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dc.contributor.authorTo, Yan Pui Samuelen_US
dc.date.accessioned2017-03-10T21:54:12Z
dc.date.available2017-03-10T21:54:12Z
dc.date.issued1974en_US
dc.identifier.urihttp://hdl.handle.net/10919/76458
dc.description.abstractThe purpose of this investigation was to determine the effect of sediments in the Occoquan Reservoir on the water quality. Phosphate determination by the ascorbic acid method was first evaluated for its precision and accuracy. An assay was developed to measure the rate of nutrient phosphate release to the overlying water in a quiescent dark condition. The assay was evaluated to test for its reliability in giving valid conclusions. The assay was an attempt to provide a system similar to the actual system which could be used in the laboratory. Also, the effect of different parameters could be studied by varying conditions one at a time. In this assay, it was found that the rate of release was not affected by normal pH changes, depth of sediment, or depth of overlying water. The rate of release was found to increase with increase in temperature, phosphate content in sediments, and reduced anaerobic condition. The rate was adversely affected by high concentration of salt, drying on sediment surface, thickness of physical barrier, and reduction of bacterial activities. Flushing seemed to decrease the rate of release by a constant ratio. Under normal conditions, sediments release other nutrients besides phosphates. However, it was found that whether the sediment served as a sink or source of phosphate was governed by the critical availability concentration which was different for different sediment. A study of the properties of the reservoir sediment showed that there were variations with respect to time, station, and depth, as well as vicinity within the same station, in this reservoir.en
dc.format.extentix, 101 leavesen_US
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_USen_US
dc.publisherVirginia Polytechnic Institute and State Universityen_US
dc.rightsThe authors of the theses and dissertations are the copyright owners. Virginia Techs Digital Library and Archives has their permission to store and provide access to these works.en_US
dc.subject.lccLD5655.V856 1974.T6en_US
dc.titleEffects of sediment on water quality in the Occoquan Reservoiren_US
dc.typeDissertationen_US
dc.contributor.departmentCivil Engineeringen_US
dc.description.degreePh. D.en_US
dc.identifier.oclc40145604en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineCivil Engineeringen_US
dc.type.dcmitypeTexten_US


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