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Full-Text Articles in Marine Biology
Anthropogenic Causes Of Copepod Mortality And Bacterial Decomposition Of Copepod Carcasses, Samantha L. Bickel
Anthropogenic Causes Of Copepod Mortality And Bacterial Decomposition Of Copepod Carcasses, Samantha L. Bickel
Dissertations, Theses, and Masters Projects
Although zooplankton carcasses can be quite prevalent within aquatic systems, they have largely been overlooked in most zooplankton population studies. Anthropogenic stressors can potentially increase the overall abundance of carcasses on a local scale. Once a carcass is present within a system, the fate of its biomass is of considerable interest as it may be remineralized within the water column or transported to depth. Through the collection of field samples I assessed the possibility of an anthropogenic stressor (boat-generated turbulence) as a potential source of nonconsumptive mortality. I also conducted a series of laboratory experiments to monitor the decomposition of …
A Numerical Modeling Study On Barotropic And Baroclinic Responses Of The Chesapeake Bay To Hurricane Events, Kyoung-Ho Cho
A Numerical Modeling Study On Barotropic And Baroclinic Responses Of The Chesapeake Bay To Hurricane Events, Kyoung-Ho Cho
Dissertations, Theses, and Masters Projects
The barotropic and baroclinic responses of the Chesapeake Bay to forcings from two hurricanes were investigated by using unstructured-grid three-dimensional hydrodynamic models. The model domain includes Chesapeake Bay proper, the tributaries, and its extended continental shelf in the mid-Atlantic Bight. Two hurricanes were studied: Hurricane Floyd of September, 1999 and Hurricane Isabel of September, 2003, both of which made landfall within 100 km of the Chesapeake Bay mouth. Hurricane Floyd in 1999 passed through the entrance of the Bay from southwest to northeast along the coastlines of Virginia as a Category 1 storm, whereas Hurricane Isabel in 2003 made landfall …
Cultural Eutrophication And The Clam Macoma Balthica: Evidence For Trophic Disruption And Effects On Blue Crabs, Bryce J. Brylawski
Cultural Eutrophication And The Clam Macoma Balthica: Evidence For Trophic Disruption And Effects On Blue Crabs, Bryce J. Brylawski
Dissertations, Theses, and Masters Projects
Cultural eutrophication (CE) is the allochthonous input introduction of a quantity of matter, such as sediments, organic material, or nutrients, into a water body over the pre-anthropogenic (natural) levels. In most coastal estuaries CE has come to refer primarily to an increase in the concentration of phyto-nutrients. CE has been identified as the cause of very graphic phenomena such as hypoxia and fish kills. In this work I examine the potential for CE to alter the composition of the primary producer community and potentially alter or disrupt the benthic food web, using Macoma balthica as an indicator species. A series …
Assessing Genetic Variation Within And Among Native Populations And Hatchery Stocks Of Crassostrea Ariakensis Using Microsatellite Markers, Jie Xiao
Dissertations, Theses, and Masters Projects
Assessing genetic variation within and among native populations and hatchery stocks of Crassostrea ariakensis using microsatellite markers In response to the dramatic decline of eastern oyster (Crassostrea virginica) populations in the Chesapeake Bay, introduction of the non-native Asian oyster Crassostrea ariakensis has been proposed. Currently several hatchery stocks of C. ariakensis, derived from a few wild populations along the coast of Japan and China, are being maintained in U.S. hatcheries in the Pacific northwest and on the east coast. In recent years, as the risks of the proposed introduction are being assessed, these hatchery animals have been widely used for …
Multi-System Analysis Of Nitrogen Use By Phytoplankton And Heterotrophic Bacteria, Paul B. Bradley
Multi-System Analysis Of Nitrogen Use By Phytoplankton And Heterotrophic Bacteria, Paul B. Bradley
Dissertations, Theses, and Masters Projects
