Oceanography and Atmospheric Sciences and Meteorology Commons^™

Evaluating The Biogeochemical Cycle Of Selenium In San Francisco Bay Through Modeling, Shannon L. Meseck, Gregory A. Cutter

OES Faculty Publications

A biogeochemical model was developed to simulate salinity, total suspended material, phytoplankton biomass, dissolved selenium concentrations (selenite, selenate, and organic selenide), and particulate selenium concentrations (selenite + selenate, elemental selenium, and organic selenide) in the San Francisco Bay estuary. Model-generated estuarine profiles of total dissolved selenium reproduced observed estuarine profiles at a confidence interval of 91- 99% for 8 different years under various environmental conditions. The model accurately reproduced the observed dissolved speciation at confidence intervals of 81-98% for selenite, 72-91% for selenate, and 60-96% for organic selenide. For particulate selenium, model-simulated estuarine profiles duplicated the observed behavior of total …

Dynamics Of Carbon Allocation In A Deep-Water Population Of The Deciduous Kelp Pleurophycus Gardeneri (Laminariales), Clare M. Dominik, Richard C. Zimmerman

OES Faculty Publications

Pleurophycus gardneri (Laminariales) is common in the low intertidal of the Northeast Pacific, but dominates many deep (30 to 40 m) rocky reefs in central California. Seasonal dynamics of productivity and resource allocation of a deep-water population of this deciduous, stipitate kelp were studied to understand how blade abscission affects the annual carbon budget. Patterns of growth, metabolism, and carbon storage and mobilization were measured monthly for 1 yr relative to in situ light and temperature, and used to model the annual carbon budget. The resulting carbon budget was used to determine if blade abscission effectively reduced respiratory demand during …

Red And Black Tides: Quantitative Analysis Of Water-Leaving Radiance And Perceived Color For Phytoplankton, Colored Dissolved Organic Matter, And Suspended Sediments, Heidi M. Dierssen, Raphael M. Kudela, John P. Ryan, Richard C. Zimmerman

OES Faculty Publications

Using field measurements and quantitative modeling, we demonstrate that red coloration of the sea surface is not associated with any particular group of phytoplankton and is strongly dependent on the physiology of the human visual system. Red or brown surface waters can be produced by high concentrations of most types of algae, colored dissolved organic matter, or suspended sediment. Even though light reflected by red tides commonly peaks in the yellow spectral region (570–580 nm), human color perception requires consideration of the entire spectrum of light relative to receptors within the human eye. The color shift from green to red …

The Role Of Lipids During Embryonic Development Of The Euphausiids Euphausia Pacifica And Thysanoessa Spinifera, Se-Jong Ju, H. Rodger Harvey, Jaime Gómez-Gutiérrez, William T. Peterson

OES Faculty Publications

To understand the role of lipids during early embryogenesis, major lipid classes together with individual fatty acid and sterol composition were determined in embryos from multiple developmental stages of the euphausiids Euphausia pacifica and Thysanoessa spinifera. Average lipid content in embryos of E. pacifica and T. spiniferafrom the earliest stage (multicell) were 4.45 and 3.69 µg embryo^-1,respectively. During development, the lipid content decreased at similar rates in the embryos of both species. In contrast to many crustacean eggs, phospholipids were the dominant lipid class in all embryonic stages, with decreasing concentrations seen during development. Individual …

Nitrogen Fixation And Release Of Fixed Nitrogen By Trichodesmium Spp. In The Gulf Of Mexico, Margaret R. Mulholland, Peter W. Bernhardt, Cynthia A. Heil, Deborah A. Bronk, Judith M. O'Neil

OES Faculty Publications

During a 3-yr study in the Gulf of Mexico, we measured dinitrogen (N₂) fixation and nitrogen (N) release by Trichodesmium and compared these rates with water column N demand and the estimated N necessary to support blooms of Karenia brevis, a toxic dinoflagellate that severely affects the West Florida shelf. Net and gross N₂ fixation rates were compared in simultaneous incubations using ¹⁵N₂ uptake and acetylene reduction, respectively. The difference between net and gross N₂ fixation is assumed to be an approximation of the rate of N release. Results demonstrate that Trichodesmium in …

Winter 2006, Nsu Oceanographic Center

Currents

No abstract provided.

