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Full-Text Articles in Physical Sciences and Mathematics
Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski
Fishes In Seagrass Habitats: Species Composition, Trophic Interactions, And Production, Kathryn L. Sobocinski
Dissertations, Theses, and Masters Projects
The value of habitats in terms of biological production is of interest to ecologists and resource managers. Seagrasses are a commonly occurring habitat type in shallow marine waters and have been shown to support high abundances of fish and invertebrates. In lower Chesapeake Bay, seagrasses grow in a shallow fringe in the subtidal zone. Although, ample evidence exists for the value of these habitats as foraging and rearing areas for a variety of organisms, the connectivity among species and the benefits derived from these habitats in terms of production have not been well described, especially for small, seasonally occurring finfishes. …
The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley
The Roles Of Dispersal And Predation In Determining The Seedling Recruitment Patterns Of A Zostera Marina System, Stephen R. Manley
Dissertations, Theses, and Masters Projects
Seed dispersal and seed predation are two important processes in the early life history of plants. The interaction between these two processes influences the population recruitment from a parent plant. These mechanisms have been studied extensively in terrestrial plants and have resulted in various models to describe plant recruitment (e.g. Janzen-Connell, Hubbell, McCanny). However, seed dispersal and predation may also influence the population recruitment of marine angiosperms, such as Zostera marina (eelgrass). The objectives of this study were to determine: 1.) the patterns of seed dispersal as a function of distance from the seed source, 2.) the predation pressure on …
An Evaluation Of A Reduced Bar Spacing Turtle Excluder Device In The U.S Gulf Of Mexico Offshore Shrimp Trawl Fishery, Michel Anthony Nalovic
An Evaluation Of A Reduced Bar Spacing Turtle Excluder Device In The U.S Gulf Of Mexico Offshore Shrimp Trawl Fishery, Michel Anthony Nalovic
Dissertations, Theses, and Masters Projects
Shrimp are the most economically valuable internationally-traded seafood commodity, and wild-caught, trawled shrimp make up almost half of the ~6.6 million metric tons of annual global production. Shrimp trawling is responsible for one-third of the world’s total fisheries bycatch, leading many to consider shrimp trawling to be the single most destructive fishing practice in the world. Though the bycatch of large marine animals can be significantly reduced by use of turtle excluder devices (TEDs) on shrimp trawls, current TED designs are ineffective at reducing the capture of smaller organisms which represent a large portion of the total bycatch. To further …
Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber
Long-Term Change In Copepod Community Structure In The Western Antarctic Peninsula: Linkage To Climate And Implications For Carbon Cycling, Miram Rayzel Gleiber
Dissertations, Theses, and Masters Projects
Copepods are the dominant mesozooplankton in the Southern Ocean, but long- term change in their abundance and distribution along the Western Antarctic Peninsula (WAP), a region experiencing rapid climate warming, is unknown. Copepods are also potentially important grazers of phytoplankton in the WAP and contributors to carbon export through production of sinking fecal pellets. I examined summer (January- February) copepod community structure and abundance along the WAP over two decades (1993-2013) and investigated long-term trends in copepod abundance and their relationship with environmental parameters (sea ice, phytoplankton biomass and productivity, climate indices, and sea surface temperature). Copepods comprised on average …
High-Resolution Sediment Records Of Seismicity And Seasonal Sedimentation From Prince William Sound, Alaska, Using Xrf Core Scanning, Eric J. Miller
High-Resolution Sediment Records Of Seismicity And Seasonal Sedimentation From Prince William Sound, Alaska, Using Xrf Core Scanning, Eric J. Miller
Dissertations, Theses, and Masters Projects
The southern coast of Alaska is a climatically sensitive and tectonically active region, however due to its remoteness and harsh climate there are limited long-term historical records of environmental conditions such as storm frequency, river discharge, and earthquakes. In order to determine the potential for Prince William Sound sediments to contain high-resolution paleorecords of these conditions, a suite of 11 gravity cores was collected within the Sound in order to determine the modern day sediment depositional trends and to develop elemental proxies for earthquakes and seasonal sedimentation. 210Pb/137Cs-derived sedimentation rates and grain size trends indicate that there are two distinct …
Sediment Deposition And Reworking: A Modeling Study Using Isotopically Tagged Sediment Classes, Justin J. Birchler
Sediment Deposition And Reworking: A Modeling Study Using Isotopically Tagged Sediment Classes, Justin J. Birchler
Dissertations, Theses, and Masters Projects
