Oceanography Commons^™

Biophysical Interactions In The Straits Of Florida: Turbulent Mixing Due To Diel Vertical Migrations Of Zooplankton, Cayla Whitney Dean

HCNSO Student Theses and Dissertations

Diel vertical migrations (DVM) comprise the largest animal migration on the planet and are a phenomenon present in all bodies of water on Earth. A strong sound scattering layer undergoing DVM was observed in the Straits of Florida via a bottom-mounted Acoustic Doppler current profiler (ADCP) Workhorse Longranger 75 kHz (Teledyne RD Instruments) located at the 244 m isobath. ADCP average backscatter showed a clear periodicity corresponding with sunrise and sunset times indicating the presence of a nocturnal DVM. Analysis of the ADCP backscatter data indicated zooplankton swimming velocities were faster during sunrise than sunset times. In several cases the …

Organic Copper Binding Ligands And Thiol Compounds Produced By Bacteria And In The Elizabeth River, Virginia, Christina Louise Dryden

OES Theses and Dissertations

This dissertation presents work focusing on copper and organic copper binding ligands in laboratory cultures and the Elizabeth River, Virginia. Laboratory cultures of the marine bacterium Vibrio parahaemolyticus were used to demonstrate the influence of elevated copper concentrations on copper-complexing ligand and thiol production. Copper-complexing ligands similar in binding strength to the strongest natural ligands were detected in V. parahaemolyticus cultures (log K′_CuL = 11.8–13.2). A strong correlation (r² = 0.973) was found between total thiol and copper-complexing ligand concentrations at all copper concentrations examined.

A yearlong seasonal study was undertaken in a heavily polluted estuary to ascertain …

A Comprehensive Evaluation Of C25 Highly Branched Isoprenoid Alkenes Of Marine Diatoms As Proxies For Sea Ice Extent In The Arctic Ocean, Tetiana Muniak

OES Theses and Dissertations

Sea Ice extent is one of the major factors regulating carbon cycling and ecosystem function in the modern Arctic Ocean. It is an essential component of climate models and is crucial for the evaluation of various oceanographic processes that influence a particular region. Yet it is also one of the most difficult attributes of the ocean with respect to our ability for its accurate reconstruction from paleo records. The lack of the detailed records prior to satellite information has encouraged the development of new proxy records for the reconstruction of past

sea ice conditions. In recent years, a new monounsaturated …

Spatial And Temporal Variability In Net Community Metabolism In The Middle Atlantic Bight, Georges Bank, And Gulf Of Maine: Observations Of Net Heterotrophic Phases In The Highly Productive Coastal Zone, Cory James Staryk

OES Theses and Dissertations

Net community metabolism (NCM), the balance between primary production and community respiration, was measured during two cruises, June 2011 and August 2012, in the Middle Atlantic Bight, Georges Bank and Gulf of Maine. Net heterotrophy was observed in Georges Bank and Gulf of Maine during the June 2011 cruise. During the August 2012 cruise, net heterotrophy was observed in the Middle Atlantic Bight and net autotrophy was observed in Georges Bank and the Gulf of Maine. Dark community respiration increased (DCR) with biomass and temperature. Gross community production (GCP) also increased with Chl a, bicarbonate uptake, and temperature. Net …

The Saco River Plume: A Discussion Of The Near-Field Dynamics, Barbara A. Fortier

All Theses And Dissertations

This study focused on the freshwater discharge plume from the Saco River in southwestern Maine to determine the mechanisms responsible for the largest impacts on the near-field dynamics in this region. We examined the forcing factors that tended to increase the plume's spatial extent upshelf of the river mouth. Salinity, temperature, and density data were collected during cruises from May through November 2010 and by two surface moorings deployed upshelf of the Saco River mouth. We found a distinct variation in the latitude of the upshelf boundary of the plume during and after periods of high discharge. Furthermore, we found …

Implications Of Climate Change For Cyanobacteria Over The Western Florida Shelf In The Gulf Of Mexico, Ivy Mara Ozmon