Ocean Warming And Freshening In The Northern Gulf Of Alaska, Thomas C. Royer, Chester E. Grosch

CCPO Publications

Water column temperatures on the shelf in the northern Gulf of Alaska have increased more than 0.8 degrees C and vertical density stratification has increased since 1970 near Seward, Alaska throughout the 250 m depth. This high latitude marine system has low water temperatures, high rates of precipitation, glacial melting, high wind speeds and high rates of biological productivity. A more than 300 km alongshore shift ( locally westward) of isotherms is suggested. The observations are consistent with a conceptual ocean-atmosphere circulation model that employs coastal freshwater discharge, glacial ablation and wind forcing. Positive regional feedback mechanisms accelerate the discharge …

The Influence Of Supplemental Feeding On The Movement Patterns Of The Southern Stingray, Dasyatis Americana, At Grand Cayman, Cayman Islands, Mark John Corcoran

HCNSO Student Theses and Dissertations

There are currently over 300 sites in nearly 40 countries where a variety of marine animals are provided supplemental food by humans. The influence of this supplemental feeding on the behavior, physiology, growth, reproduction and movements of the animals involved is seldom known. Intentional supplemental feeding of the southern stingray, Dasyatis americana, has occurred at Stingray City (SC) and Stingray City Sandbar (SCS) at Grand Cayman since 1986. There are no specific regulations governing the feeding of D. americana at Grand Cayman, and neither the species nor the feeding sites are afforded any official protective status. This study investigated …

Transport Of Antarctic Krill (Euphausia Superba) Across The Scotia Sea. Part Ii: Krill Growth And Survival, Bettina A. Fach, Eileen E. Hofmann, Eugene J. Murphy

CCPO Publications

A time-dependent, size-structured, physiologically based krill growth model was used in conjunction with a circulation model to test the hypothesis that Antarctic krill (Euphausia superba) populations at South Georgia are sustained by import of individuals from upstream regions. Surface phytoplankton concentrations along the simulated drifter trajectories were extracted from historical Coastal Zone Color Scanner (CZCS) measurements and sea ice biota concentrations were calculated from sea ice concentration and extent extracted along drifter trajectories from Special Sensor Microwave/ Imager measurements. As additional food sources, a time series of heterotrophic food was constructed from historical data, and time series of …

Vertical Distribution Of Decapod Larvae In The Entrance Of An Equatorward Facing Bay Of Central Chile: Implications For Transport, Beatriz Yannicelli, Leonardo R. Castro, Arnoldo Valle-Levinson, Larry Atkinson, Dante Figueroa

CCPO Publications

Two short biophysical surveys were carried out in order to assess how the decapod crustacean larvae vertical distribution and circulation patterns in an equatorward facing embayment (Gulf of Arauco, 37° S; 73° W) influenced larval transport into and out of the Gulf. The embayment is located at the upwelling area of south central Chile and features a deep (60 m) and a shallow (25 m) pathway of communication with the adjacent coastal ocean. Profiles of zooplankton, temperature, salinity, dissolved oxygen and current velocity were measured during a 22-h period at the shallow entrance to the gulf. In addition, three zooplankton …

Effects Of Salinity Changes On The Photodegradation And Ultraviolet-Visible Absorbance Of Terrestrial Dissolved Organic Matter, E. C. Minor, J. Pothen, B. J. Dalzell, H. Abdulla, K. Mopper

