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Articles 1 - 13 of 13
Full-Text Articles in Marine Biology
The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba
The Role Of Copepods And Heterotrophic Dinoflagellates In The Production Of Dissolved Organic Matter And Inorganic Nutrients, Grace Kathleen Saba
Dissertations, Theses, and Masters Projects
Zooplankton play a key role in the cycling of dissolved organic matter (DOM) and inorganic nutrients. The factors that affect these processes, however, are not fully understood. I measured the effects of various diets on DOM and inorganic nutrient production by the copepod Acartia tonsa and the heterotrophic dinoflagellate Oxyrrhis marina, and explored the mechanisms of nutrient release from copepods. Copepods feeding on a mixed diet, the preferred diet of most copepods, had significantly lower dissolved organic carbon (DOC), ammonium (NH4+), and total dissolved nitrogen (TDN) release rates compared to feeding on a carnivorous or herbivorous diet. Thus, copepod feeding …
Assessing Genetic Variation Within And Among Native Populations And Hatchery Stocks Of Crassostrea Ariakensis Using Microsatellite Markers, Jie Xiao
Dissertations, Theses, and Masters Projects
Assessing genetic variation within and among native populations and hatchery stocks of Crassostrea ariakensis using microsatellite markers In response to the dramatic decline of eastern oyster (Crassostrea virginica) populations in the Chesapeake Bay, introduction of the non-native Asian oyster Crassostrea ariakensis has been proposed. Currently several hatchery stocks of C. ariakensis, derived from a few wild populations along the coast of Japan and China, are being maintained in U.S. hatcheries in the Pacific northwest and on the east coast. In recent years, as the risks of the proposed introduction are being assessed, these hatchery animals have been widely used for …
Stable Isotope Dynamics In Summer Flounder Tissues, With Application To Dietary Assessments In Chesapeake Bay, Andre Buchheister
Stable Isotope Dynamics In Summer Flounder Tissues, With Application To Dietary Assessments In Chesapeake Bay, Andre Buchheister
Dissertations, Theses, and Masters Projects
Stable isotope techniques were applied to summer flounder, Paralichthys dentatus, in Chesapeake Bay to elucidate the relative importance of different prey groups on the growth and productivity of this species. Prior to field application, a laboratory diet-shift study was conducted to evaluate methodological assumptions and obtain necessary isotopic parameters. Specifically, the goals of the laboratory study were to 1) determine isotopic turnover rates and fractionations of δ13C and δ15N in liver, whole blood, and white muscle and 2) estimate the relative importance of growth and metabolic processes on isotopic turnover. Groups of captive juvenile summer flounder (130-255mm total length) were …
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
A Molecular Technique For Specific Identification Of Western Atlantic Ocean Scombrids And An Analysis Of A Larval Scombrid Assemblage Off The Kona Coast Of Hawaii, Melissa A. Paine
Dissertations, Theses, and Masters Projects
No abstract provided.
Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown
Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown
Dissertations, Theses, and Masters Projects
Perkinsus marinus is the causative agent of the oyster disease Dermo in the eastern oyster, Crassostrea virginica. In vitro propagation of the parasite has led to the establishment of multiple isolates by several investigators. Little work, however, has been done to characterize different isolates. In this study multiple isolates were examined for genetic and biochemical diversity. at two loci, the ITS region and the ATAN region, there was as much intra-isolate genetic variation among DNA sequences of some isolates as there was inter-isolate variation. Variation was also observed at a third loci, a subtilisin-like serine protease gene. This is the …
Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr
Environmental Stress In Hard Coral: Evaluating Lipid As An Indicator Of Sublethal Stress On Short Time Scales, David Harold Niebuhr
Dissertations, Theses, and Masters Projects
