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Articles 10621 - 10650 of 14040

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

The William S. Richardson Library, Nova Southeastern University Jan 2005

The William S. Richardson Library, Nova Southeastern University

Halmos College of Natural Sciences and Oceanography Course Catalogs

No abstract provided.


The National Coral Reef Institute, Nova Southeastern University Jan 2005

The National Coral Reef Institute, Nova Southeastern University

Halmos College of Natural Sciences and Oceanography Course Catalogs

No abstract provided.


Landscape Patterns Of Streams & Lakes In Montane Watersheds Determine Water Temperatures & Nutrient Transport: Watershed Analyses And N Tracer Experiments, Wayne A. Wurtsbaugh, J. Garrett, G. Burkart, W. Fleenor, K. Nydick, R. Hall, Michelle A. Baker Jan 2005

Landscape Patterns Of Streams & Lakes In Montane Watersheds Determine Water Temperatures & Nutrient Transport: Watershed Analyses And N Tracer Experiments, Wayne A. Wurtsbaugh, J. Garrett, G. Burkart, W. Fleenor, K. Nydick, R. Hall, Michelle A. Baker

Watershed Sciences Faculty Publications

In glaciated mountains, lakes are interspersed through watersheds and connected by streams. Although lakes or streams are frequently studied as individual water bodies, studying them as integrated functional units provides considerable insight on temperature patterns, nutrient transport and other functions. In the Sawtooth Mountains (Idaho), inter-lake distance averages 2.8 km. In summer, lakes are solar collectors, and warm outflow streams as much as 10 C, thus increasing metabolic rates. These streams seldom cool to equilibrium temperatures before encountering another lake, where the waters tend to overflow and mix into the epilimnion. With overflow, N-15 tracer experiments demonstrated that water and …


An Analysis Of Nitrate Contaminated Water In Cherry Valley, Adriana Hernandez-Romo Jan 2005

An Analysis Of Nitrate Contaminated Water In Cherry Valley, Adriana Hernandez-Romo

Theses Digitization Project

The purpose of this study was to evaluate the level of nitrate contamination in the water in Cherry Valley. It examines the theory that human effluent is the source of the nitrate and evaluates the role of politics in the nitrate issue.


On The Optimization Of Visualizations Of Complex Phenomena, Donald H. House, Althea D. Bair, Colin Ware Jan 2005

On The Optimization Of Visualizations Of Complex Phenomena, Donald H. House, Althea D. Bair, Colin Ware

Center for Coastal and Ocean Mapping

The problem of perceptually optimizing complex visualizations is a difficult one, involving perceptual as well as aesthetic issues. In our experience, controlled experiments are quite limited in their ability to uncover interrelationships among visualization parameters, and thus may not be the most useful way to develop rules-of-thumb or theory to guide the production of high-quality visualizations. In this paper, we propose a new experimental approach to optimizing visualization quality that integrates some of the strong points of controlled experiments with methods more suited to investigating complex highly-coupled phenomena. We use human-in-the-loop experiments to search through visualization parameter space, generating large …


Mapping Near-Surface Gas With Acoustic Remote Sensing Methods, Examples From Eel River Margin, Ca And Skjalfandi Bay, Iceland, Luciano E. Fonseca, Larry A. Mayer Jan 2005

Mapping Near-Surface Gas With Acoustic Remote Sensing Methods, Examples From Eel River Margin, Ca And Skjalfandi Bay, Iceland, Luciano E. Fonseca, Larry A. Mayer

Center for Coastal and Ocean Mapping

No abstract provided.


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


Multiple-Year Droughts In Nebraska, Michael J. Hayes, Cody L. Knutson, Q. Steven Hu Jan 2005

Multiple-Year Droughts In Nebraska, Michael J. Hayes, Cody L. Knutson, Q. Steven Hu

National Drought Mitigation Center: Faculty Publications

Most people understand that droughts have had a major impact on Nebraska in the past. Yet, many Nebraskans continue to be surprised when drought occurs. It is important to remember that droughts, including multiple-year droughts, are a normal part of Nebraska’s climate. This NebGuide discusses the history of drought in Nebraska, and aims to help Nebraskans better understand the range of climatic variability when they plan for drought.


Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson Jan 2005

Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson

National Drought Mitigation Center: Faculty Publications

Past attempts to manage drought and its impacts through a reactive, crisis management approach have been ineffective, poorly coordinated, and untimely, as illustrated by the hydro- illogical cycle in Figure 1. The crisis management approach has been followed in both developed and developing countries. Because of the ineffectiveness of this approach, greater interest has evolved in recent years in the adoption of a more proactive risk-based management approach in some countries (see Chapter 6). Other countries are striving to obtain a higher level of preparedness through development of national action programs that are part of the United Nations Convention to …


A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes Jan 2005

A New Approach For Predicting Drought-Related Vegetation Stress: Integrating Satellite, Climate, And Biophysical Data Over The U.S. Central Plains, Tsegaue Tadesse, Jesslyn F. Brown, Michael Hayes

National Drought Mitigation Center: Faculty Publications

Droughts are normal climate episodes, yet they are among the most expensive natural disasters in the world. Knowledge about the timing, severity, and pattern of droughts on the landscape can be incorporated into effective planning and decisionmaking. In this study, we present a data mining approach to modeling vegetation stress due to drought and mapping its spatial extent during the growing season. Rule-based regression tree models were generated that identify relationships between satellite-derived vegetation conditions, climatic drought indices, and biophysical data, including land-cover type, available soil water capacity, percent of irrigated farm land, and ecological type. The data mining method …


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 Jan 2005

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 …


The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers Jan 2005

The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers

United States Geological Survey: Staff Publications

Jarosite-group minerals accumulate in the form of stalactites and fine-grained mud on massive pyrite in the D drift of the Richmond mine, Iron Mountain, California. Water samples were collected by placing beakers under the dripping stalactites and by extracting pore water from the mud using a centrifuge. The water is rich in Fe3+ and SO42–, with a pH of approximately 2.1, which is significantly higher than the extremely acidic waters found elsewhere in the mine. Electron-microprobe analysis and X-ray mapping indicate that the small crystals (<10 > μm in diameter) are compositionally zoned with respect to Na …


Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins Jan 2005

Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins

United States Geological Survey: Staff Publications

Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …


Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton Jan 2005

Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton

United States Geological Survey: Staff Publications

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of …


Discovering Associations Between Climatic And Oceanic Parameters To Monitor Drought In Nebraska Using Data-Mining Techniques, Tsegaye Tadesse, Donald A. Wilhite, Michael J. Hayes, Steve Goddard Jan 2005

Discovering Associations Between Climatic And Oceanic Parameters To Monitor Drought In Nebraska Using Data-Mining Techniques, Tsegaye Tadesse, Donald A. Wilhite, Michael J. Hayes, Steve Goddard

National Drought Mitigation Center: Faculty Publications

Drought is a complex natural hazard that is best characterized by multiple climatological and hydrological parameters. Improving our understanding of the relationships between these parameters is necessary to reduce the impacts of drought. Data mining is a recently developed technique that can be used to interact with large databases and assist in the discovery of associations between drought and oceanic data by extracting information from massive and multiple data archives. In this study, a new data-mining algorithm [i.e., Minimal Occurrences With Constraints and Time Lags (MOWCATL)] has been used to identify the relationships between oceanic parameters and drought indices. Rather …


Winter 2005, Nsu Oceanographic Center Jan 2005

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 Jan 2005

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 Jan 2005

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 Jan 2005

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 …


Quantification And Prediction Of Stream Dryness In The Interior Highlands, Justin M. Homan, Nicholas M. Girondo, Charles J. Gagen Jan 2005

Quantification And Prediction Of Stream Dryness In The Interior Highlands, Justin M. Homan, Nicholas M. Girondo, Charles J. Gagen

Journal of the Arkansas Academy of Science

Although ecological studies have noted streams drying in the Interior Highlands, published measurements of streambed dryness are lacking. Clearly, stream drying has the potential to affect benthic macroinvertebrate and fish communities. In 2003, we initiated an assessment of streambed dryness for three streams in the Ouachita Mountains representative of the Central Hills, Ridges, and Valleys. In the following summer, we applied the approach to 15 similar size watersheds in three distinct ecoregions of the Interior Highlands: Ouachita Mountains-Athens Plateau, Ozark Highlands-Springfield Plateau, and Lower Boston Mountains. Repeated dryness measurements were recorded in each stream and correlated to nearby USGS stream …