Traditional measurements of phytoplankton N uptake have been confounded by bacterial retention on filters used in 15N uptake studies, and such methodological obstacles have limited our understanding of phytoplankton-bacterial interactions regarding N cycling. In this research, uptake of various inorganic and organic N substrates by phytoplankton and bacteria was measured in several marine ecosystems using two distinct approaches: size fractionation into phytoplankton and bacterial size classes, and flow cytometric (FCM) sorting of autotrophic cells. Comprehensive assessments of N uptake dynamics were conducted in Chesapeake Bay, the Mid-Atlantic Bight, and Raunefjord, Norway, with supplementary data collected from the York River, Virginia …
Hydrography And Phytoplankton Distribution In The Amundsen And Ross Seas, Glaucia M. Fragoso
Hydrography And Phytoplankton Distribution In The Amundsen And Ross Seas, Glaucia M. Fragoso
Dissertations, Theses, and Masters Projects
The phytoplankton of the Ross Sea have been intensively studied during the last decade, as opposed to the Amundsen Sea, where virtually nothing is known about phytoplankton taxonomy and distribution. Blooms in the Ross Sea are usually composed of diatoms and the prymnesiophyte Phaeocystis antarctica; diatoms are often dominant in strongly stratified waters during the summer, whereas P. antarctica usually dominates in less stratified waters in the south-central polynya during spring. This study focused on understanding the environmental variables that influence the spatial patterns of phytoplankton assemblages during late summer and early fall, 2007, and late spring and early summer, …
Investigating The Relationships Between Recruitment Indices And Estimates Of Adult Abundance For Striped Bass, Weakfish, And Atlantic Croaker, Justine R. Woodward
Investigating The Relationships Between Recruitment Indices And Estimates Of Adult Abundance For Striped Bass, Weakfish, And Atlantic Croaker, Justine R. Woodward
Dissertations, Theses, and Masters Projects
Establishing the relationships between recruitment indices and estimates of adult abundance using fishery-independent data continues to remain one of the principal challenges faced by fisheries scientists due to the lack of concurrent monitoring programs designed to target different life stages of the same species. In Chesapeake Bay, however, multiple, fishery-independent surveys currently monitor the relative abundance of YOY and adult fishes. Using the available data from these surveys, the relationships between estimates of relative abundance for young-of-year and adults of striped bass (Morone saxatilis), weakfish (Cynoscion regalis), and Atlantic croaker (Micropogonias undulatus) were examined. Year-class strength was reflected in subsequent …
Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera
Egg Capsule Hatching Success In Rapana Venosa And Urosalpinx Cinerea In Relation To Temperature And Salinity, Stephanie M. Gera
Dissertations, Theses, and Masters Projects
The maintenance of a population within the geographic range is influenced by the physical and environmental conditions under which breeding occurs. It is hypothesized that environmental conditions under which egg capsules are successfully hatched will influence the range of potential habitat of the invasive veined rapa whelk, Rapana venosa, and the native Atlantic oyster drill, Urosalpinx cinerea, in the Chesapeake Bay. This study examines the environmental conditions of temperature, salinity, and the time of deposition of egg capsules within the reproductive period (here quantified as cumulative number of day degrees at egg capsule deposition). The range of R. venosa and …
Function Of Seed-Bank Ecology In Mid-Atlantic Semi-Annual And Perennial Zostera Marina Beds, Jessie C. Jarvis
Function Of Seed-Bank Ecology In Mid-Atlantic Semi-Annual And Perennial Zostera Marina Beds, Jessie C. Jarvis
Dissertations, Theses, and Masters Projects
The effects of water quality and sediment composition on mid-Atlantic semi-annual and perennial Zostera marina reproductive success, seed-bank viability, and seed germination were elucidated using laboratory and in situ experiments, quantitative field observations, and ecological model simulations. The sediment seed-bank was found to play a large role in the recovery of perennial Z. marina beds in the Chesapeake Bay and in the yearly re-establishment of beds in North Carolina which were determined to have a semi-annual life history. However, the resiliency provided by sediment seed-bank for both semi-annual and perennial Z. marina beds was limited as seeds remained viable for …