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Evaluation Of Survival And Recovery Characteristics Of Bifidobacteria As Indicators Of Fecal Pollution Of Water, John Elmer Ravenscroft Jr.
Evaluation Of Survival And Recovery Characteristics Of Bifidobacteria As Indicators Of Fecal Pollution Of Water, John Elmer Ravenscroft Jr.
Graduate Theses, Dissertations, and Problem Reports
The examination of aquatic environments for bacterial indicator organisms has proven to be a useful and well-established practice for the purpose of monitoring microbiological water quality. An ideal indicator of fecal pollution should be present in sufficient density to allow detection, present simultaneous with pathogen(s), incapable of aftergrowth in external aquatic environments, easy to enumerate, and exclusively of fecal origin. Unfortunately, none of the indicator organisms presently in use today meet all of these requirements. Bifidobacteria show promise as indicators of fecal pollution in water with the additional ability of potentially distinguishing between fecal pollution of human and animal origin. …
Effects Of Plant Flavonoids On The Fate Of Polynuclear Aromatic Hydrocarbons In Rhizosphere Soil, Xiujin Qui
Effects Of Plant Flavonoids On The Fate Of Polynuclear Aromatic Hydrocarbons In Rhizosphere Soil, Xiujin Qui
Graduate Theses, Dissertations, and Problem Reports
High-molecular-weight polynuclear aromatic hydrocarbons (PAHs) are persistent in the environment although a wide variety of microorganisms can metabolize PAHs. In the past decades, laboratory and filed studies have shown that PAH degradation in soil is often limited by poor bioavailability and oxygen availability. Bound residue formation of PAHs with macromolecules of soil organic matter is an important fate mechanism. More recently, phytoremediation for PAH-contaminated soils is being explored. It is believed that PAH degradation may be enhanced in rhizosphere soil due to the improved aeration condition and the active soil microbial community sustained by root exudates. Whether certain root exudates …
Agricultural Non-Point Source (Agnps) Water Quality Modeling In A Gis Environment, Stephen George Carpenter
Agricultural Non-Point Source (Agnps) Water Quality Modeling In A Gis Environment, Stephen George Carpenter
Graduate Theses, Dissertations, and Problem Reports
This thesis project outlines the development and implementation of a complex GIS project in a government agency. The objective of the project was to integrate a public domain GIS package (GRASS) with a commercial structured query language database in order to undertake Agricultural Non-Point Source (AGNPS) water quality modeling. Three general areas of GIS technology were investigated consisting of technical issues involved in linking GIS; the model; database development; and a discussion of system performance from an institutional perspective.
Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers
Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers
Graduate Theses, Dissertations, and Problem Reports
Concern over scale is not new, and it is not restricted to geographers. Spatial and temporal scaling is a conceptual and methodological problem for all sciences using geographic information. This paper teases out issues of scale and ecological fallacy from the literature and discusses how these issues influence the applicability of an influential theoretical framework in stream ecology, the River Continuum Concept (RCC). Investigators are faced with decisions regarding scale during sampling location selection, field data capture, and subsequent data interpretation. A thorough understanding of the heterogeneity of stream habitats and the life histories of the organisms being studied could …
Sedimentology Of Historic And Prehistoric Deposits In The Drainage Basin Of Deep River And Muddy Creek On The Piedmont Of North Carolina, Victoria Leanne Spurgeon
Sedimentology Of Historic And Prehistoric Deposits In The Drainage Basin Of Deep River And Muddy Creek On The Piedmont Of North Carolina, Victoria Leanne Spurgeon
Graduate Theses, Dissertations, and Problem Reports
Deep River and Muddy Creek flow across a granitic and volcanic terrain intruded by diabase dikes in the Piedmont physiographic province of central North Carolina. Geoarchaeological and sedimentological investigation of these Piedmont streams included fourteen trenches dug at four floodplain localities. Soils in these trenches were described using standard soil taxonomy and sampled for particle-size, magnetic susceptibility, and mineralogical analyses.;Increased upland erosion rates, after European settlement, left more than a meter of historic sediments in some areas of the floodplains. A paleosol, indicated by an Ab horizon, records the floodplain surface at the time of European contact. This paleosol, dated …
Inventory And Prediction Of Heavy-Duty Diesel Vehicle Emissions, Justin Michael Kern
Inventory And Prediction Of Heavy-Duty Diesel Vehicle Emissions, Justin Michael Kern
Graduate Theses, Dissertations, and Problem Reports
A vehicle emissions inventory is an account of emissions produced by all vehicles in an area. Many different factors can affect the emissions and the measurement of the emissions that are used to create an emissions inventory. These factors for heavy-duty diesel vehicles have been addressed and their relative affect on emissions was evaluated from test data and analytical analyses. These elements can affect the emissions by a factor of 15 depending on testing conditions.;One purpose that an emissions database serves is to provide a source for predicting future emissions for a specific vehicle or many vehicles in a general …
Iron And Acid Removal From Acid Mine Drainage In Open Limestone Systems, Qingyun Sun
Iron And Acid Removal From Acid Mine Drainage In Open Limestone Systems, Qingyun Sun
Graduate Theses, Dissertations, and Problem Reports
Passive systems, like wetlands, anoxic limestone drains, and open limestone channels, show promise for treating acid mine drainage (AMD) discharges. Open limestone channels have been developed for over ten years and the treatment effectiveness of AMD by open limestone systems shows wide variation. The variation is due to site conditions (slope and size of the limestone channel) but more importantly to the surface area of the limestone and iron concentrations in the water. Iron in AMD coats the limestone in open limestone systems thereby reducing the surface area available for reaction. Over time, the limestone appears to lose its ability …
Heavy Metal Redistribution In Soils Using Compost As A Soil Amendment, Jason Thomas Morrison
Heavy Metal Redistribution In Soils Using Compost As A Soil Amendment, Jason Thomas Morrison
Graduate Theses, Dissertations, and Problem Reports
Organic soil amendments such as compost can reduce the availability of heavy metal contaminated soil. The objectives of this study were (1) to evaluate the efficiency of compost as an soil amendment within heavy metal contaminated soil; (2) to determine the hypoaccumulation of heavy metals in the stem, shoot, and root systems of white clover and wheat; (3) to identify movement of heavy metals within the soil; (4) to evaluate the differences of nodule formation in Trifolim repens. Three volumes of compost were added to a heavy metal contaminated soil (additions of zero, 10, and 40 percent compost, by volume). …