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Full-Text Articles in Life Sciences

Plant Species Of The Virginia Coastal Plain Flora That Are Disjunct From The Mountains: Their Distribution, Abundance And Substrate Selectivity, Leah E. Mcdonald Jan 2000

Plant Species Of The Virginia Coastal Plain Flora That Are Disjunct From The Mountains: Their Distribution, Abundance And Substrate Selectivity, Leah E. Mcdonald

Dissertations, Theses, and Masters Projects

No abstract provided.


Characterization Of Iron-Bearing Solids Used By Naturally-Occurring Microbes In The Anaerobic Degradation Of Hydrocarbons, David C. Powell Jan 2000

Characterization Of Iron-Bearing Solids Used By Naturally-Occurring Microbes In The Anaerobic Degradation Of Hydrocarbons, David C. Powell

Dissertations, Theses, and Masters Projects

No abstract provided.


Organic Matter Composition Of Sediments And The History Of Eutrophication And Anoxia In The Mesohaline Chesapeake Bay, Andrew R. Zimmerman Jan 2000

Organic Matter Composition Of Sediments And The History Of Eutrophication And Anoxia In The Mesohaline Chesapeake Bay, Andrew R. Zimmerman

Dissertations, Theses, and Masters Projects

To evaluate the effects of anthropogenic alteration of the Chesapeake Bay (CB) watershed since European settlement, the historical progression of eutrophication and anoxia in the mesohaline region of CB was reconstructed. Lipid biomarker and carbon and nitrogen stable isotopic and elemental composition of CB surficial sediments were examined seasonally in order to identify the present sources of organic matter to CB sediments and the processes controlling their distribution. Temporal variability in surficial sediment composition could be linked to seasonal changes in phytoplankton community composition and biomass while spatial variation was dominated by the delivery of alloclithonous versus autochthonous sources of ...


Bioremediation Of Tributyltin Contaminated Sediment Using Spartina Alterniflora In A Created Tidal Wetland, Britt-Anne Anderson Jan 2000

Bioremediation Of Tributyltin Contaminated Sediment Using Spartina Alterniflora In A Created Tidal Wetland, Britt-Anne Anderson

Dissertations, Theses, and Masters Projects

No abstract provided.


The Human Factor In Size Selectivity In The Sea Scallop, Placopecten Magellanicus Fishery, Arman O. Kaltayev Jan 2000

The Human Factor In Size Selectivity In The Sea Scallop, Placopecten Magellanicus Fishery, Arman O. Kaltayev

Dissertations, Theses, and Masters Projects

No abstract provided.


Application Of The Shoreline Instability Model Along The Western Side Of The Chesapeake Bay, Va, Kevin G. Skunda Jan 2000

Application Of The Shoreline Instability Model Along The Western Side Of The Chesapeake Bay, Va, Kevin G. Skunda

Dissertations, Theses, and Masters Projects

No abstract provided.


Maturation And Repeat Spawning By American Shad In The York River, Virginia, Kristin L. Maki Jan 2000

Maturation And Repeat Spawning By American Shad In The York River, Virginia, Kristin L. Maki

Dissertations, Theses, and Masters Projects

No abstract provided.


Population Dynamics Of The Smooth Dogfish, Mustelus Canis, In The Northwest Atlantic, Christina L. Conrath Jan 2000

Population Dynamics Of The Smooth Dogfish, Mustelus Canis, In The Northwest Atlantic, Christina L. Conrath

Dissertations, Theses, and Masters Projects

No abstract provided.


Seasonal Residence, Movement, And Activity Patterns Of Adult Tautog, Tautoga Onitis, In Lower Chesapeake Bay, Michael D. Arendt Jan 2000

Seasonal Residence, Movement, And Activity Patterns Of Adult Tautog, Tautoga Onitis, In Lower Chesapeake Bay, Michael D. Arendt

Dissertations, Theses, and Masters Projects

No abstract provided.


Osteology, Phylogeny, And Biogeography Of The Marine Fish Family Ephippidae (Perciformes, Acanthuroidei), With Comments On Sister Group Relationships, Martin Ray Cavalluzzi Jan 2000

Osteology, Phylogeny, And Biogeography Of The Marine Fish Family Ephippidae (Perciformes, Acanthuroidei), With Comments On Sister Group Relationships, Martin Ray Cavalluzzi

Dissertations, Theses, and Masters Projects

The marine fish family Ephippidae comprises eight genera and 15 species of extant fishes. Spadefishes or batfishes inhabit nearshore tropical to temperate waters. They are almost circumglobal in distribution, with the highest diversity in the Indo-west Pacific and the lowest diversity in the east Pacific and west Atlantic. Fifty-nine potentially informative morphological characters, 10 outgroup taxa, and eight ingroup taxa (i.e., genera) were used to explore sister group hypotheses to the Ephippidae, as well as generate a phylogeny of the Ephippidae. Seven constraint tree analyses were utilized to examine various sister group hypotheses based on previous morphological and molecular ...


