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Full-Text Articles in Life Sciences

Fall 1999, Nsu Oceanographic Center Oct 1999

Fall 1999, Nsu Oceanographic Center

Currents

No abstract provided.


What Does It Take To Become A Marine Scientist?, Virginia Institute Of Marine Science Sep 1999

What Does It Take To Become A Marine Scientist?, Virginia Institute Of Marine Science

Reports

Note: This material may not meet current educational standards and is presented as part of the Institute's historical publications.


Summer 1999, Nsu Oceanographic Center Aug 1999

Summer 1999, Nsu Oceanographic Center

Currents

No abstract provided.


Fisheries Research Report No. 111 - Sea Temperature Variability Off Western Australia 1990 To 1994, Alan Pearce, Mark Rossbach, Marion Tait, Rhys Brown Jul 1999

Fisheries Research Report No. 111 - Sea Temperature Variability Off Western Australia 1990 To 1994, Alan Pearce, Mark Rossbach, Marion Tait, Rhys Brown

Fisheries research reports

Analysis of temperature data from coastal waters between Shark Bay and Cape Mentelle has shown the main features of temporal and spatial variability in temperature along the Western Australian coastline. Three distinct periods of variability emerge: the annual cycle (peak temperatures generally in January-February and troughs in July-August), a few-day (weatherrelated) cycle, and the diurnal pattern.

Summer temperatures range from 24° C (South Passage) to 19° C (Cape Mentelle), and winter temperatures from 21° C (South Passage) to 16° C (Marmion). Mean annual temperature ranges (winter minimum to summer maximum) are between 3° C (South Passage) and 7° C (Alkimos), …


Nitrate Reductase Activity, Nitrate Uptake And Iodine Speciation In The Marine Environment, Chin-Chang Hung Jul 1999

Nitrate Reductase Activity, Nitrate Uptake And Iodine Speciation In The Marine Environment, Chin-Chang Hung

OES Theses and Dissertations

The present method for the determination of new production (NP) by measuring the uptake of added 15NO3 suffers from a number of limitations. In an attempt to improve this situation, this research examined the possibility of estimating 15NO3– uptake by measuring the activity of nitrate reductase (NRA). In addition, because it has long been suspected that the biological reduction of IO3 to I may be mediated by nitrate reductase (NR), this research investigated the ability of NR to catalyze the reduction of iodate to iodide.

An improved method for the determination …


Spring 1999, Nsu Oceanographic Center Apr 1999

Spring 1999, Nsu Oceanographic Center

Currents

No abstract provided.


Production Of Copper-Complexing Ligands In Response To Elevated Concentrations Of Copper In Marine Synechococcus Spp., Arunsri Chatkaeomorakot Brown Apr 1999

Production Of Copper-Complexing Ligands In Response To Elevated Concentrations Of Copper In Marine Synechococcus Spp., Arunsri Chatkaeomorakot Brown

Theses and Dissertations in Biomedical Sciences

Synechococcus spp. (marine cyanobacteria) are extremely sensitive to copper toxicity and can produce high-affinity ligands of unknown structure which form complexes with free cupric ion. These ligands may contribute to the biological control of the levels of free cupric ions in surface seawater. Synechococcus spp. are known to produce metallothioneins (MT) in response to cadmium and zinc stress. In the present study the hypothesis that marine Synechococcus produce MT in response to copper was tested. Three marine Synechococcus spp. i.e., PCC 7001, PCC 73109, and PCC 7003, were exposed to different concentrations of CUSO 4 for various time periods. Size …


Benthic Community Analysis Of Hog Island Bay, Virginia, David James Lewis Apr 1999

Benthic Community Analysis Of Hog Island Bay, Virginia, David James Lewis

Biological Sciences Theses & Dissertations

The benthic infaunal macroinvertebrate communities of Hog Island Bay of the Virginia Eastern Shore were quantitatively sampled at 30 locations on August 31 and September 1, 1995. The primary objectives of this study were: (1) to characterize the subtidal macroinfaunal benthic communities of Hog Island Bay, (2) to examine relationships between abiotic factors and the macroinfaunal communities and (3) to characterize the environmental condition of the system using the Benthic Index of Biotic Integrity (B-IBI) (Weisburg et al. 1997) and the EMAP Benthic Index for the Virginian Province (Strobel et al. 1995).