Chemistry & Biochemistry Faculty Publications

We performed laboratory studies to determine the effects of salinity on the photodegradation of dissolved organic matter (DOM) from the Great Dismal Swamp, Virginia, an important source of terrestrial DOM to the lower Chesapeake Bay. Samples were created by mixing Great Dismal Swamp water (ionic strength approximate to 0 mol L^-1) with modified artificial seawater solutions of differing salinities while keeping the final dissolved organic carbon (DOC) concentration constant. These samples were then irradiated for 24 h in a light box providing ultraviolet (UV) light similar to that of natural sunlight. Light absorbance and DOC concentrations decreased after …

The Sedimentary Environment Below Earth’S Polar Ice Cap As A Microbial Habitat, David C. Smith, Stephanie Forschner-Dancause, David C. Rowley, Steven D'Hondt

Graduate School of Oceanography Faculty Publications

University of Rhode Island faculty participated in drilling of the polar ice cap to study microbial diversity and adaptation to subsurface life under conditions that may mimic extraterrestrial subsurface conditions.

Distribution Of Foraging Shearwaters Relative To Inner Front Of Se Bering Sea, J. Jahncke, K. O. Coyle, Stephan I. Zeeman, N. B. Kachel, G. L. Hunt Jr.

Marine Sciences Faculty Publications

We examined the hypothesis that short-tailed shearwaters Puffinus tenuirostris aggregate to forage at the inner front of the SE Bering Sea because of enhanced production there. We tested this hypothesis by comparing primary production, the distribution of euphausiids and the distribution of shearwaters relative to the front during late spring and late summer/early fall of 1997, 1998 and 1999. We found enhanced primary production at the front and offshore of the front during summer but not during spring. Primary production varied between seasons and years. Major differences were related to anomalous conditions in 1997 and 1998. The density of euphausiids …

Estimation Of Iron Solubility From Observations And A Global Aerosol Model, Chao Luo, N. M. Mahowald, N. Meskhidze, Y. Chen, R. L. Siefert, A. R. Baker, Anne M. Johansen

All Faculty Scholarship for the College of the Sciences

Mineral aerosol deposition is the dominant source of iron to the open ocean. Soil iron is typically insoluble and understanding the atmospheric processes that convert insoluble iron to the more soluble forms observed over the oceans is crucial. In this paper, we model several proposed processes for the conversion of Fe(III) to Fe(II), and compare with cruise observations. The comparisons show that the model results in similar averaged magnitudes of iron solubility as measured during 8 cruises in 2001–2003. Comparisons show that results of cases including cloud, SO₂ and hematite processing are better than the other approaches used using …

Monthly Variability In Florida Bay Benthic Foraminifera Community Structure, C. Featherstone, Patricia Blackwelder

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Florida Bay is a shallow subtropical estuary, which experiences highly variable environmental fluctuations due to natural forces (hurricanes, climatic variations and sea level rise) and anthropogenic influences (agricultural activity, water management and urbanization). Study of short time-scale variability in benthic community population structure and synchronous environmental change is essential to understanding forcing relationships between environment and its effects on population. Benthic foraminifera assemblage variability is an excellent indicator of environmental change in estuarine and coastal areas because populations may respond relatively quickly on spatial and temporal scales (Alve, 1995). Temporal resolution is enhanced because foraminifera may reproduce as often as …

Fall 2005, Nsu Oceanographic Center

Currents

No abstract provided.

Characterization Of Pfiesteria Ichthyocidal Activity, Andrew S. Gordon, Harold G. Marshall, Sandra E. Shumway, Kathryn J. Coyne, Alan J. Lewitus, Michael A. Mallin, Parke A. Rublee

Biological Sciences Faculty Publications

Letter to the Editor regarding article: Drgon, T., et al. 2005. Characterization of ichthyocidal activity of Pfiesteria piscicida: Dependence on the dinospore cell density. Appl. Environ. Microbiol. 71:519–529

A Comparison Of Diets And Water Agitation Methods For Larval Culture Of The Edible Sea Urchin, Tripneustes Ventricosus (Echinodermata: Echinoidea), Ray Wolcott, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

