374 research outputs found

    The American Garden at Powderham: Delightful Retreat in the Plantation

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    This thesis explores the history of the American Garden at Powderham in Devon, England. The seven-acre space was created, abandoned, and replanted over the course of over two-hundred years yet manages to convey remarkable integrity and sense of place. In the process of discovering who created the garden, this study aims to bring a deeper understanding of how and why American gardens, and Powderham’s in particular, were constructed in the late Georgian period. Because the Powderham American Garden has changed significantly over the past 200 years, the garden is not as it appeared in the late eighteenth and early nineteenth centuries. Developing a site analysis based on historic maps, household invoices and inventories, correspondence, diaries and accounts of family members and visitors, artwork, books at Powderham, and treatises of contemporary horticulturists generates context for understanding the garden’s likely historic appearance and use. Other British eighteenth-century American gardens offer comparables for Powderham’s garden. This evolving contextualized understanding elucidates the garden’s meaning and leads to ideas about its interpretation and presentation to a visiting public today. The Georgian garden was designed for movement – meant to be experienced in motion and sequence. As the narration progresses through the garden, this paper will explore the structures, plants, views, spatial organization, and circulation in order to address the central question of this thesis: Who and what forces created the American Garden, and how does the garden convey a broader understanding of and relationship to culture and society in the late Georgian era

    A survey of the food habits and distribution of the fishes of Tuckahoe Creek, Virginia, with special emphasis on Lepomis macrochirus Rafinesque

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    An integral part of the ecological study of any organism is a good understanding of the food relationships. Basic studies of the distribution and ecology of common fresh-water fishes are necessary before a more detailed analysis can be made of the fishes in a particular area. Lagler (1956) states that food habit studies help determine population levels, rates of growth, and condition of the fishes. He also concludes that they serve as a partial basis for determining the status of various predatory and competing forms. Raney (1942) states that an intelligent fishery management program depends heavily upon information gained through food habit analyses. Many of the previous studies have been concerned with the quantity of food material consumed and the workers therefore, have often employed a volumetric analysis. The present study; however, is not concerne with volume of food but rather with the number of fishes with food and the number of organisms taken

    Some effects of Hurricane Agnes on water quality in the Patuxent River Estuary

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    A post-Agnes study that emphasized environmental factors was carried out on the Patuxent River estuary with weekly sampling at eight stations from 28 June t o 30 August 1972. Spatial and temporal changes in the distribution of many factors , e.g., salinity , dissolved oxygen, seston, particulate carbon and nitrogen, inorganic and organic fractions of dissolved nitrogen and phosphorus, and chlorophyll a were studied and compared t o extensive earlier records. Patterns shown by the present data were compared especially with a local heavy storm that occurred in the Patuxent drainage basin during July 1969. Estimates were made of the amounts of material contributed via upland drainage. A first approximation indicated that 14.8 x l0 (3) metric tons of seston were contributed t o the head of the estuary between 21 and 24 June. (PDF contains 46 pages

    Some effects of tropical storm Agnes on water quality in the Patuxent River estuary

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    A post Agnes study emphasizing environmental factors...weekly sampling at eight stations from 28 June to August 30, 1972. Spatial and temporal changes in the distribution of many factors, e.g., salinity, dissolved oxygen (DO), seston, particulate carbon and nitrogen, inorganic and organic fractions of dissolved nitrogen and phosphorus, and chlorophyll a were studied and compared to earlier extensive records. Patterns shown by the present data were compared especially with a local heavy storm that occurred in the Patuxent drainage basin during July 1963. Some interesting correlations were observed in the data. (PDF has 39 pages.

    The A Posteriori Aspects of Estuarine Modeling

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    This exercise is the application of an analytical method for systematically modeling ecosystems data to observations made on a naturally eutrophic, mesohaline planktonic microcosm. The theory and experimental design are briefly outlined and the particular steps in the acutal modeling process follow. Then there is a discussion as to how the whole endeavor can be refined to culminate in models with predictive capabilities. (PDF has 16 pages.

