UMD Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/3

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a given thesis/dissertation in DRUM.

More information is available at Theses and Dissertations at University of Maryland Libraries.

Browse

Filters

2010 - 20112

Settings

Subject: search.filters.subject.estuarine turbidity maximum

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    PATTERNS IN DISTRIBUTION, GROWTH, AND TROPHODYNAMICS OF STRIPED BASS EARLY LIFE STAGES IN THE ESTUARINE TRANSITION REGION OF UPPER CHESAPEAKE BAY
    (2011) Shideler, Allison Rae Chandler; Houde, Edward D.; Marine-Estuarine-Environmental Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Variable production of young striped bass Morone saxatilis in the estuarine transition region depends on environmental and hydrographic conditions in the estuarine turbidity maximum (ETM) and salt front region of Chesapeake Bay. Spatio-temporal variability in occurrence, growth, and diet of early life stages of striped bass and zooplankton prey were compared in years of average (2007) and poor (2008) production of striped bass juveniles. Stable isotope analyses tracked sources of carbon and nitrogen in larval striped bass diets. The estuarine copepod Eurytemora affinis was the most important prey. It and the freshwater cladoceran Bosmina longirostris dominated diets of striped bass larvae. Bosmina was relatively important in 2007. Larvae grew faster in 2007 than in 2008 and growth was fastest within and up-estuary of the ETM and salt front. Stable isotope analysis indicated that carbon from both marine and terrestrial sources supports production of striped bass larvae.
  • Thumbnail Image
    Item
    Community Metabolism and Energy Transfer in the Chesapeake Bay Turbidity Maximum in 2007 and 2008
    (2010) Lee, Dong-Yoon; Hood, Raleigh R.; Marine-Estuarine-Environmental Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The estuarine turbidity maximum (ETM) is a zone of elevated organic matter concentrations and it is an important habitat for bacteria, zooplankton, and early-life-stages of fish. In an effort to identify the key mechanisms controlling production, we measured plankton community metabolism on a series of high-resolution spatial surveys in the upper Chesapeake Bay. The spatial patterns of metabolism revealed the highest primary production and community respiration rates downstream of the ETM region, and net heterotrophy in winter and spring. Also, strong correlations between plankton community metabolism and phytoplankton pigment concentrations, including chlorophyll-a and dinoflagellate indicating pigment peridinin, were observed. These correlations suggest that mixotrophic dinoflagellates were key organisms linking detrital and algal organic matter to higher trophic levels. It is hypothesized that the physiological advantages of mixotrophic dinoflagellates (i.e., autotrophic, heterotrophic) combined with the physical conditions in the ETM which enhance the quantity and quality of organic matter give rise to the high secondary production in the upper Chesapeake Bay.