2 resultados para Niembsch von Strehlenau, Nikolaus, 1802-1850.

em DRUM (Digital Repository at the University of Maryland)


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A model to estimate the mean monthly growth of Crassostrea virginica oysters in Chesapeake Bay was developed. This model is based on the classic von Bertalanffy growth function, however the growth constant is changed every monthly timestep in response to short term changes in temperature and salinity. Using a dynamically varying growth constant allows the model to capture seasonal oscillations in growth, and growth responses to changing environmental conditions that previous applications of the von Bertalanffy model do not capture. This model is further expanded to include an estimation of Perkinsus marinus impacts on growth rates as well as estimations of ecosystem services provided by a restored oyster bar over time. The model was validated by comparing growth estimates from the model to oyster shell height observations from a variety of restoration sites in the upper Chesapeake Bay. Without using the P. marinus impact on growth, the model consistently overestimates mean oyster growth. However, when P. marinus effects are included in the model, the model estimates match the observed mean shell height closely for at least the first 3 years of growth. The estimates of ecosystem services suggested by this model imply that even with high levels of mortality on an oyster reef, the ecosystem services provided by that reef can still be maintained by growth for several years. Because larger oyster filter more water than smaller ones, larger oysters contribute more to the filtration and nutrient removal ecosystem services of the reef. Therefore a reef with an abundance of larger oysters will provide better filtration and nutrient removal. This implies that if an oyster restoration project is trying to improve water quality through oyster filtration, it is important to maintain the larger older oysters on the reef.

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The Maynard-Burgess House was excavated by Archaeology in Annapolis from Fall, 1990 to Summer, 1992. The still-standing house is located at 163 Duke of Gloucester Street in Annapolis' Historic District and is today being restored by Port of Annapolis, Incorporated. Archaeological testing and excavation of the site was developed alongside architectural analyses and archival research as the initial phase of the home's restoration. The Maynard-Burgess House was continuously occupied by two African-American families, the Maynards and the Burgesses, from the 1850s until the late 1980s. The main block of the house was built between 1850 and 1858 by the household of John T. Maynard, a free African American born in 1810,and his wife Maria Spencer Maynard. Maynard descendants lived in the home until it was foreclosed in 1908 and subsequently sold to the family of Willis and Mary Burgess in 1915. Willis had been a boarder in the home in 1880, and his sister Martha Ready had married John and Maria's son John Henry. Burgess descendants lived at the home until its sale in 1990.