A Comparison Between Monte Carlo Simulations Of Runaway Breakdown And Terrestrial Gamma-Ray Flash Observations, Joseph R. Dwyer, David M. Smith Jan 2005

A Comparison Between Monte Carlo Simulations Of Runaway Breakdown And Terrestrial Gamma-Ray Flash Observations, Joseph R. Dwyer, David M. Smith

Aerospace, Physics, and Space Science Faculty Publications

Monte Carlo simulations of the runaway breakdown of air are used to calculate the spectra of terrestrial gamma-ray flashes (TGFs), which are then compared with RHESSI and CGRO/BATSE observations. It is found that the recent RHESSI spectrum is not consistent with a source altitude above 24 km but can be well fit by a source in the range of 15-21 km, depending upon the electric field geometry of the source. Because 15 km is not unusual for the tops of thunderstorms, especially at low latitudes, and is lower than typical minimum sprite altitudes, the RHESSI data imply that thunderstorms and …


X-Ray Bursts Produced By Laboratory Sparks In Air, Joseph R. Dwyer, Hamid K. Rassoul, Ziad H. Saleh, Martin A. Uman, J. Jerauld, J. Anderson Plumer Jan 2005

X-Ray Bursts Produced By Laboratory Sparks In Air, Joseph R. Dwyer, Hamid K. Rassoul, Ziad H. Saleh, Martin A. Uman, J. Jerauld, J. Anderson Plumer

Aerospace, Physics, and Space Science Faculty Publications

X-ray observations were made during fourteen 1.5 to 2.0 m high-voltage discharges in air produced by a 1.5 MV Marx circuit. All 14 discharges generated x-rays in the ∼30 to 150 keV range. The x-rays, which arrived in discrete bursts, less than 0.5 microseconds in duration, occurred from both positive and negative polarity rod-to-plane discharges as well as from small, 5-10 cm series spark gaps within the Marx generator. The x-ray bursts usually occurred when either the voltages across the gaps were the largest or were in the process of collapsing. The bursts are remarkably similar to the x-ray bursts …


The Initiation Of Lightning By Runaway Air Breakdown, Joseph R. Dwyer Jan 2005

The Initiation Of Lightning By Runaway Air Breakdown, Joseph R. Dwyer

Aerospace, Physics, and Space Science Faculty Publications

A mechanism for lightning initiation by the sustained runaway breakdown of air is presented. Unlike earlior models that rely upon large cosmic-ray air showers, this mechanism uses the runaway electrons produced by the steady background of atmospheric cosmic-rays to amplify non-uniformities in the electric field. The ionization of air from the runaway electrons creates a region of discharge that propagates in the opposite direction of the electrons, enhancing the electric field in front of it to the point where a conventional breakdown can occur. As the discharged region grows, positron feedback can become important, dramatically increasing the flux of runaway …


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


Quantification And Prediction Of Stream Dryness In The Interior Highlands, Justin M. Homan, Nicholas M. Girondo, Charles J. Gagen Jan 2005

Quantification And Prediction Of Stream Dryness In The Interior Highlands, Justin M. Homan, Nicholas M. Girondo, Charles J. Gagen

Faculty Publications - Biological Sciences

Although ecological studies have noted streams drying in the Interior Highlands, published measurements of streambed dryness are lacking. Clearly, stream drying has the potential to affect benthic macroinvertebrate and fish communities. In 2003, we initiated an assessment of streambed dryness for three streams in the Ouachita Mountains representative of the Central Hills, Ridges, and Valleys. In the following summer, we applied the approach to 15 similar size watersheds in three distinct ecoregions of the Interior Highlands: Ouachita Mountains-Athens Plateau, Ozark Highlands-Springfield Plateau, and Lower Boston Mountains. Repeated dryness measurements were recorded in each stream and correlated to nearby USGS stream …


Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee Jan 2005

Demonstration Of Toxicity To Fish And To Mammalian Cells By Pfiesteria Species: Comparison Of Assay Methods And Strains, Joann M. Burkholder, Andrew S. Gordon, Peter D. Moeller, J. Mac Law, Kathryn J. Coyne, Alan J. Lewitus, John S. Ramsdell, Harold G. Marshall, Nora J. Deamer, S. Craig Cary, Jason W. Kempton, Steven L. Morton, Parke A. Rublee