The Specific Immune Response In Rainbow Trout: Somatic Hypermutation And Vh Gene Utilization, Teresa D. Lewis Jan 2000

The Specific Immune Response In Rainbow Trout: Somatic Hypermutation And Vh Gene Utilization, Teresa D. Lewis

Dissertations, Theses, and Masters Projects

The study of antibody responses in prominent aquaculture species such as the rainbow trout, Oncorhynchus mykiss, can facilitate vaccine development and contribute to producing useful paradigms of adaptive immunity in lower vertebrates. Thus, it is essential to identify genes responsible for antibody responses. In the mouse model, hybridoma technology allows for the association of monoclonal antibodies possessing various affinities for antigen with specific VH sequences, gene family utilization, and other molecular events (i.e. somatic hypermutation) that occur during the specific immune response. The absence of a comparable hybridoma technology in piscine systems has limited similar studies of fish immunogenetics ...


Demographics, Production, And Benthic -Pelagic Coupling By The Suspension Feeding Polychaete Chaetopterus Pergamentaceus In The Lower Chesapeake Bay, Michelle Lynne Thompson Neubauer Jan 2000

Demographics, Production, And Benthic -Pelagic Coupling By The Suspension Feeding Polychaete Chaetopterus Pergamentaceus In The Lower Chesapeake Bay, Michelle Lynne Thompson Neubauer

Dissertations, Theses, and Masters Projects

For many shallow water environments, ecosystem function depends on the cycling and flow of materials and energy between benthic and pelagic subsystems. Benthic suspension feeders often are important links between the water column and sediment in coastal ecosystems. Populations of the suspension feeding polychaete Chaetopterus pergamentaceus (previously reported as Chaetopterus variopedatus) are widely distributed along the United States East Coast, ranging from New England to Florida. This species is a structurally and functionally important member of the lower Chesapeake Bay benthic community, where it has maintained stable populations for at least the last 15 years. Little is known regarding the ...


A Molecular Phylogeny Of The Sparidae (Perciformes: Percoidei), Thomas M. Orrell Jan 2000

A Molecular Phylogeny Of The Sparidae (Perciformes: Percoidei), Thomas M. Orrell

Dissertations, Theses, and Masters Projects

The Sparidae are a diverse group of over 110 marine species whose putative six subfamilies have been defined primarily on the basis of dentition and feeding type. Monophyly of the subfamilies has not been tested, nor have the phylogenetic relationships of all sparid genera been hypothesized. I used mitochondrial DNA sequences from the complete cytochrome b gene (1140 bp) and the partial 16S gene (621 bp) in independent and combined analyses to test the monophyly of the Sparidae, elucidate the inter-relationships of the 33 recognized genera of the Sparidae, test the validity of the six subfamilies of the Sparidae, and ...


Effects Of Polychlorinated Biphenyl Exposure On Development And Sexual Differentiation In Ranid Tadpoles, Mary J. Rybitski Jan 2000

Effects Of Polychlorinated Biphenyl Exposure On Development And Sexual Differentiation In Ranid Tadpoles, Mary J. Rybitski

Dissertations, Theses, and Masters Projects

The effects of AroclorRTM1242 exposure on developing amphibians were examined by exposing southern leopard frogs, Rana sphenocephala, to a contaminated diet throughout the larval period. Treatment groups consisted of an untreated control, a solvent control, 17beta-estradiol, and three PCB doses (10, 100, and 1000 mug/g). PCB accumulation and biotransformation were examined. Effects of PCB exposure on metamorphosis and sexual differentiation were assessed. PCB accumulation was not statistically different between the egg masses. Levels of PCBs in the tissues differed in a dose related manner. Within treatments, body weight appeared to be the major factor correlated with PCB concentration. Congener ...


Assessment Of Spawning And Nursery Habitat Suitability For American Shad (Alosa Sapidissima) In The Mattaponi And Pamunkey Rivers, Donna Marie Bilkovic Jan 2000

Assessment Of Spawning And Nursery Habitat Suitability For American Shad (Alosa Sapidissima) In The Mattaponi And Pamunkey Rivers, Donna Marie Bilkovic

Dissertations, Theses, and Masters Projects

Delineation of essential fish habitat is particularly difficult for migratory fish which utilize large expanses of habitat throughout their life history. This study's main objective was the development and evaluation of habitat assessment tools for the early life stages of American shad (Alosa sapidissima) in two coastal plain rivers. to accomplish this, shad spawning and larval nursery habitats were delineated in the Mattaponi and Pamunkey rivers using presence of eggs and larvae (1997--1999) as evidence of habitat use. A watershed habitat assessment protocol was developed and used to rate habitat based on hydrographic, physical habitat, shoreline and land use ...


