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Modeling Phytoplankton Community Response To Nutrient Loading And Climate Change In A Shallow Temperate Estuary, Sara Aimee Blachman
Modeling Phytoplankton Community Response To Nutrient Loading And Climate Change In A Shallow Temperate Estuary, Sara Aimee Blachman
Dissertations, Theses, and Masters Projects
Phytoplankton account for at least half of all primary production in estuarine waters and are at the center of biogeochemical cycles and material budgets. Environmental managers use water column chlorophyll-a (chl-a) concentrations as a basic water quality indictor, as the problems of eutrophication and hypoxia are intrinsically linked to excessive phytoplankton growth. Evidence suggests that the distribution and frequency of harmful algal blooms may be increasing worldwide. For the most part, phytoplankton communities follow a standard seasonal pattern, with specific groups dominating the assemblage during the time of year when environmental conditions correspond to their requisites for growth. However, climate …
Zooplankton Community Composition And Grazing In The Amazon River Plume And Western Tropical North Atlantic Ocean, Brandon J. Conroy
Zooplankton Community Composition And Grazing In The Amazon River Plume And Western Tropical North Atlantic Ocean, Brandon J. Conroy
Dissertations, Theses, and Masters Projects
Large river plumes and frontal zones are important physical features influencing plankton distribution in the marine environment. In the western tropical North Atlantic Ocean (WTNA) the Amazon River plume may extend over an area reaching 1.5 x 106 km2. The freshwater plume creates a low-density lens in the surface 25m and supplies silicon and phosphorus to the WTNA. These physical and chemical gradients create an ideal environment for large-scale blooms of diatom diazotroph associations (DDAs), a symbiotic relationship between nitrogen-fixing cyanobacteria and chain-forming diatoms. While the physical and chemical properties of the plume with regard to influences on phytoplankton have …
Population Dynamics Of Gelatinous Zooplankton In The Chesapeake Bay And Sargasso Sea, And Effects On Carbon Export, Joshua Paul Stone
Population Dynamics Of Gelatinous Zooplankton In The Chesapeake Bay And Sargasso Sea, And Effects On Carbon Export, Joshua Paul Stone
Dissertations, Theses, and Masters Projects
Gelatinous zooplankton (GZ; cnidarians, ctenophores, and pelagic tunicates) periodically are the dominant members of the zooplankton throughout the majority of the world’s oceans. their unique body plans and life cycles allow them to rapidly take advantage of favorable environmental conditions, which has far-ranging consequences for food web dynamics and biogeochemical cycles. GZ populations have been speculated to respond to anthropogenic changes, but few long-term studies exist to test this hypothesis and even fewer have examined the consequent effects on carbon export. I analyzed two long-term time series in the Chesapeake Bay and one in the Sargasso Sea for annual and …
Modeling Flocculation And Deflocculation Processes Of Cohesive Sediments, Xiaoteng Shen
Modeling Flocculation And Deflocculation Processes Of Cohesive Sediments, Xiaoteng Shen
Dissertations, Theses, and Masters Projects
The transport and fate of cohesive sediments are responsible for many engineering, environmental, economic and policy issues that relate to, for example, siltation and dredging in navigation channels, water quality, water turbidity, pollutant transports, and biological ecosystem responses. Our current understanding, however, is insufficient to conduct accurate quantitative predictions of these processes. This is because the cohesive particles in natural waters will flocculate, which determines the settling, and thus the deposition behaviors. The simulation of flocculation processes is a primary challenge since the time variation of Floc Size Distribution (FSD) is controlled by a partial differential equation that also contains …
On Shelf-Slope Water Mass Exchanges Near Washington Canyon And Norfolk Canyon In The Mid-Atlantic Bight, Haixing Wang
On Shelf-Slope Water Mass Exchanges Near Washington Canyon And Norfolk Canyon In The Mid-Atlantic Bight, Haixing Wang
Dissertations, Theses, and Masters Projects
The physical exchanges between shelf and slope water masses are important drivers of biological productivity in the shelfbreak region of the Mid-Atlantic Bight (MAB). Based on two ocean glider surveys that were conducted in Autumn 2013, and concurrent wind and satellite based sea surface height observations, this study investigates the dynamic mechanisms of wind, surface height variation, water column hydrographic structure, and canyon topography in driving shelf-slope water mass exchanges across the shelfbreak near Norfolk Canyon and Washington Canyon in the MAB. Over the outer shelf, sea surface height variation and wind are important drivers of cross-shelfbreak transport through geostrophic …
Patterns Of Abundance And Community Dynamics In Atlantic Coastal Sharks, Cassidy Peterson
Patterns Of Abundance And Community Dynamics In Atlantic Coastal Sharks, Cassidy Peterson
Dissertations, Theses, and Masters Projects
No abstract provided.