OES Theses and Dissertations

Concentrations of atmospheric CO₂ are expected to double by year 2100 as a result of anthropogenic activities. Under elevated CO₂ conditions, cyanobacteria may reallocate energy from active accumulation and transport of dissolved inorganic carbon (C) required for photosynthesis to other growth processes. Stimulation of cyanobacterial production on the Western Florida Shelf in the Gulf of Mexico (GOM) could lead to improved nutritional status for the toxic, mixotrophic dinoflagellate Karenia brevis that utilizes newly fixed N₂ from co-occurring diazotrophic cyanobacteria and consumes unicellular cyanobacteria via grazing for growth. Culture studies performed by other researchers on the climate induced …

Multiplatform, Multidisciplinary Investigations Of The Impacts Of Modified Circumpolar Deep Water In The Ross Sea, Antarctica, Walker O. Smith, Kimberly T. Goetz, Daniel E. Kaufman, Bastien Y. Queste, Vernon Asper, Daniel P. Costa, Michael S. Dinniman, Marjorie A. M. Friedrichs, Eileen E. Hofmann, Karen J. Heywood, John M. Klinck, Josh T. Kohut, Craig M. Lee

CCPO Publications

In 2010–2011, three projects combined to characterize the temporal and spatial distributions of Modified Circumpolar Deep Water (MCDW) in the Ross Sea using icebreaker-based sampling, gliders, instrumented seals, and hindcasts from a numerical circulation model. Te fieldwork clearly identified MCDW throughout the Ross Sea, and the data were used to determine its influence on potential heat and nutrient inputs and biotic distributions. Furthermore, the numerical simulations confirm its apparent trajectory and location. Substantial small-scale variability in oceanographic and biological distributions suggests that such variability may play an important role in biogeochemical cycles. Data from the three projects provide a view …

Exploring The Link Between Otolith Growth And Function Along The Biological Continuum In The Context Of Ocean Acidification, Eric D. Wilcox Freeburg

Graduate Doctoral Dissertations

Oceans are acidifying as atmospheric CO₂ is drawn down. This process, known as ocean acidification (OA), is well known and documented. Over the next 100 years, pH of the surface ocean is projected to decrease by up to 0.35 units. This CO₂ draw down has a direct effect on dissolved inorganic carbon (DIC) balance in the ocean. OA is expected to impact calcifying organisms that rely on constituencies of the DIC system, specifically carbonate ion [CO₃2-]. It is clear that externally calcified structures, such as coral skeletons, bivalve shells, etc., will be significantly affected as pH, …

The Relocation Of Laurel Hill Plantation Rice Barges In The Waccamaw River, Sc, Using Multibeam Echosounding, Nathalie Arnone

Honors Theses

A study done in the lower Waccamaw River neck, inland of Murrells Inlet, South Carolina, is done to relocate and bathymetrically map antebellum rice barge wrecks, last seen near the old Laurel Hill Plantation area. Sites investigated are Laurel Hill, Collins Creek, Cow House Creek, and the Wachesaw portion of the Waccamaw River. Magnetometer data contained multiple anomalies along the locations, mostly due to modern wrecks. Successful multibeam echosounding performed at the Laurel Hill site reveals two identifiable barges. Following archeological scuba diving provided that one barge was partially buried and upside-down, containing civil war era metal fastenings. Barges found …

Exploration Of Biophysical Interactions Associated With Mesoscale Variability In The Central Gulf Of Mexico, Katharine Celeste Woodard

Master's Theses

Bio-physical coupling in the Gulf of Mexico (GMx) is explored in this research using an integrated satellite sensor approach. Physical features are identified using Sea Level Anomaly (SLa) produced by Archiving, Validation, and Interpretation of Satellite Oceanographic data (AVISO). Biological characteristics of the GMx have been recognized as ocean color identified by the satellites SeaWiFS and MODISA. A climatology data set and a chlorophyll anomaly (CLa) was made using the 14-year mean determined from the ocean color files. The hypotheses are that there will be an inverse relationship between SLa and CLa, that mesoscale SLa features will significantly modulate local …

A Collaborative International Research Program On The Coupled North Atlantic-Arctic System: Science Plan, Eileen E. Hoffmann, Mike St. John, Heather M. Benway

CCPO Publications

This North Atlantic-Arctic science plan is derived from an international workshop held in April 2014 with support from the National Science Foundation Division of Ocean Sciences and the European Union (EU). The workshop was designed to facilitate development of a core vision for advancing the next phase of research on the North Atlantic-Arctic system and strengthening international collaborations within and between the EU and North America.