Tripneustes ventricosus (Lamarck, 1816) has been harvested for human consumption in the Caribbean for centuries, where harvest rates occasionally exceed sustainability. Historically a backreef and grass-bed urchin, the species has recently been observed on the forereef where it appears to control macroalgal growth in the absence of Diadema antillarum (Philippi, 1845) (Woodley and Gayle, 1999). Large-scale culturing has the potential to produce T. ventricosus in sufficient numbers for remediation of degraded coral reefs, restocking of nearshore habitats, and development of an aquaculture industry for one or more Caribbean islands. We report the first successful culturing of T. ventricosus from fertilization …

Summer 2005, Nsu Oceanographic Center

Currents

No abstract provided.

Phytoplankton Development Within Tidal Freshwater Regions Of Two Virginia Rivers, Harold G. Marshall, Lubomira Burchardt

Virginia Journal of Science

Phytoplankton composition and the range of seasonal patterns of abundance are presented for the tidal freshwater regions in two Virginia rivers based on data accumulated monthly from 1986 through 1999. Diatoms dominated the flora during spring, summer, and fall, whereas, other taxonomic categories were more representative when the river flow rates decreased, allowing for a more stable water system and increased residency time within this tidal region during summer and early fall. This summer/fall period was associated with increased water temperatures, higher productivity rates and chlorophyll levels, increased total phytoplankton abundance and species diversity. The major components of the summer …

Southeast Florida Coral Reef Evaluation And Monitoring Project 2004 Year 2 Final Report, Jennifer Wheaton, Carl Beaver, Walter Jaap, Michael Callahan, Selena Kupfner, Shannon Wade, Jim Kidney, Stopher Slade, Erin Mcdevitt, Eric Ault, Fred Voss, David S. Gilliam, B. D. Ettinger, Daniel P. Fahy, Elizabeth Glynn Fahy, Shaun M. Gill, Jamie A. Monty, Lauren F. Shuman, Brian K. Walker, Richard E. Dodge, Tim Mcintosh, Steven Blair, Kenneth Banks, Louis E. Fisher, David Stout, Joe Ligas, Janet Phipps

Marine & Environmental Sciences Faculty Reports

No abstract provided.

Development Of An Underwater Infrared Camera To Detect Manatees, Edward O. Keith

Marine & Environmental Sciences Faculty Reports

In calendar year 2004, watercraft related mortality was the second leading cause of death of the Florida manatee (Trichechus manatus latirostris) accounting for 25% of total known manatee deaths. In an attempt to reduce this significant cause of manatee mortality, the Florida Fish and Wildlife Research Institute has instituted two rounds of Manatee Avoidance Technology grants. Herein I report the results of an evaluation of the ability of underwater infrared video cameras to detect captive manatees and other non-living targets. If such cameras could detect manatees at sufficient distances, they could be mounted in the bows of watercraft …

Coral Recruitment Patterns In The Florida Keys, Alison L. Moulding

Marine & Environmental Sciences Faculty Articles

This study examines scleractinian zooxanthellate coral recruitment patterns in the Florida Keys to determine if differences in density or community composition exist between regions. From July to September 2002, nine patch reefs, three in each of the upper, middle and lower Keys, were surveyed for coral recruits (colonies <5 cm in diameter) using randomly placed quadrats and transects. Coral recruits were enumerated, measured, and identified to genus. Fourteen genera of corals were observed across all sites and ranged from five to 13 per site. Densities ranged from 6.29 ± 1.92 (mean ± SE) to 39.08 ± 4.53 recruits m-2, and there were significant site and regional differences in recruit densities. The density of recruits in the upper Keys was significantly lower than in the middle and lower Keys. In addition, the upper Keys were less diverse and had a different recruit size-frequency distribution. The majority of recruits were non-massive scleractinian species that contribute relatively little to overall reef-building processes, a finding that is similar to previous studies. Fewer recruits of massive species were found in the upper Keys compared to the middle and lower Keys. The recruitment patterns of the reefs in the upper Keys could potentially hinder their ability to recover from stress and disturbances.

