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Showing 1 to 19 of 19 for “"Lower Chesapeake Bay"”.
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Microzooplankton Dynamics in Lower Chesapeake Bay and Its Major Tributaries
… and biomass at 14 stations located within Chesapeake Bay and four rivers. Microzooplankton are defined as those heterotrophic organisms which range from 20 to 200 $\mu$m in size, and in this study were mainly composed of copepod nauplii, rotifers, and ciliates. Ciliates were the most …
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Surface Circulation and Horizontal Diffusion Processes of the Lower Chesapeake Bay
… and horizontal diffusion processes of the lower Chesapeake Bay. The study area encompasses some 160 km<sup>2</sup> and includes the area north of Thimble Shoal Channel, southwest of Chesapeake Channel and west of the Chesapeake Bay Bridge and Tunnel. Eleven trials utilizing buoyed drogues …
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Geomorphology and Dynamics of a Sand Wave in Lower Chesapeake Bay, Virginia
… in a sand wave field recently discovered in the lower Chesapeake Bay, Virginia, was studied intensively for morphology, sedimentology and in terms of dynamic processes. The morphologic investigation consisted of bathymetric surveys of the sand wave field and the specific sand wave. Twenty-five …
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Provenance of Sands Within the Lower Chesapeake Bay Based on Ilmenite Composition
<p>Surficial sands deposited in the Chesapeake Bay are a mixture of sands derived from the bay's shorelines, from offshore, and from relict deposits. Direct fluvial input is probably minor except from the James River, which may serve as a local source of sands in the Thimble Shoals area. Sands in …
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Benthic and Planktonic Microalgal Community Structure and Primary Productivity in Lower Chesapeake Bay
… in marine and estuarine systems. In Chesapeake Bay, microalgae facilitate the survival and development of ecologically and economically relevant fauna, including shellfish and finfish populations. While regarded as significant components of coastal environments, microphytobenthic …
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Controls on the Formation of Algal Blooms in the Lower Chesapeake Bay and Its Tributaries
<p>Algal blooms occur seasonally in the Chesapeake Bay and its tributaries, and while the consequences of algal blooms have been qualitatively and quantitatively assessed, the causes of algal blooms and mechanisms of bloom initiation are still not well understood despite decades of research. In …
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Seasonal and Diel Patterns of Abundance and Productivity of Phototrophic Picoplankton in the Lower Chesapeake Bay
… (0.2 to 2.0 μm) dynamics within the lower Chesapeake Bay. A 15 month study of phototrophic picoplankton abundance and productivity was made from June 1988 to October 1989. Annual picoplankton abundance using epifluorescence microscopy ranged from 7.26 x 10<sup>6</sup> cells/1 in the …
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The Temporal and Spatial Distribution of Hydrocarbons in Atmospheric Deposition From Stations Surrounding Lower Chesapeake Bay
… from urban and non-urban locations surrounding lower Chesapeake Bay. Mean hydrocarbon concentrations in bulk deposition samples were over three times greater at the urban station indicating a localized source. The major hydrocarbons present were n-alkanes, polycyclic aromatic hydrocarbons (PAH), …
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On the life history, systematics and ecology of Ruppia maritima L. (Potamogetonaceae) in lower Chesapeake Bay
… inhabitant of shallow water habitats. In Chesapeake Bay, Ruppia maritima L. (Potamogetonaceae) and Zostera marina L. (Zosteraceae) form an important submerged aquatic vegetation community. Research in Chesapeake Bay has focused primarily on Zostera marina. Ruppia maritima occurs abundantly …
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A Comparison of Recruitment Strategies Among Brachyuran Crustacean Megalopae of the York River, Lower Chesapeake Bay and Adjacent Shelf Waters
… a transect of the Pamunkey River, York River, lower Chesapeake Bay and adjacent coastal waters were sampled from July through September 1980. The megalopa stages of 11 brachyuran species were sampled. Vertical and horizontal distributions are described for each species in relation to salinity …
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Distribution of Free Marine Viruses of Lower Chesapeake Bay and Their Effects on Life-History Parameters of the Estuarine Copepod <i>Acartia tonsa</i> Dana
… virus-like particles (VLPs) and bacteria in the lower Chesapeake Bay, vertical profiles of VLPs and bacteria were determined through the water column and 15-25 cm into the sediment at five stations. VLPs were about ten times more abundant in sediment pore water (3.7 x 10<sup>8</sup> VLPs …
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CHARACTERIZATION OF MICROSATELLITE LOCI AND PILOT POPULATION GENETIC ANALYSIS IN HICKORY SHAD, ALOSA MEDIOCRIS
… and population structure in tributaries of lower Chesapeake Bay, Virginia including James River and its tributaries (Appomattox and Chickahominy Rivers), Rappahannock River, and Pamunkey River. Genetic variation was extremely low. Estimates of observed heterozygosity were lower than expected …
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Continuously Stratified Flow Dynamics Over a Hollow
… and density profiles were measured over three lower Chesapeake Bay bathymetric depressions (hollows) in order to determine the effects of a hollow on a continuously stratified flow. Measurements showed an acceleration of the near-bottom flow as it moved toward the deepest part of the hollows, …
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Development and Standardization of a Short-Term Assay for Evaluating Polluted Estuarine and Coastal Environments: The Medaka Embryo-Larval Assay
… of this assay in field studies, surveys of lower Chesapeake Bay tributary water and sediment samples were performed using the MELA approach.</p> <p>The results indicate that the proposed assay is very useful for the evaluation of the developmental effects of individual toxicants as well as …
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Submarine Groundwater Discharge in the Southern Chesapeake Bay: Constraints From Numerical Models
… in geochemical and hydrologic budgets for the lower Chesapeake Bay, three coastal Virginia transects (southern Eastern Shore, Lafayette River, and Ocean View beach) with different topographic gradients were modeled using similar boundary conditions and consistent treatment of hydrogeologic …
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Plastics and Microplastics as Vectors for Bacteria and Human Pathogens
… experiments were set up in a tributary of the lower Chesapeake Bay to follow <em>Vibrio spp</em>. colonization and total bacterial community composition over time. Microplastics and paired seawater samples were also collected and examined for the presence and abundance of <em>Vibrio spp</em>. …
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Tidal Circulation in Chesapeake Bay
… examination of the tidal circulation of Chesapeake Bay and its major tributaries. Tide and current data, which were observed in Chesapeake Bay by the National Ocean Service during the period from 1972 to 1983, are analyzed and used to construct charts that describe the tide and tidal …
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The Aquatic Geochemistry of the Particle-Reactive Radionuclides PO-210, PB-210, and BE-7
… 1982 through October 1983 at two sites in lower Chesapeake Bay. Atmospheric deposition fluxes for Be-7 in wet-only and bulk precipitation averaged 0.013 and 0.014 pCi/cm<sup>2</sup>/d, respectively, and for Pb-210 averaged 0.36 and 0.40 pCi/cm<sup>2</sup>/yr, respectively, suggesting that …
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The Biogeochemistry of Iodine in Seawater
… samples were collected in the middle and lower Chesapeake Bay in different seasons between 1990 and 1992. The concentrations of iodate, iodide, and total iodine were determined by polarography or voltammetry. In the surface water iodate was the dominant form of inorganic iodine in the …