Resisting The Canon: Maori And The New Zealand Short Story Canon 1953-1984, Rachel Lacasse-Ford

Open Access Theses

This thesis offers informed readings of a wide selection of short stories by both Pakeha (ethnically European New Zealand) and Maori (indigenous peoples of Aotearoa New Zealand) writers in an effort to place these stories, and anthologies in which they are canonized, within a cultural and historical context. It provides a concise literary genealogy of the Maori within the New Zealand short story, and it explores the ways Maori short story writers pushed back against racist portrayals of Maori and efforts to silence or contain the Maori voice.

Comparison Of Two Separation Methods For Biological Particles: Field-Flow Fractionation (Fff) And Sucrose Density Gradients, Cody E. Garrison

OES Theses and Dissertations

Sucrose gradient centrifugation and Field-flow fractionation (FFF) are two different particle separation methods that overcome the problems of similar size microorganisms clumping together during standard filtration methods. FFF separates particles based on size and density via the parabolic velocity profile of laminar flow in a ribbon-like channel. The sucrose method separates particles via centrifugation in a density gradient. Both techniques worked well in separating eukaryotic from prokaryotic microbes, with the preferred method depending on the type and relative abundance of organisms to be separated. Minicells were separated from mother cells in transformed Escherichia coli cultures, heterotrophic flagellates (e.g., Diplonema papillatum …

Quantifying The Impact Of Atmospheric Deposition On The Biogeochemistry Of Fe And Al In The Upper Ocean: A Decade Of Collaboration With The Us Clivar-Co2 Repeat Hydrography Program, Maxime Grand, Clifton Buck, William Landing, Christopher Measures, Mariko Hatta, William Hiscock, Matthew Brown, Joseph Resing

Faculty Publications

The aerosol deposition of continental material and its partial dissolution in the surface ocean exerts an important control on the distribution of iron and other potentially limiting trace metal (TM) micronutrients in the open ocean. This dust deposition has implications for the regulation of global climate through the coupling of biolimiting TM cycles, marine productivity, and the global carbon cycle. Thus, it is important to determine the locations of dust deposition in the open ocean and to quantify the magnitude and subsequent dissolution of the dust. At present, there are too few dust deposition estimates and solubility measurements in the …

Kenyan Climate Variation Assessment Through Rainfall Anomalies And Sea Surface Temperature (Sst) Correlations, Kimberly E. Lykens

STAR Program Research Presentations

The diverse and varied climate of Eastern Africa’s Kenya is home to an agriculturally dependent populace, in which farmers and other related economic sectors make up the majority of livelihoods and gross domestic product. Recurring droughts and severe flooding are major concerns for local farmers and governmental entities. The purpose of this study is to identify and categorize differences in rainfall trends over Kenya and to examine relationships between seasonal rainfall anomalies of sea surface temperature (SST), with an ultimate goal to improve predictions of wet season rainfall amounts. The analysis began with data from 27 national and cooperative weather …

Degradable Plastics And Their Potential To Affect Solid Waste Systems, Krista L. Thyberg, David J. Tonjes

Technology & Society Faculty Publications

Plastic waste forms a substantial part of municipal solid waste and has caused environmental concerns, particularly due to chemical contamination of the environment and effects from persistent litter. Plastics also complicate waste management processes, such as by having poor recovery rates through recycling, and causing contamination in composting operations. One potential means to address some of these challenges is through degradable plastics which, unlike conventional plastics, are designed to decompose at an accelerated rate in specific environments. Degradable plastics aim to address the end-of-life of plastic products and are intended to reduce the environmental impacts associated with their use and …

Fall 2014, Nsu Oceanographic Center

Currents

No abstract provided.

Spring 2014, Nsu Oceanographic Center

Currents

No abstract provided.

