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Articles 1 - 17 of 17

Full-Text Articles in Life Sciences

Reproductive Attributes Of Polynoid Polychaetes From Hydrothermal Vents On The East Pacific Rise, Jessica Lynn Wallace Jan 2005

Reproductive Attributes Of Polynoid Polychaetes From Hydrothermal Vents On The East Pacific Rise, Jessica Lynn Wallace

Dissertations, Theses, and Masters Projects

No abstract provided.


Iron And Carbon Limitation Of Prokaryotic Growth In The Ocean, Jacques L. Oliver Jan 2005

Iron And Carbon Limitation Of Prokaryotic Growth In The Ocean, Jacques L. Oliver

Dissertations, Theses, and Masters Projects

Studies were undertaken to examine the roles of iron and carbon in modulating prokaryotic growth in the ocean. The context of the first study was an open-open iron fertilization experiment in the high nutrient, low chlorophyll (HNLC) regime in the Southern Ocean. The context of the second study was the oligotrophic, iron-replete, and organic carbon-limited northwest Sargasso Sea. Experimental sea water cultures were amended with an iron chelator, desferrioxamine B (DFOB), and other nutrients to examine the effects of iron and carbon limitation on growth. In the first study prokaryotic abundance, carbon production, and growth rate increased in response to ...


Regulation And Impact Of The Phytoplankton Assemblage Composition In The Southern Ocean, Jill A. Peloquin Jan 2005

Regulation And Impact Of The Phytoplankton Assemblage Composition In The Southern Ocean, Jill A. Peloquin

Dissertations, Theses, and Masters Projects

Southern Ocean waters have been identified as critical regions because of their potential to impact global climate as they play an integral role in oceanic overturning and circulation. They are also an area of deep and intermediate water formation and can potentially modulate atmospheric CO 2 concentrations. This project focuses on two regions that are seasonally limited by biologically available iron, the open HNLC Southern Ocean and the Ross Sea. The objective of this project was to determine how iron impacts the regulation of photosystem II and how the presence of particular phytoplankton species affects the ability of satellites to ...


Eye Pathologies Found In Several Decapod Crustaceans, Andrea M. Maniscalco Jan 2005

Eye Pathologies Found In Several Decapod Crustaceans, Andrea M. Maniscalco

Dissertations, Theses, and Masters Projects

No abstract provided.


Meiofauna Abundance And Distribution In Chesapeake Bay: Relationships With Environmental Stressors, Sediment Toxicity And Macrofauna, William J. Metcalfe Jan 2005

Meiofauna Abundance And Distribution In Chesapeake Bay: Relationships With Environmental Stressors, Sediment Toxicity And Macrofauna, William J. Metcalfe

Dissertations, Theses, and Masters Projects

Macrofauna-based biocriteria to assess impairment in aquatic communities are well-developed and have been widely accepted as useful for coastal monitoring programs worldwide. Meiofauna-based methods are not as well developed, but meiofauna are intimately associated with sediments through their life cycles and are functionally important. Thus, an understanding of meiofauna relationships with environmental quality is also important. Relationships between the abundance and composition of major meiofauna taxa for two shallow water habitat types (protected, with muddy sediment; exposed, with sandy sediment) were investigated along gradients associated with changing land use, sediment contamination and environmental stressors in Chesapeake Bay. Principal component analysis ...


Physiological Ecology Of The Cultured Hard Clam, Mercenaria Mercenaria: A Case Study In Cherrystone Inlet, Virginia, Elizabeth Darrow Condon Jan 2005

Physiological Ecology Of The Cultured Hard Clam, Mercenaria Mercenaria: A Case Study In Cherrystone Inlet, Virginia, Elizabeth Darrow Condon

Dissertations, Theses, and Masters Projects

No abstract provided.


Predator Management And Colonial Culture, 1600-1741: A Study In Historical Ecology, Samuel Taylor Elswick Jan 2005

Predator Management And Colonial Culture, 1600-1741: A Study In Historical Ecology, Samuel Taylor Elswick

Dissertations, Theses, and Masters Projects

No abstract provided.


Response To Selection Of Peromyscus Leucopus: Response Of Spermatogenesis And Reproductive Behavior To Selection On Gonadal Development In An Outbred Population Of White-Footed Mice (Peromyscus Leucopus), Kathleen Rathbun Sharp Jan 2005

Response To Selection Of Peromyscus Leucopus: Response Of Spermatogenesis And Reproductive Behavior To Selection On Gonadal Development In An Outbred Population Of White-Footed Mice (Peromyscus Leucopus), Kathleen Rathbun Sharp

Dissertations, Theses, and Masters Projects

No abstract provided.


Effects Of Human Disturbance On The Breeding Success Of Eastern Bluebirds (Sialia Sialis), Caitlin Rebecca Kight Jan 2005

Effects Of Human Disturbance On The Breeding Success Of Eastern Bluebirds (Sialia Sialis), Caitlin Rebecca Kight

Dissertations, Theses, and Masters Projects

No abstract provided.