    Projections for measuring the size of the solar core with neutrino-electron scattering

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    We quantify the amount of data needed in order to measure the size and position of the 8^8B neutrino production region within the solar core, for experiments looking at elastic scattering between electrons and solar neutrinos. The directions of the electrons immediately after scattering are strongly correlated with the incident directions of the neutrinos, however this is degraded significantly by the subsequent scattering of these electrons in the detector medium. We generate distributions of such electrons for different neutrino production profiles, and use a maximum likelihood analysis to make projections for future experimental sensitivity. We find that with approximately 20 years worth of data the Super Kamiokande experiment could constrain the central radius of the shell in which 8^8B neutrinos are produced to be less than 0.22 of the total solar radius at 95% confidence.Comment: 5 pages, 2 figures. Matches version accepted to PRL. Improved 2D analysis and results discussio

    The Empirical Modeling of an Ecosystem

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    The authors have endeavored to create a verified a-posteriori model of a planktonic ecosystem. Verification of an empirically derived set of first-order, quadratic differential equations proved elusive due to the sensitivity of the model system to changes in initial conditions. Efforts to verify a similarly derived set of linear differential equations were more encouraging, yielding reasonable behavior for half of the ten ecosystem compartments modeled. The well-behaved species models gave indications as to the rate-controlling processes in the ecosystem

    A Synoptic View of a Coastal Plain Estuary.

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    During October, 1972 the Patuxent River Estuary was monitored intensively and synoptically over two tidal cycles to determine the spatial and temporal patterns of various hydrodynamic, chemical and biological features. Forty-one depths at eleven stations along nine transects were sampled simultaneously at hourly intervals for salinity, temperature, dissolved oxygen, chlorohyll a, particulate nitrogen, nitrate, nitrite, total kjeldahl nitrogen, ammonia, particulate carbohydrate, dissolved organic carbon, total hydrolizable phosphorous, dissolved inorganic phosphorous, suspended sediment, particle size distribution, and zooplankton. Tidal velocity was continuously monitored at each depth by recording current meters. Riverine input and meteorological conditions were relatively stable for two weeks preceeding the deployment. This communication describes the calculation of the intrinsic rates of change of the observed variables from their measured distributions in the Estuary. The steady-state, one-dimensional equation of species continuity is employed to separate the advection and tidal dispersion of a hydrodynamically passive substance frbm its intrinsic rate of change at point. A new spatial transform is introduced for the purpose of interpolation and extrapolation of data.The intrinsic rate of change profiles reveal a region of heavy bloom activity in the upper estuary and a secondary bloom near the point in the River that most of the suspended material settles out. The changes in ammonia and nitrates are highly correlated to the productivity patterns. Phosphorous rates are less closely correlated to productivity. The perturbations that the Chalk Point steam electric power plant have on the heat and oxygen balances are easily discernible

    How Should Research And Monitoring Be Integrated?

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    Scientific knowledge of Chesapeake Bay and tidal tributaries has accumulated over many years beginning mostly with descriptive surveys prior to the 1960\u27s and 1970\u27s and evolving towards a coupling of monitoring and research in recent years. This essay discusses the need to more fully couple monitoring and research efforts in the Bay system because such a union of efforts is argued to be the most effective way to assess gross trends in the health of the system (monitoring) and to understand the basic forces causing these trends (research). We argue that together they provide part of the framework necessary for effective management of the living resources of the bay region.https://scholarworks.wm.edu/vimsbooks/1176/thumbnail.jp

    Marine Metagenomics: New Tools for the Study and Exploitation of Marine Microbial Metabolism

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    The marine environment is extremely diverse, with huge variations in pressure and temperature. Nevertheless, life, especially microbial life, thrives throughout the marine biosphere and microbes have adapted to all the divergent environments present. Large scale DNA sequence based approaches have recently been used to investigate the marine environment and these studies have revealed that the oceans harbor unprecedented microbial diversity. Novel gene families with representatives only within such metagenomic datasets represent a large proportion of the ocean metagenome. The presence of so many new gene families from these uncultured and highly diverse microbial populations represents a challenge for the understanding of and exploitation of the biology and biochemistry of the ocean environment. The application of new metagenomic and single cell genomics tools offers new ways to explore the complete metabolic diversity of the marine biome
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