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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Examining the influence of meteorological events on plankton dynamics in a coastal ecosystem (Lunenburg Bay, Canada)

Laurent, Arnaud 11 May 2011 (has links)
Pelagic ecosystems are inherently complex in coastal inlets where they are controlled by physical processes and influenced by biogeochemical and foodweb interactions. Meteorological events are important drivers of this ecological variability. This thesis investigates their effect on the plankton dynamics of Lunenburg Bay, an inlet on the Atlantic coast of Nova Scotia (Canada). In this region, meteorological events are dominated by upwelling in summer, which are a dominant source of flushing and nutrient variability for the inlets. Despite these events, which induce phytoplankton blooms in other regions, the concentration of phytoplankton as chlorophyll remains relatively low throughout the summer in Lunenburg Bay. To reveal the underlying processes limiting the development of phytoplankton biomass, and therefore to improve our understanding of the factors regulating plankton dynamics in this inlet, the objectives of this thesis are to determine the main drivers of variability in phytoplankton biomass and plankton community structure, and to identify the factors limiting the development of phytoplankton biomass in Lunenburg Bay. For that, I use a dataset collected at a coastal observatory located in Lunenburg Bay that covers the years 2003–2006, complemented by a series of transects carried out in summer 2006. The dataset covers physical, chemical and biological properties of the bay, including plankton taxonomy. Two types of physical-biological coupled models are developed: a low-resolution box model of Lunenburg Bay with steady-state wind forcing, and a high-resolution nested model of Lunenburg Bay using the Regional Ocean Modelling System (ROMS) to hindcast a series of upwelling events in 2006. The results reveal that four factors regulate the phytoplankton response to upwelling events in Lunenburg Bay, namely (1) the duration of an upwelling event, (2) the low nitrate concentration in source waters, (3) the flushing rate of the inlet (hence transport), and (4) the bathymetry along the inshore-offshore axis of the bay. In addition, (5) the occurrence of upwelling and (6) the inshore-offshore gradient of increasing depth influence the structure of respectively phytoplankton and zooplankton communities, indicating a dissimilarity in the processes structuring plankton communities in the lower food web. A conceptual model is then developed to describe the role of transport and nitrate concentration in source waters in controlling plankton dynamics in an inlet.
32

Currents, coasts and cays : a study of tidal upwelling and island wakes /

Coutis, Peter F. January 2000 (has links)
Thesis (Ph. D.)--University of New South Wales, 2000. / Also available online.
33

Structure and dynamics of the Pacific upper mantle /

Katzman, Rafael, January 1998 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1998. / "February 1998." "Doctoral dissertation." Includes bibliographical references (p. 189-198).
34

El Nino related variations in nutrient and chlorophyll distributions off Oregon /

Corwith, Holly L. January 2000 (has links)
Thesis (M.S.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 62-66). Also available online.
35

High-resolution sampling of particulate organic carbon in a coastal upwelling system /

Holser, Rachel R. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 38-41). Also available on the World Wide Web.
36

Measured and modeled particle export in equatorial and coastal upwelling regions /

Dunne, John P., January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (p. [156]-164).
37

A case study of a marine inversion on the Oregon coast

Garcia-Meitin, Rebecca Jo Manley, January 1975 (has links)
Thesis (M.S.)--Florida State University. / Vita. Includes bibliographical references (leaf 108).
38

Observations of the California Countercurrent

Harrod, Robert L. January 1984 (has links)
Thesis (M.S.)--Naval Postgraduate School, 1984. / Includes bibliographical references (p. 143-145).
39

Wind driven coastal upwelling in Lake Superior

Niebauer, H. J. January 1976 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [259]-264).
40

Coastal upwelling along the west coast of Vancouver Island

Jardine, Ian David January 1990 (has links)
Wind-driven up welling events near Brooks Peninsula off the west coast of Vancouver Island have been identified during the summers of 1988 and 1989 from sea surface NOAA AVHRR thermal imagery obtained at the UBC Satellite Oceanography and Meteorology Laboratory. Software has been developed to characterize the strength and extent of the surface cooling associated with the upwelling. A two-dimensional, 2-layer finite difference model with 1 km resolution has been formulated to examine the small-scale dynamics of the upwelling events. The model uses local wind and includes realistic coastline and bathymetry. The wind-stress and coastline configuration appear to be the main factors contributing to favourable upwelling regions. The results of the model compare favourably to the observed starting location of the upwelling. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

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