The ecological condition of Hog Island Bay appears …


Winter 1999, Nsu Oceanographic Center Jan 1999

Winter 1999, Nsu Oceanographic Center

Currents

No abstract provided.


Infectious Necrotizing Enteritis And Mortality Caused By Vibrio Carachariae In Summer Flounder Paralichthys Dentatus During Intensive Culture, Bruno Soffientino, Todd Gwaltney, David R. Nelson, Jennifer L. Specker, Michael Mauel, Marta Gomez-Chiarri Jan 1999

Infectious Necrotizing Enteritis And Mortality Caused By Vibrio Carachariae In Summer Flounder Paralichthys Dentatus During Intensive Culture, Bruno Soffientino, Todd Gwaltney, David R. Nelson, Jennifer L. Specker, Michael Mauel, Marta Gomez-Chiarri

Fisheries, Animal and Veterinary Sciences Faculty Publications

An epizootic causing mortality among cultured summer flounder Paralichthys dentatus occurred in summer of 1998 at a land-based facility on Narragansett Bay, Rhode Island, USA. The disease, flounder infectious necrotizing enteritis (FINE), was characterized by reddening around the anal area, distended abdomens filled with opaque serosanguineous fluid, enteritis and necrosis of the posterior intestine. In extreme cases of the disease, the posterior intestine was detached from the anus and was observed coming out the vent. The intestine of individuals that recovered from the dsease ended in a blind-sac; the abdomens of these fish were distended, due to food and water …


Phytoplankton Growth Rates In The Ross Sea, Antarctica, Determined By Independent Methods: Temporal Variations, Walker O. Smith Jr., D. M. Nelson, S. Mathot Jan 1999

Phytoplankton Growth Rates In The Ross Sea, Antarctica, Determined By Independent Methods: Temporal Variations, Walker O. Smith Jr., D. M. Nelson, S. Mathot

VIMS Articles

The development of the seasonal phytoplankton bloom in the Ross Sea was studied during two cruises. The first, conducted in November-December 1994, investigated the initiation and rapid growth of the bloom, whereas the second (December 1995-January 1996) concentrated on the bloom's maximum biomass period and the subsequent decline in biomass. Central to the understanding of the controls of growth and the summer decline of the bloom is a quantitative assessment of the growth rate of phytoplankton. Growth rates were estimated over two time scales with different methods. The first estimated daily growth rates from isotopic incorporation under simulated in situ …


Habitat Fragmentation In Transplanted Eelgrass (Zostera Marina) Beds: Effects On Decapods And Fish, Alfonso Vollmer Lombana Jan 1999

Habitat Fragmentation In Transplanted Eelgrass (Zostera Marina) Beds: Effects On Decapods And Fish, Alfonso Vollmer Lombana

Dissertations, Theses, and Masters Projects

No abstract provided.


The Cause And Consequence Of Ontogenetic Changes In Social Aggregation In New Zealand Spiny Lobsters, Mark J. Butler Iv, Alistair B. Macdiarmid, John D. Booth Jan 1999

The Cause And Consequence Of Ontogenetic Changes In Social Aggregation In New Zealand Spiny Lobsters, Mark J. Butler Iv, Alistair B. Macdiarmid, John D. Booth

Biological Sciences Faculty Publications

Ontogenetic changes in the behavior, spatial distribution, or habitat use of a species are presumably adaptations to ecological forces that differ in their effect on various life stages. The New Zealand rock lobster Jasus edwardsii is one of several species of spiny lobster that exhibits dramatic ontogenetic shifts in sociality and spatial distribution, and we tested whether such changes are adaptive. We first surveyed several natural populations of J. edwardsii to document size-specific differences in aggregation. To determine if chemical cues discharged by conspecifics promote aggregation of certain ontogenetic stages, we tested the responsiveness of lobsters of 3 ontogenetic stages …


Modeling The Effects Of Doliolids On The Plankton Community Structure Of The Southeastern Us Continental Shelf, A. G. Edward Haskell, Eileen E. Hofmann, Gustav-Adolf Paffenhofer, Peter G. Verity Jan 1999