Lipid quality was evaluated in Montastrea spp. under sediment- and heat-stressed conditions to evaluate lipid ratio as an indicator of sub-lethal stress on short time scales. The ratio of storage lipid (wax ester + triacylglyceride) to structural lipid (sterol esters + phospholipid) decreased significantly (0.25 to 0.14, p < 0.01) after experimental sedimentation. FAME analysis of colonies exposed to experimental sedimentation showed a reduction of the algal, 18:3(n-6) and 18:4(n-3), polyunsaturated fatty acid (PUFA) in the polar lipid fraction. This loss of PUFA suggests a loss of algal membrane in sediment-stressed colonies. Lipid quality was similarly measured in M. faveolata over a 10-day period. Mean (n = 20) ratio of storage to structural lipid in M. faveolata dropped from 2.43 to a level of 0.98 immediately following a natural sedimentation event before recovering to levels of 1.4 and 2.9 on post-storm days 2 and 4, respectively. Colonies of M. annularis subject to heat-stress (35??C) exhibited no significant change in storage lipid ratio, while levels of Free Fatty Acids increased significantly from 0.012 (n = 22) to 0.156 mg lipid/g dry tissue (n = 22)(p < 0.05). FAME analysis of tissue lipids extracted from the heat-stressed colonies showed changes in the polar fraction, with significant decreases in the 18:3(n-6), 18:3(n-3), 18:4(n-3), 20:4(n-6) and 20:5(n-3) (p < 0.05) PUFA and subsequent significant increases in the saturated fatty acids, 16:0 and 18:0 (p < 0.05). These changes in lipid quantity and quality indicate possible oxidation and preferential digestion of zooxanthellar membranes. Stress experiments were repeated in M. annularis using VacutainerRTM blood collection tubes to collect micro-tissue samples without destroying skeleton of the sample colonies. A significant decrease in storage: structural lipid ratio after sedimentation was also detected using the micro-tissue technique. This study indicates that the relative abundance of lipid subclass components can indicate sub-lethal environmental stress, on short time scales, in M. annularis and M. faveolata. Furthermore, micro-tissue collection techniques permit repeated monitoring coral colonies to assess the manifestation of stress from first detection of impact at the cellular level to changes in community to changes in community structure detectable over longer time scales.
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Dissertations, Theses, and Masters Projects
No abstract provided.
Ground Breaking Ceremony For The Marine Chemistry & Toxicology Building, Virginia Institute Of Marine Science, School Of Marine Science, College Of William And Mary
Ground Breaking Ceremony For The Marine Chemistry & Toxicology Building, Virginia Institute Of Marine Science, School Of Marine Science, College Of William And Mary
Miscellaneous
Ceremony held April 13, 1995. Program of the event.
Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik
Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik
Dissertations, Theses, and Masters Projects
There has been a growing interest in the commercial aquaculture of striped bass, Morone saxatilis. Little is known, however, about the nutritional requirements and feeding physiology of striped bass larvae. The objectives of this study were (a) to evaluate the efficiency of the live food enrichment techniques in studying the nutritional requirements for polyunsaturated fatty acids (PUFA), phospholipids and free amino acids, (b) to determine the ontogenetic changes of lipolytic enzymes, and (c) to develop a microencapsulated diet for striped bass larvae as full or partial replacement of live food. Three enrichment techniques, namely, microencapsulated fish oil, yeast/fish oil emulsion …
The Presence Of Acid Polysaccharides In The Mesogloea Of Chrysaora Quinquecirrha, Edward P. Gardner
The Presence Of Acid Polysaccharides In The Mesogloea Of Chrysaora Quinquecirrha, Edward P. Gardner
Dissertations, Theses, and Masters Projects
No abstract provided.
Variations In Major Cations And Certain Heavy Metals In The Serum Of The Blue Crab, Callinectes Sapidus, James Alden Colvocoresses
Variations In Major Cations And Certain Heavy Metals In The Serum Of The Blue Crab, Callinectes Sapidus, James Alden Colvocoresses
Dissertations, Theses, and Masters Projects
No abstract provided.
The Effects Of Environmental Salinity On Free Amino Acids Of Crassostrea Virginica, Maurice Patrick Lynch
The Effects Of Environmental Salinity On Free Amino Acids Of Crassostrea Virginica, Maurice Patrick Lynch
Dissertations, Theses, and Masters Projects
No abstract provided.
Effect Of Environmental Salinity On The Amino Acids Of Balanus Improvisus Darwin, Joan L. Faunce
Effect Of Environmental Salinity On The Amino Acids Of Balanus Improvisus Darwin, Joan L. Faunce
Dissertations, Theses, and Masters Projects
No abstract provided.