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Full-Text Articles in Life Sciences
Seasonal Nitrogen Uptake And Regeneration In The Water Column And Sea-Ice Of The Western Coastal Arctic, Steven E. Baer
Seasonal Nitrogen Uptake And Regeneration In The Water Column And Sea-Ice Of The Western Coastal Arctic, Steven E. Baer
Dissertations, Theses, and Masters Projects
The logistical difficulties of research in extremely low temperatures and lack of access to the Arctic have meant that there is a historic dearth of knowledge of coastal Arctic biogeochemistry, especially during winter when sea ice is present. Recent observations, however, indicate that the Arctic is changing rapidly. Changes include increased temperatures, decreased extent and volume of sea ice, and increased freshwater inputs. How these changes influence biogeochemical cycles is an open question, especially in the highly productive coastal regions of the Chukchi Sea. Here I present nitrogen (N) uptake and regeneration rates for phytoplankton and bacteria measured in the …
Foraging Ecology And Habitat Use Of The Northern Diamondback Terrapin (Malaclemys Terrapin Terrapin) In Southern Chesapeake Bay, Diane C. Tulipani
Foraging Ecology And Habitat Use Of The Northern Diamondback Terrapin (Malaclemys Terrapin Terrapin) In Southern Chesapeake Bay, Diane C. Tulipani
Dissertations, Theses, and Masters Projects
The northern diamondback terrapin (Malaclemys terrapin ) is the only estuarine turtle residing along western Atlantic and Gulf of Mexico coasts of North America. Through predation, terrapins may be a key species in coastal marine habitats by exerting top-down control on marsh invertebrates, and thereby help to maintain healthy marshes. Despite the terrapin's ecological importance, there has not been a thorough study of terrapin foraging ecology and movements in lower Chesapeake Bay. In this dissertation, the research focused on the foraging habits of diamondback terrapins and their effects within salt marsh and seagrass habitats of lower Chesapeake Bay. I provided …
Distribution And Impacts Of Invasive Bivalve Corbicula Fluminea In Tidal Freshwater York River Tributaries, Matthew Ryan Freedman
Distribution And Impacts Of Invasive Bivalve Corbicula Fluminea In Tidal Freshwater York River Tributaries, Matthew Ryan Freedman
Dissertations, Theses, and Masters Projects
The Asian clam, Corbicula fluminea, is one of the most invasive bivalves in the world but there is limited research on its presence in tidal freshwater systems. Despite its introduction into Chesapeake Bay tributaries in the 1970s, the initial colonization and subsequent development of populations of C. fluminea in the Mattaponi and Pamunkey sub-tributaries of the York River, Virginia, is mostly undocumented. This study assessed the spatial distribution and population structure of C. fluminea in tidal freshwater sections of these rivers (~45km) with benthic surveys during summer 2011 – 2012. Benthic grabs (2.4L, 0.023m2) taken at 40 sites in each …
Improvements In Triploid Crassostrea Virginica Production: Characterizing The Diploid Parent, Brian R. Callam
Improvements In Triploid Crassostrea Virginica Production: Characterizing The Diploid Parent, Brian R. Callam
Dissertations, Theses, and Masters Projects
The effect of triploidy to effect faster growth and increased survival compared to diploid oysters is called the ‘triploid advantage’ and this advantage in the Chesapeake Bay for Crassostrea virginica is the principal reason for the value of triploid C. virginica in the Chesapeake Bay, USA. The triploid advantage is hypothesized to be the result of genetic effects, physiological changes, or a combination of both. The causative genetic mechanisms at play may include additive genetic effects and heterosis while the physiological changes obtain from triploid sterility. The triploid advantage was examined by comparing 13 diploid and 13 triploid crosses across …