Modeling The Effects Of Doliolids On The Plankton Community Structure Of The Southeastern Us Continental Shelf, A. G. Edward Haskell, Eileen E. Hofmann, Gustav-Adolf Paffenhofer, Peter G. Verity

CCPO Publications

A model of the lower trophic levels that consists of a system of coupled ordinary differential equations was developed to investigate the time-dependent behavior of doliolid populations associated with upwelling features on the outer southeastern US continental shelf. Model equations describe the interactions of doliolids with two phytoplankton size fractions, five copepod developmental stages and a detrital pool. Additional equations describe nitrate and ammonia. Model dynamics are based primarily upon data obtained from field and laboratory experiments for southeastern US continental shelf plankton populations. Variations on a reference simulation, which represents average upwelling conditions without doliolids, were carried out to …


Limitation Of Algal Growth By Iron Deficiency In The Australian Subantarctic Region, Peter N. Sedwick, Giacomo R. Ditullio, David A. Hutchins, Philip W. Boyd, F. Brian Griffiths, A. Clive Crossley, Thomas W. Trull, Bernard Queguiner Jan 1999

Limitation Of Algal Growth By Iron Deficiency In The Australian Subantarctic Region, Peter N. Sedwick, Giacomo R. Ditullio, David A. Hutchins, Philip W. Boyd, F. Brian Griffiths, A. Clive Crossley, Thomas W. Trull, Bernard Queguiner

OES Faculty Publications

In March 1998 we measured iron in the upper water column and conducted iron- and nutrient-enrichment bottle-incubation experiments in the open-ocean Subantarctic region southwest of Tasmania, Australia. In the Subtropical Convergence Zone (∼42°S, 142°E), silicic acid concentrations were low (< 1.5μM) in the upper water column, whereas pronounced vertical gradients in dissolved iron concentration (0.12-0.84 nM) were observed., presumably reflecting the interleaving of Subtropical and Subantarctic waters, and mineral aerosol input. Results of a bottle-incubation experiment performed at this location indicate that phytoplankton growth rates were limited by iron deficiency within the iron-poor layer of the euphotic zone. In the Subantarctic water mass (∼46.8°S, 142°E), low concentrations of dissolved iron (0.05-0.11nM) and silicic acid (< 1μM) were measured throughout the upper water column, and our experimental results indicate that algal growth was limited by iron deficiency. These observations suggest that availability of dissolved iron is a primary factor limiting phytoplankton growth over much of the Subantarctic Southern Ocean in the late summer and autumn.


Sensory Development In Settlement-Stage Larvae Of Caribbean Labrids And Scarids: A Comparative Study With Implications For Ecomorphology And Life History Strategies, Monica R. Lara Jan 1999

Sensory Development In Settlement-Stage Larvae Of Caribbean Labrids And Scarids: A Comparative Study With Implications For Ecomorphology And Life History Strategies, Monica R. Lara

Dissertations, Theses, and Masters Projects

The sensory capabilities of settlement-stage fishes are unknown but this information is necessary to studies of larval settlement and recruitment. The morphology of the cephalic lateral line, eye and external olfactory organ of thirteen species of settlement-stage Caribbean labroids was described. Scanning electron images of the cephalic lateral line neuromasts, lateral line canals and olfactory epithelia and histological studies of the retinae and morphological measurements of visual acuity were used to assess the level of sensory development attained at settlement. The sensory capabilities of settlement-stage fishes are discussed in relation to the possible cues settlement-stage fishes may be using to …


A Comparison Of Size Selectivity And Relative Efficiency Of Sea Scallop Trawls And Dredges, David B. Rudders Jan 1999

A Comparison Of Size Selectivity And Relative Efficiency Of Sea Scallop Trawls And Dredges, David B. Rudders

Dissertations, Theses, and Masters Projects

No abstract provided.