Characteristics Of Vesicomyid Clams And Their Environment At The Blake Ridge Cold Seep, Taylor Perrine Heyl Jan 2005

Characteristics Of Vesicomyid Clams And Their Environment At The Blake Ridge Cold Seep, Taylor Perrine Heyl

Dissertations, Theses, and Masters Projects

No abstract provided.


Transfer Of Essential Fatty Acids By Marine Plankton, Adriana J. Veloza Jan 2005

Transfer Of Essential Fatty Acids By Marine Plankton, Adriana J. Veloza

Dissertations, Theses, and Masters Projects

Long chain n-3 polyunsaturated fatty acids (LCn-3 PUFAs) such as EPA and DHA are important biomolecules regulating production in marine ecosystems. This study examined how the interaction at the phytoplankton-zooplankton interface affected the transfer of LCn-3 PUFAs to higher trophic levels. Heterotrophic dinoflagellates contained higher levels of EPA and DHA than their algal prey, suggesting heterotrophic dinoflagellates enhanced the nutritional value of poor quality algae and subsequent transfer to the next trophic level. Formation of EPA and DHA in the dinoflagellates appears to be achieved by the elongation and desaturation of shorter fatty acid chains rather than through de novo ...


Investigation Of The Life History Of The Cownose Ray, Rhinoptera Bonasus (Mitchill 1815), Donna S. Grusha Jan 2005

Investigation Of The Life History Of The Cownose Ray, Rhinoptera Bonasus (Mitchill 1815), Donna S. Grusha

Dissertations, Theses, and Masters Projects

No abstract provided.


A Molecular Phylogeny Of The Echeneoidea (Perciformes: Carangoidei) And An Investigation Of Population Structuring Within The Echeneidae, Kurtis N. Gray Jan 2005

A Molecular Phylogeny Of The Echeneoidea (Perciformes: Carangoidei) And An Investigation Of Population Structuring Within The Echeneidae, Kurtis N. Gray

Dissertations, Theses, and Masters Projects

No abstract provided.


Nursery Delineation, Movement Patterns, And Migration Of The Sandbar Shark, Carcharhinus Plumbeus, In The Eastern Shore Of Virginia Coastal Bays And Lagoons, Christina L. Conrath Jan 2005

Nursery Delineation, Movement Patterns, And Migration Of The Sandbar Shark, Carcharhinus Plumbeus, In The Eastern Shore Of Virginia Coastal Bays And Lagoons, Christina L. Conrath

Dissertations, Theses, and Masters Projects

The identification and delineation of nursery areas and areas of aggregation of north Atlantic sharks has been identified as an important information need for future management efforts. The objectives of this project were to use a fishery-independent method to study the overwintering area of juvenile sandbar sharks, to spatially delineate the Eastern Shore nursery area, and to examine movement patterns and space use within this nursery area. Data from 21 satellite transmitters attached to large juvenile sandbar sharks revealed that these sharks primarily occurred off the outer banks of North Carolina, at deeper depths and colder water temperatures during the ...


Kinematics And Fluid Dynamics Of The Ventilatory Cycle In Carp (Cyprinus Carpio), William Todd Callan Jan 2005

Kinematics And Fluid Dynamics Of The Ventilatory Cycle In Carp (Cyprinus Carpio), William Todd Callan

Dissertations, Theses, and Masters Projects

No abstract provided.


Application Of Survival Analysis Methods To Pulsed Exposures: Exposure Duration, Latent Mortality, Recovery Time, And The Underlying Theory Of Survival Distribution Models, Yuan Zhao Jan 2005

Application Of Survival Analysis Methods To Pulsed Exposures: Exposure Duration, Latent Mortality, Recovery Time, And The Underlying Theory Of Survival Distribution Models, Yuan Zhao

Dissertations, Theses, and Masters Projects

Ecotoxicologists adopted median lethal concentration (LC50) methods from mammalian toxicology. This conventional LC50 approach has shortcomings. Fixing the exposure duration and selecting the 50% mortality level result in loss of ecologically relevant information generated at all other times. It also ignores latent mortality that can manifest after exposure ends. as a result, it cannot adequately predict pulsed exposure effects in which concentration, duration, and frequency of pulses change through time. The underlying theory of the dose-response models used to calculate LC50 values, stochastic versus individual effective dose (IED) theory, has not been tested rigorously either. In this study, the effects ...


Influence Of Environmental Factors On The Seed Ecology Of Vallisneria Americana, Jessie J. Campbell Jan 2005

Influence Of Environmental Factors On The Seed Ecology Of Vallisneria Americana, Jessie J. Campbell

Dissertations, Theses, and Masters Projects

Environmental conditions may positively or negatively influence production, reproduction, and restoration of submerged aquatic vegetation (SAV). As SAV populations decline, it is important to understand the potential impacts of the environment on the natural processes of reproduction. The objectives of this study are to provide fundamental information on sexual reproduction in a dominant species of freshwater SAV, Vallisneria americana, in the Chesapeake Bay observe the changes in environmental conditions in an established V. americana bed over an entire growing season (April-October), quantify the effects of similar environmental conditions on V. americana seed germination under controlled laboratory conditions, and finally to ...