Biology Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/2749

Browse

Filters

2005 - 20092

Settings

Subject: search.filters.subject.sea level rise

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    MARSH ELEVATION AND ACCRETION DYNAMICS ALONG ESTUARINE SALINITY GRADIENTS: OBSERVATIONAL AND EXPERIMENTAL STUDIES
    (2009) Beckett, Leah Hope-Menzies; Baldwin, Andrew H; Marine-Estuarine-Environmental Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Chesapeake Bay marshes are threatened by sea level rise and have experienced degradation as a result of saltwater intrusion and increased water levels. Rates of elevation and accretion change and vegetation communities may be affected by salt water intrusion and other processes as a result of sea level rise. An observational study of the Nanticoke River, a tributary to the Chesapeake Bay, utilizing surface elevation tables (SET) reflected that during the course of a two year study period, rates of marsh elevation change differed significantly along an estuarine salinity gradient. Surface elevation of oligohaline marshes decreased during the monitoring period and were significantly different from mesohaline marshes which increased in elevation. An experimental study in Patuxent River tidal freshwater marshes in which plots were irrigated with saltwater indicated that with saltwater intrusion vegetation communities may become less diverse.
  • Thumbnail Image
    Item
    The effect of sea level rise on seagrasses: Is sediment adjacent to retreating marshes suitable for seagrass growth?
    (2005-12-13) Wicks, Elinor Caroline; Koch, Evamaria W; Marine-Estuarine-Environmental Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Salt marsh retreat resulting from sea level rise creates new subtidal substrate (old marsh peat) for seagrasses, which is usually unvegetated. The hypothesis that sediment characteristics of old marsh peat are limiting to <em>Zostera marina</em> was tested in Chincoteague Bay, Maryland and in controlled experiments. A unique aspect of the study site is an eroding dune within the marsh that supplies sand to the subtidal. The organic content and sulfide concentrations of old marsh peat were not limiting <em>Z. marina</em> growth and seagrasses were able to colonize the old marsh peat if a layer of sand covered it. The lack of <em>Z. marina<em/> in old marsh peat may be due to a plant morphology that is highly susceptible to dislodgement. These findings suggest that seagrass distribution may be negatively affected by sea level rise as seagrasses may be unable to migrate shoreward due to unsuitable sediments adjacent to retreating marshes.