Carbon Dynamics In A Tidal Freshwater Marsh, Scott C. Neubauer Jan 2000

Carbon Dynamics In A Tidal Freshwater Marsh, Scott C. Neubauer

Dissertations, Theses, and Masters Projects

The sources and fates of carbon in a tidal freshwater marsh (Sweet Hall marsh; Pamunkey River, Virginia) were determined to understand the role that these marshes play with respect to estuarine carbon cycling. A carbon gas flux model, based on measured carbon dioxide and methane fluxes, was developed to calculate annual rates of macrophyte and microalgal photosynthesis and community and belowground respiration. Because carbon fluxes out of marsh sediments may underestimate true belowground respiration if sediment-produced gases are transported through plant tissues, gross nitrogen mineralization was used as a proxy for belowground carbon respiration. Annual community respiration exceeded gross photosynthesis ...


The Role Of Stress In Determining Community Structure: Effects Of Hypoxia On An Estuarine Epifaunal Community, Alessandra Sagasti Jan 2000

The Role Of Stress In Determining Community Structure: Effects Of Hypoxia On An Estuarine Epifaunal Community, Alessandra Sagasti

Dissertations, Theses, and Masters Projects

Community models predict the effects of stress on community structure and processes. I tested the Menge and Sutherland 1987 model in an estuarine epifaunal community experiencing low oxygen stress, termed hypoxia. Epifauna, animals living on the surfaces of substrates, are ecologically important in many estuaries where hypoxia occurs, yet little is known about the effects of hypoxia on these communities. Epifauna formed dense communities in the York River, a tributary of the Chesapeake Bay, USA, despite frequent hypoxia. Abundance and species composition was similar in two areas of the river, even though the downstream study area often experienced lower oxygen ...


Synoptic Scale Climatic Forcing Of Multispecies Fish Recruitment Patterns In Chesapeake Bay, Robert J. Wood Jan 2000

Synoptic Scale Climatic Forcing Of Multispecies Fish Recruitment Patterns In Chesapeake Bay, Robert J. Wood

Dissertations, Theses, and Masters Projects

Five fishery independent data sets were used to investigate multispecies fish recruitment patterns in Chesapeake Bay (1966--1997). Despite differences in sampling gear, sampled habitat, collection methods, and sampling sites, the strongest multispecies recruitment patterns within each data set (revealed by separate principal components analyses) depict a negative relationship between recruitment of spring spawning anadromous fishes and fall-winter continental shelf spawning species. This pattern dominates both low and high frequency components of the multispecies data. Because these two species groups utilize freshwater and oligohaline reaches of the Bay and its tributaries as springtime nursery areas, this Chesapeake Bay Anadromous-Shelf Spawner (CBASS ...


Photosynthetic Response And Nutrient Uptake Dynamics Of Phytoplankton In The Ross Sea, Antarctica, Christina Marie Van Hilst Jan 2000

Photosynthetic Response And Nutrient Uptake Dynamics Of Phytoplankton In The Ross Sea, Antarctica, Christina Marie Van Hilst

Dissertations, Theses, and Masters Projects

No abstract provided.


The Habitat Utilization Of Juvenile Hawksbill Sea Turtles (Eretmochelys Imbricata) At Buck Island Reef National Monument, St Croix, U.S Virgin Islands, Roy A. Pemberton Jan 2000

The Habitat Utilization Of Juvenile Hawksbill Sea Turtles (Eretmochelys Imbricata) At Buck Island Reef National Monument, St Croix, U.S Virgin Islands, Roy A. Pemberton

Dissertations, Theses, and Masters Projects

No abstract provided.


Use Of A Digital Multispectral Video System And Spectroradiometer For Bottomland Hardwood Forest Remote Sensing: A Jurisdictional Boundary Accuracy Assessment And Radiance Examination, Jill E. Meyer Jan 2000

Use Of A Digital Multispectral Video System And Spectroradiometer For Bottomland Hardwood Forest Remote Sensing: A Jurisdictional Boundary Accuracy Assessment And Radiance Examination, Jill E. Meyer

Dissertations, Theses, and Masters Projects

No abstract provided.


