific advisor. As used here "management" is defined broadly to include the instructions and funding that the researchers are given. "Fisheries research" is also defined broadly for the purposes of this paper. It means the collection of any biological, economic, or social information which is relevant to fisheries management.

New Genera And Species Of The Megaluropus Group (Amphipoda, Megaluropidae) From American Seas, James Darwin Thomas, J. L. Barnard

Marine & Environmental Sciences Faculty Articles

The species of the Megaluropus group, here placed in three genera, two of which are described as new, are reported from the Caribbean Sea and the eastern Pacific Ocean. The west African Megaluropus longimerusSchellenberg is redescribed and a lectotype chosen. It is placed in the new genus Gibberosus which otherwise has three American species, G. falciformis, G. myersi, and a new species, G. devaneyi. Megaluropus is now confined to the Old World. A second new genus from the New World, Resupinus, is described to include R. visendus and two new species, R. spinicaudatus and R. coloni …

Two Species Of Hornellia (Subgenus Metaceradocus) From The Florida Keys And Belize (Amphipoda, Melphidippoidea), James Darwin Thomas, J. L. Barnard

Marine & Environmental Sciences Faculty Articles

Hornellia (Metaceradocus) atlanticus, a new species from Belize, related to M. occidentalis, an eastern Pacific species, is reported from the Caribbean Sea and a morphologically remote new species, M. tequestae, is described from the Florida Keys.

Patterns Of Diurnal Vertical Distribution And Dispersal-Recruitment Mechanisms Of Decapod Crustacean Larvae And Postlarvae In The Chesapeake Bay, Virginia And Adjacent Offshore Waters, Robert Copeland Maris

OES Theses and Dissertations

Larval dispersal and subsequent postlarval recruitment are extremely significant processes affecting the maintenance of ecologically and economically important populations of decapod crustaceans. Vertical positioning in the water column plays a major role in the particular strategies of retention or expulsion with immigration.

The present study was undertaken to investigate variations in vertical distribution according to temporal (diurnal), spatial (estuarine, transition, oceanic), ontogenetic (larval stages, postlarvae) and various environmental factors (especially light, temperature, salinity and tides). Also, effects of vertical positioning on dispersal-recruitment were examined.

Three stations were established for the present study: York River mouth (estuarine) (37°12'N, 76°16'W); Chesapeake Bay …