A sediment transport model within the Regional Ocean Modeling System (ROMS) was used to examine how repeated cycles of deposition, erosion, and bioturbation influence flood and storm event bed character offshore of a significant fluvial source. Short-lived radioisotopes Beryllium-7 (7Be) and Thorium-234 (234Th) can be used as tracers of deposition and reworking on the continental shelf, and modeled profiles of these radioisotopes, along with simulated profiles of sediment bed grain size distributions, were analyzed for various model runs.The presence of an atmospherically derived radionuclide,7Be, in seafloor sedimentindicates terrestrial (riverine derived) sediment deposition offshore of a fluvial source.In contrast,234Th naturally occurs …
Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter
Effects Of Saltwater Intrusion On Vegetation Dynamics And Nutrient Pools In Low-Salinity Tidal Marshes, Pamunkey River (Virginia, Usa), Lori A. Sutter
Dissertations, Theses, and Masters Projects
This study investigated vegetation changes in a former tidal freshwater marsh (TFM) to determine the role that salinity intrusion plays in vegetation dynamics. Field observations along a narrow salinity gradient in the Pamunkey River revealed that vegetation is shifting to fewer dominants with increasing salinity. Two remaining dominants, Peltandra virginica and Zizania aquatica (hereafter Peltandra and Zizania, respectively), had variable net CO2 assimilation throughout the growing season. Peltandra net CO2 assimilation declined both over the growing season and in marshes with higher salinity; whereas, Zizania generally increased over the growing season peaking in late summer. The same species' tissue nutrients …
Studies Of Mortality Estimation, Amy Y. Then
Studies Of Mortality Estimation, Amy Y. Then
Dissertations, Theses, and Masters Projects
Instantaneous total mortality rate Z can be partitioned into two components: fishing, F, and natural mortality, M. A number of data-poor methods have been developed to estimate Z, F, and M, and these methods tend to rely on fairly restrictive assumptions as well as on data types that are easy to obtain, e.g., length or other life history information. The overarching goal of this dissertation is to contribute to the advancement of methods for estimating these important and influential stock parameters. The relevant issues and the gaps in knowledge pertaining to these data-poor methods are outlined in the Introduction chapter …
Quantification Of Nursery Habitats For Blue Crabs In Chesapeake Bay, Gina M. Ralph
Quantification Of Nursery Habitats For Blue Crabs In Chesapeake Bay, Gina M. Ralph
Dissertations, Theses, and Masters Projects
The blue crab is an iconic species in Chesapeake Bay, supporting important commercial and recreational fisheries and functioning as a critical link in the food web. Structurally complex habitats are often cited as nurseries for the blue crab, and other commercially important fish and crustacean species, by providing enhanced growth and survival for juveniles. I quantified the value of shallow habitats as nurseries for blue crabs through field studies and a demographic model. In Chapter 2, I utilized a two-year juvenile survey in vegetated habitats of the lower Bay to examine the effect of habitat complexity on the density of …
Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys
Factors Influencing Year-Class Strength And Growth Of Young-Of-The-Year Summer Flounder (Paralichthyidae: Paralichthys Dentatus), Lauren N. Nys
Dissertations, Theses, and Masters Projects
No abstract provided.
Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell
Anthropogenic Modifications Of Connectivity At The Aquatic-Terrestrial Ecotone In The Chesapeake Bay, Robert Earl Isdell
Dissertations, Theses, and Masters Projects
No abstract provided.
Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker
Physiological Stress And Post-Release Mortality Of White Marlin (Kajikia Albida) Caught In The U.S Recreational Fishery, Lela Sylvia Schlenker
Dissertations, Theses, and Masters Projects
White Marlin (Kajikia albida) is a highly migratory species that occurs throughout temperate and tropical regions of the Atlantic Ocean and is the basis of a large sport fishery along the United States Atlantic coast. The single, Atlantic-wide stock is considered to be overfished, with less than one-third the spawning biomass estimated to be necessary for maximum sustainable yield. Billfish management measures adopted by the International Commission for the Conservation of Atlantic Tunas (ICCAT) and implemented in the U.S. by the National Marine Fisheries Service (NMFS), as well as increasing angler awareness of conservation, have resulted in the vast majority …
Development Of A Large-Scale Storm Surge And High-Resolution Sub-Grid Inundation Model For Coastal Flooding Applications: A Case Study During Hurricane Sandy, Jon Derek Loftis
Development Of A Large-Scale Storm Surge And High-Resolution Sub-Grid Inundation Model For Coastal Flooding Applications: A Case Study During Hurricane Sandy, Jon Derek Loftis
Dissertations, Theses, and Masters Projects
Coastal inundation initiated via storm surge by hurricanes and nor'easters along the U.S. East Coast is a substantial threat to residential properties, community infrastructure, and human life. During and after the storm, compounding with heavy precipitation and upland drainage, inundation can be caused by the combination of storm surge and river-induced inland flooding in various locations throughout the coastal plain. Thus, coastal inundation can be expanded from the open coast upstream into the tributaries of the New York Bay including the Hudson and East River systems. Given the cross-disciplinary nature of the dynamics (encompassing hydraulics, oceanography, and hydrology), and the …