Reproduction And Population Of Porites Divaricata At Rodriguez Key: The Florida Keys, Usa, John Mcdermond

HCNSO Student Theses and Dissertations

Sexual reproduction in Porites divaricata (Le Sueur, 1820) was studied over a one year period (August, 2012 to August, 2013) in a shallow water (~2m depth) carbonate bank (also described as marginal) habitat at Rodriguez Key, a small island located 1.44 km off the east coast of Key Largo. Porites divaricata is a brooding, gonochoric species with peak reproductive output (planula release) occurring in March and at least a smaller event in May. This species showed an overall female to male sex ratio of 3.5:1. However, during peak reproduction, the sex ratio was 1.2:1. Spawning (sperm release) most likely occurred …

Weekly Gridded Aquarius L-Band Radiometer/Scatterometer Observations And Salinity Retrievals Over The Polar Regions - Part 1: Product Description, L. Brucker, Emmanuel P. Dinnat, L. S. Koenig

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Passive and active observations at L band (frequency similar to 1.4 GHz) from the Aquarius/SAC-D mission offer new capabilities to study the polar regions. Due to the lack of polar-gridded products, however, applications over the cryosphere have been limited. We present three weekly polar-gridded products of Aquarius data to improve our understanding of L-band observations of ice sheets, sea ice, permafrost, and the polar oceans. Additionally, these products intend to facilitate access to L-band data, and can be used to assist in algorithm developments. Aquarius data at latitudes higher than 50 degrees are averaged and gridded into weekly products of …

Weekly Gridded Aquarius L-Band Radiometer/Scatterometer Observations And Salinity Retrievals Over The Polar Regions - Part 2: Initial Product Analysis, L. Brucker, Emmanuel P. Dinnat, L. S. Koenig

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Following the development and availability of Aquarius weekly polar-gridded products, this study presents the spatial and temporal radiometer and scatterometer observations at L band (frequency similar to 1.4 GHz) over the cryosphere including the Greenland and Antarctic ice sheets, sea ice in both hemispheres, and over sub-Arctic land for monitoring the soil freeze/thaw state. We provide multiple examples of scientific applications for the L-band data over the cryosphere. For example, we show that over the Greenland Ice Sheet, the unusual 2012 melt event lead to an L-band brightness temperature (TB) sustained decrease of similar to 5K at horizontal polarization. Over …

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …

Molecular Characterization And Photochemical Transformation Of Dissolved Organic Matter From Land To Ocean, Hongmei Chen

Chemistry & Biochemistry Theses & Dissertations

Molecular characterization and photochemical transformation of dissolved organic matter (DOM) in both rivers and the ocean is the main research focus of this dissertation. Chemical characterization of DOM is hampered by the limited application of advanced techniques to desalt, concentrate, isolate and then molecularly characterize DOM. An affordable, commercially available mini-electrodialysis (mini-ED) system has been evaluated and recommended for the efficient desalting of small volume samples of seawater prior to analysis by electrospray Fourier transform ion cyclotron resonance mass spectrometry (ESI FTICR-MS).

A high-recovery technique of DOM isolation – reverse osmosis coupled with electrodialysis (RO/ED) – was used to isolate …

Phytoplankton And Nutrient Dynamics In A Tidally Dominated Eutrophic Estuary: Daily Variability And Controls On Bloom Formation, Ryan E. Morse, Margaret R. Mulholland, Todd A. Egerton, Harold G. Marshall

OES Faculty Publications

To better understand nutrient dynamics and factors that promote the initiation of algal blooms, the Lafayette River, a tidal subestuary of Chesapeake Bay that experiences seasonal algal blooms, was sampled daily for a period of 54 d in the fall of 2005. Three phytoplankton blooms (chl a concentrations exceeding twice the average of monthly measurements from 2000 to 2009) occurred during this period: a mixed bloom of Akashiwo sanguinea and Gymnodinium sp., a monospecific Skeletonema costatum bloom, and a monospecific Gymnodinium sp. bloom. Over the sampling period, nutrient concentrations increased following precipitation events and were elevated between bloom periods but …

The Great 2012 Arctic Ocean Summer Cyclone Enhanced Biological Productivity On The Shelves, Jinlun Zhang, Carin Ashjian, Robert Campbell, Victoria Hill, Yvette H. Spitz, Michael Steele

