Identifying how the dominant runoff processes of sub-catchments integrate to determine hydrological responses at larger scales (> 1000 km2) remains a major challenge in hydrology. At these larger scales, major environmental differences such as climate, geology and land use may have increased influence on runoff dynamics. While process investigations at smaller scales (< 10km2) have been important in establishing the influence of topography and soils on runoff generation, more research at larger spatial scales is needed, since it is at such scales where important water management decisions are made in relation to applied problems such as floods and droughts. Tracers, such as stable isotopes of water, have proven utility as tools since they reflect the integration of processes at much smaller scales. In addition, geochemical tracers, such as alkalinity, help identify the geographical sources of runoff in larger catchments. This thesis focuses on their use to study catchment hydrological processes in the River Dee (~2,100 km2), NE Scotland, and to determine how these processes integrate at larger scales. Runoff from soil derived hydrological responsive pathways dominates during high flow facilitating a relatively rapid translation of precipitation isotope signatures into the channel network. Increased coverage of responsive soils resulted in reduced Mean Transit Time (MTT) estimates. High coverage of freely draining soils and certain landscape features often resulted in greater MTT estimates. Small scale heterogeneity appears to be averaged out at larger scales with MTTs indicating that the montane headwaters of the river are the dominant source of runoff. Transit Time Distributions (TTDs) suggest that catchment waters may have transit times of less than 2 weeks during high flows and greater than 10 years in summer baseflows.

Graduation date: 1980

Thesis (M.S.)--Ohio State University, 2006. / Includes bibliographical references (leaves 76-83). Available online via OhioLINK's ETD Center.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references. Also available in electronic version. Access restricted to campus users.

No description available.

No description available.

Detailed bacterial and chemical studies were conducted on Cardinal Creek, flowing through the Ball State University campus from May to December, 1972. Samples were collected from drain pipes flowing into the stream and also from the center of the stream between drain pipes.Results of the study show human waste materials are entering Cardinal Creek at the sampling site located behind the Ball State trailer courts. Forty-four percent of the time, ratios of fecal coliforms to fecal streptococci at this site were above 4.0 indicating human waste contamination.The presence of pathogens in the water is another clue to the quality of the surface water. Salmonella and Shigella are associated with gastro-intestinal diseases that may be spread by ingestion of water contaminated with these bacteria. Salmonella and Shigella were isolated on several occasions from the drain pipe behind the trailer courts. Salmonella paratyphi was found on the December 28 sampling date. It's presence in the creek shows human wastes are entering the stream.Chemical data, collected on December 28, indicate a heavy load of organic matter is entering Cardinal Creek at the Ball State trailer court drain pipe. Of all the sites sampled on this date, highest values for nitrogen and phosphorus and the lowest values for oxygen were found at the trailer court location.In conclusion, data collected in this study shows that water entering Cardinal Creek from the drain pipe located by the Ball State trailer courts, contains human fecal material. Measures should be taken to correct the situation.

No description available.

Thesis -- Departmental honors in Chemistry. / Spine title: Mercury speciation in its methylation by methylcobalamin. Bibliography: ℓ. 36-38.

Thesis (M.S.)--University of North Carolina Wilmington, 2009. / Title from PDF title page (February 23, 2010) Includes bibliographical references (p. 73-77)