A Framework For Construction And Analysis Of Juvenile Abundance Indices For American Shad (Alosa Sapidissima) In The York River, Virginia, Mary Lynn Aiken Jan 2000

A Framework For Construction And Analysis Of Juvenile Abundance Indices For American Shad (Alosa Sapidissima) In The York River, Virginia, Mary Lynn Aiken

Dissertations, Theses, and Masters Projects

No abstract provided.


Microgeographic Population Genetic Structure Of The Mummichog (Fundulus Heteroclitus L) Inhabiting An Industrialized Waterway, Luis Felipe Arzayus Jan 2000

Microgeographic Population Genetic Structure Of The Mummichog (Fundulus Heteroclitus L) Inhabiting An Industrialized Waterway, Luis Felipe Arzayus

Dissertations, Theses, and Masters Projects

No abstract provided.


Biology Of The Spotted Seatrout, Cynoscion Nebulosus, In The Chesapeake Bay Region, Thomas F. Ihde Jan 2000

Biology Of The Spotted Seatrout, Cynoscion Nebulosus, In The Chesapeake Bay Region, Thomas F. Ihde

Dissertations, Theses, and Masters Projects

No abstract provided.


An Investigation Of Hybridization Between Two Serranid Fishes, The Coney (Cephalopholis Fulva) And The Creole Fish (Paranthias Furcifer), Meredith A. Bostrom Jan 2000

An Investigation Of Hybridization Between Two Serranid Fishes, The Coney (Cephalopholis Fulva) And The Creole Fish (Paranthias Furcifer), Meredith A. Bostrom

Dissertations, Theses, and Masters Projects

No abstract provided.


Function And Regulation Of Alternative Isoforms Of The Transcription Factor Pax-5 During B Lymphocyte Differentiation, Marina A. Lowen Jan 2000

Function And Regulation Of Alternative Isoforms Of The Transcription Factor Pax-5 During B Lymphocyte Differentiation, Marina A. Lowen

Dissertations, Theses, and Masters Projects

No abstract provided.


Suboptimal Foraging Behavior By Herring Gulls, Jennifer R. Gamble Jan 2000

Suboptimal Foraging Behavior By Herring Gulls, Jennifer R. Gamble

Dissertations, Theses, and Masters Projects

No abstract provided.


Stopover Ecology Of The Blackpoll Warbler, Dendroica Striata, During Spring Migration On The Coastal Plain Of Virginia, Magill Weber Jan 2000

Stopover Ecology Of The Blackpoll Warbler, Dendroica Striata, During Spring Migration On The Coastal Plain Of Virginia, Magill Weber

Dissertations, Theses, and Masters Projects

No abstract provided.


Application Of Genetic Markers To Provide Species Identification And Define Stock Structure: Analyses Of Selected Marine Fishes Of The Mid -Atlantic Bight, Jan F. Cordes Jan 2000

Application Of Genetic Markers To Provide Species Identification And Define Stock Structure: Analyses Of Selected Marine Fishes Of The Mid -Atlantic Bight, Jan F. Cordes

Dissertations, Theses, and Masters Projects

Molecular markers and techniques were employed to develop a genetic key for the forensic identification of 16 species of Chesapeake Bay sportfishes and to investigate the stock structure of one of those species, the weakfish Cynoscion regalis. Regions within the ATP synthetase 6 (ATPase 6), Cytochrome b , cytochrome c oxidase I, NADH dehydrogenase 4 (ND4), and 12S/16S ribosomal RNA mitochondrial genes were amplified using the polymerase chain reaction (PCR) and digested with a bank of restriction endonucleases to find a genetic marker that exhibited complete interspecific differentiation and low intraspecific variation. Complete separation of all sixteen species was accomplished ...


Ecological Interactions Between Benthic Oyster Reef Fishes And Oysters, Juliana Maria Harding Jan 2000

Ecological Interactions Between Benthic Oyster Reef Fishes And Oysters, Juliana Maria Harding

Dissertations, Theses, and Masters Projects

Restoration of oyster reef structures rehabilitates habitats and the multi-level ecological communities built on eastern oysters (Crassostrea virginica), the keystone species. Quantitative descriptions of ecological interactions within a habitat are required to delineate essential fish habitats for management and protection. Parallel development of primary (oysters) and secondary trophic levels (benthic fishes) offer an ecological metric of restoration progress over time. The interaction between larval oysters and larval fishes (e.g., Gobiosoma bosc, Chasmodes bosquianus) is quantitatively examined. Oyster settlement estimates for Palace Bar reef, Piankatank River, Virginia are of the same order of magnitude as field densities of recently settled ...