Biological Sciences Faculty Publications

Toxicity and its detection in the dinoflagellate fish predators Pfiesteria piscicida and Pfiesteria shumwayae depend on the strain and the use of reliable assays. Two assays, standardized fish bioassays (SFBs) with juvenile fish and fish microassays (FMAs) with larval fish, were compared for their utility to detect toxic Pfiesteria. The comparison included strains with confirmed toxicity, negative controls (noninducible Pfiesteria strains and a related nontoxic cryptoperidiniopsoid dinoflagellate), and P. shumwayae strain CCMP2089, which previously had been reported as nontoxic. SFBs, standardized by using toxic Pfiesteria (coupled with tests confirming Pfiesteria toxin) and conditions conducive to toxicity expression, reliably detected …


Seasonal Variability Of Near-Surface Hydrography And Frontal Features In The Northern Gulf Of Alaska And Prince William Sound, Stephen R. Okkonen, David L. Cutchin, Thomas Royer Jan 2005

Seasonal Variability Of Near-Surface Hydrography And Frontal Features In The Northern Gulf Of Alaska And Prince William Sound, Stephen R. Okkonen, David L. Cutchin, Thomas Royer

CCPO Publications

The meridional structure and seasonal cycles of near-surface hydrography and frontal features in the northern Gulf of Alaska and Prince William Sound are described from high-resolution measurements of near-surface temperature and salinity acquired by a vessel-mounted thermosalinograph. Near-surface temperature exhibits a well-defined seasonal cycle with little variation between basin and shelf waters. Near-surface salinity exhibits a well-defined seasonal cycle that is confined largely to the shelf waters reflecting the influence of coastal freshwater inputs. Prominent near-surface fronts at the shelf break, at the entrance to Prince William Sound, and in northern Prince William Sound intensify and weaken following the seasonal …


Flowers Of Ice- Beauty, Symmetry, And Complexity: A Review Of The Snowflake: Winter's Secret Beauty, John A. Adam Jan 2005

Flowers Of Ice- Beauty, Symmetry, And Complexity: A Review Of The Snowflake: Winter's Secret Beauty, John A. Adam

Mathematics & Statistics Faculty Publications

(First paragraph) Growing up as a child in southern England, my early memories of snow include trudging home from school with my father, gazing at the seemingly enormous snowdrifts that smoothed the hedgerows, fields and bushes, while listening to the soft “scrunch” of the snow under my Wellington boots. In the country, snow stretching as far as I could see was not a particularly uncommon sight. The quietness of the land under a foot of snow seemed eerie. I cannot remember the first time I looked at snowflakes per se; my interests as a small child were primarily in their …


A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture Jan 2005

A Review Of Phytoplankton Composition Within Chesapeake Bay And Its Tidal Estuaries, Harold G. Marshall, Lubomira Burchardt, Richard Lacouture

Biological Sciences Faculty Publications

Based on a continuous 20-year data base ofmonthly sampling in Chesapeake Bay and tidal regions of its major tributaries, 1454 phytoplankton taxa have been identified in these waters. They represent a diverse assemblage of species with a dominant diatom flora throughout the year, in addition to large seasonal representation by chlorophytes, cyanobacteria, cryptophytes and dinoflagellates. Included among this flora were 34 potential harmful or toxin producing species. The phytoplankton compositions associated with the seasonal successional patterns are discussed, in addition to characterizing the dominant floral relationships, with comparison to early composition records within the Bay. Several of the present day …


Detailed Geochronology Of The Mississippi Sound During The Late Holocene, Brian Velardo Jan 2005

Detailed Geochronology Of The Mississippi Sound During The Late Holocene, Brian Velardo

LSU Master's Theses

The Mississippi Sound is a bar-built estuary that parallels the Mississippi Coast. It is bounded on the west by the St. Bernard lobe of the Mississippi River delta, Mobile Bay to the east, and the Gulf Coast barrier islands to the south. Few studies have investigated the late Holocene history of Mississippi Sound. In the present study, historical deposition in the Sound has been investigated using core data collected throughout the western, central, and eastern Mississippi Sound. The sediments within Mississippi Sound compose a complex depositional system that have responded to changes in sea level and hydrodynamics. Two factors that …