OES Faculty Publications

A coupled biophysical model is used to examine the impact of the great Arctic cyclone of early August 2012 on the marine planktonic ecosystem in the Pacific sector of the Arctic Ocean (PSA). Model results indicate that the cyclone influences the marine planktonic ecosystem by enhancing productivity on the shelves of the Chukchi, East Siberian, and Laptev seas during the storm. Although the cyclone's passage in the PSA lasted only a few days, the simulated biological effects on the shelves last 1 month or longer. At some locations on the shelves, primary productivity (PP) increases by up to 90% and …

Lack Of Equivalence In The Elemental And Stable Isotope Chemistry Within The Sagittal Otolith Pair Of The Summer Flounder, Paralichthys Dentatus, Antranik Kajajian, Jason J. Schaffler, Cynthia M. Jones

OES Faculty Publications

In fish that are not bilaterally symmetrical, the left and right sagittae are often not symmetrical, exhibiting divergent growth patterns and mass, and may have differences in chemical composition. We investigated this in the asymmetrical summer flounder Paralichthys dentatus, collected from different nursery habitats along the US east coast. Significant differences were detected in otolith mass, δ¹³C, δ¹⁸O, Li:Ca, Mg:Ca, and Sr:Ca, and overall chemical signatures. These results refute the hypothesis of left-right equivalence that is prevalent for bilaterally symmetrical fishes. We tested whether a specific side was better suited for classification. The best models …

Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones

OES Faculty Publications

The importance of estuarine seagrass beds as nurseries for juvenile fish has become a universal paradigm, especially for estuaries that are as important as the Chesapeake Bay. Yet, scientific tests of this hypothesis were equivocal depending on species, location, and metrics. Moreover, seagrasses themselves are under threat and one-third of seagrasses have disappeared worldwide with 65 of their losses occurring in estuaries. Although there have been extensive studies of seagrasses in the Chesapeake Bay, surprisingly few studies have quantified the relationship between seagrass as nurseries for finfish in the Bay. Of the few studies that have directly evaluated the use …

Emergence Of Algal Blooms: The Effects Of Short-Term Variability In Water Quality On Phytoplankton Abundance, Diversity, And Community Composition In A Tidal Estuary, Todd A. Egerton, Ryan E. Morse, Harold G. Marshall, Margaret R. Mulholland

OES Faculty Publications

Algal blooms are dynamic phenomena, often attributed to environmental parameters that vary on short timescales (e.g., hours to days). Phytoplankton monitoring programs are largely designed to examine long-term trends and interannual variability. In order to better understand and evaluate the relationships between water quality variables and the genesis of algal blooms, daily samples were collected over a 34 day period in the eutrophic Lafayette River, a tidal tributary within Chesapeake Bay's estuarine complex, during spring 2006. During this period two distinct algal blooms occurred; the first was a cryptomonad bloom and this was followed by a bloom of the mixotrophic …

Reproductive Phase Determination In Male Meagre (Argyrosomus Regius, Sciaenidae): Testis Development And Histologic Corroboration Of A Gross Anatomical Scale, Nuno Prista, Leonel Gordo, José Lino Costa, Maria José Costa, Cynthia Jones

OES Faculty Publications

Reproductive stage determination of male gonads has received sparse attention in fish biology literature with few studies detailing the building of gross anatomical- and histologic scales. The meagre (Argyrosomus regius) is one of the world's largest sciaenids and supports a significant regional fishery in European and North African waters whose reproductive patterns are yet to be fully investigated. In the present study, we derive a macroscopic grading system for meagre testis using semi-quantitative graphs that feature the testis variability along the species size range and time of the year. We then describe the histological stages and reproductive phases of male …

Detection Of Seagrass Scars Using Sparse Coding And Morphological Filter, Ender Oguslu, Sertan Erkanli, Victoria J. Hill, W. Paul Bissett, Richard C. Zimmerman, Jiang Li, Charles R. Bostater Jr. (Ed.), Stelios P. Mertikas (Ed.), Xavier Neyt (Ed.)

OES Faculty Publications

We present a two-step algorithm for the detection of seafloor propeller seagrass scars in shallow water using panchromatic images. The first step is to classify image pixels into scar and non-scar categories based on a sparse coding algorithm. The first step produces an initial scar map in which false positive scar pixels may be present. In the second step, local orientation of each detected scar pixel is computed using the morphological directional profile, which is defined as outputs of a directional filter with a varying orientation parameter. The profile is then utilized to eliminate false positives and generate the final …