Resource Allocation And Sucrose Mobilization In Light Limited Eelgrass Zostera Marina, Teresa Alcoverro, Richard C. Zimmerman, Donald G. Kohrs, Randall S. Alberte Jan 1999

Resource Allocation And Sucrose Mobilization In Light Limited Eelgrass Zostera Marina, Teresa Alcoverro, Richard C. Zimmerman, Donald G. Kohrs, Randall S. Alberte

OES Faculty Publications

This study evaluated the ability of Zostera marina L. (eelgrass) to balance the daily photosynthetic deficit by mobilization of carbon reserves stored in below-ground tissues during a period of extreme winter light limitation. A quantitative understanding of the mobilization process and its limitations is essential to the development of robust models predicting minimum light levels required to maintain healthy seagrass populations. Plants were grown in running seawater tanks under 2 light regimes. One treatment was provided with 2 h irradiance-saturated photosynthesis (Hsat) to produce severe Light Limitation, while control plants were grown under 7 h Hsat, …


Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter Jan 1999

Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter

Dissertations, Theses, and Masters Projects

No abstract provided.


Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman Jan 1999

Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman

Dissertations, Theses, and Masters Projects

No abstract provided.


Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church Jan 1999

Limitation Of Bacterial Growth By Dissolved Organic Matter And Iron In The Southern Ocean, Matthew J. Church

Dissertations, Theses, and Masters Projects

No abstract provided.


Functional And Molecular Analysis Of Antibody Affinity Maturation In Rainbow Trout (Oncorhynchus Mykiss), Haili Zhang Jan 1999

Functional And Molecular Analysis Of Antibody Affinity Maturation In Rainbow Trout (Oncorhynchus Mykiss), Haili Zhang

Dissertations, Theses, and Masters Projects

No abstract provided.


The Impacts Of External Nutrient Sources On Marine Phytoplankton In An Eastern Shore Sea-Side Estuary, Claudette Lajoie Jenkins Jan 1999

The Impacts Of External Nutrient Sources On Marine Phytoplankton In An Eastern Shore Sea-Side Estuary, Claudette Lajoie Jenkins

OES Theses and Dissertations

The Eastern Shore of Virginia (Greens Creek) as well as a large portion of the North Atlantic coastline is characterized by estuarine systems not dominated by large river systems. Instead, small freshwater creeks influence many coastal systems yet little information has been documented on their ecological significance. The focus of this research is to identify the biogeochemical and physical interactions within an estuarine water-column and understand the importance of freshwater sources in governing phytoplankton production. The hypothesis of this research is that increases in external nutrient loading into Greens Creek will not result in an increase in primary production. The …


Spatial And Temporal Distributions Of Organic Matter And Polycyclic Aromatic Hydrocarbons (Pahs) In Surface Waters Of The York River, Va Estuary, Rebecca E. Countway Jan 1999

Spatial And Temporal Distributions Of Organic Matter And Polycyclic Aromatic Hydrocarbons (Pahs) In Surface Waters Of The York River, Va Estuary, Rebecca E. Countway

Dissertations, Theses, and Masters Projects

No abstract provided.


Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway Jan 1999

Carbon Production And Growth Physiology Of Heterotrophic Bacteria In A Subtropical Coral Reef Ecosystem, Peter Dylan Countway

Dissertations, Theses, and Masters Projects

No abstract provided.


Comparative Study Of Selenium Requirements Of Three Phytoplankton Species: Gymnodinium Catenatum, Alexandrium Minutum (Dinophyta) And Chaetoceros Cf. Tenuissimus (Bacillariophyta, Martina A. Doblin, Susan I. Blackburn, Gustaaf M. Hallegraeff Jan 1999

Comparative Study Of Selenium Requirements Of Three Phytoplankton Species: Gymnodinium Catenatum, Alexandrium Minutum (Dinophyta) And Chaetoceros Cf. Tenuissimus (Bacillariophyta, Martina A. Doblin, Susan I. Blackburn, Gustaaf M. Hallegraeff

OES Faculty Publications

This study investigated the selenium (Se) requirements of three phytoplankton species which commonly bloom in southern Australian estuaries. The present study showed that the toxic dinoflagellate Gymnodinium catenatum Graham had an obligate requirement for Se (IV) in culture. After two transfers (~ 4 weeks ≈ 7 generations) in Se-deficient seawater medium, this phytoplankton species exhibited a decline in growth rate (25%) and biomass yield (90%), while complete cessation of cell division occurred under prolonged (8 weeks ≈ 12 generations) Se starvation. Addition of 10-9-10-7 M H2SeO3 to nutrient-enriched seawater medium resulted in increased G.catenatum …