Spring 2005, Nsu Oceanographic Center

Currents

No abstract provided.

Fish Colonization Of A Newly Deployed Vessel-Reef Off Southeast Florida: Preliminary Results, Paul T. Arena, Lance K. B. Jordan, Patrick Quinn, Arlo H. Hemphill, David R. Bryan, Brian Buskirk, Richard E. Spieler

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Fish colonization on the Ebenezer II, a 25.5m merchant marine vessel, was studied from May 2002 - July 2003. The ship was scuttled in May 2002 off Broward County, Florida at a depth of 21m and was censused 10 times during the study period using a modified Bohnsack and Bannerot visual census method. Adjacent natural reefs and the Mcallister, a nearby, 30m tugboat deployed in June 1998, were censused during the same period.

Distinct changes in the fish assemblage on the Ebenezer II were observed throughout the sample period. A pioneer assemblage was observed during the first three months, characterized …

Winter 2005, Nsu Oceanographic Center

Currents

No abstract provided.

The State Of Coral Reef Ecosystems Of Florida, Katherine Andrews (Ed.), Larry Nall (Ed.), Chris Jeffrey (Ed.), Simon Pittman (Ed.), Kenneth Banks, Carl Beaver, James A. Bohnsack, Richard E. Dodge, David S. Gilliam, Walter Jaap, Brian Keller, V. R. Leeworthy, Tom Matthews, Ramon Ruiz-Carus, Deborah Santavy, Richard E. Spieler, Jerald Ault, Gabriel Delgado, Fleur M. Ferro, Carol R. Fretwell, Bill Goodwin, Doug Harper, John Hunt, Margaret Miller, Christy Pattengil-Semmens, Bill Sharp, Steve Smith, Jennifer Wheaton, Dana Williams

Marine & Environmental Sciences Faculty Reports

No abstract provided.

Sea Turtle Conservation Program, Broward County, Fl 2005 Report, Curtis M. Burney, Stefanie Ouellette

Marine & Environmental Sciences Faculty Reports

No abstract provided.

Highly Streamlined Pcr-Based Genetic Identification Of Carcharhinid Sharks (Family Carcharhinidae) For Use In Wildlife Forensics, Trade Monitoring, And Delineation Of Species Distributions, Marcy Henning

HCNSO Student Theses and Dissertations

An increase in worldwide industrialized shark fisheries resulting from the growing demand for shark products, especially shark fins in Asian markets, as well as high levels of bycatch mortality associated with multi-species fisheries have raised suspicions of substantial declines in global shark populations. Due to varying responses by individual species to fishing pressure, it has become necessary to manage sharks on a species-specific basis, which requires the collection of more accurate catch and trade data. The accumulation of such data is hindered, however, by difficulties in identifying species from only landed carcasses, body parts, or fins. This is especially true …

Iron In The Sargasso Sea (Bermuda Atlantic Time-Series Study Region) During Summer: Eolian Imprint, Spatiotemporal Variability, And Ecological Implications, Peter N. Sedwick, T. M. Church, A. R. Bowie, C. M. Marsay, S. J. Ussher, K. M. Achilles, P. J. Lethaby, R. J. Johnson, M. M. Sarin, D. J. Mcgillicuddy

OES Faculty Publications

We report iron measurements for water column and aerosol samples collected in the Sargasso Sea during July-August 2003 (summer 2003) and April-May 2004 (spring 2004). Our data reveal a large seasonal change in the dissolved iron (dFe) concentration of surface waters in the Bermuda Atlantic Time-series Study region, from ∼1-2nM in summer 2003, when aerosol iron concentrations were high (mean 10 nmol/m^-3), to ∼0.1-0.2nM in spring 2004, when aerosol iron concentrations were low (mean 0.64 nmol/m^-3). During summer 2003, we observed an increase of ∼0.6nM in surface water dFe concentrations over 13 days, presumably due to …