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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Performance-based voluntary group contracts for nonpoint source water pollution control

Isik, Haci Bayram, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains viii, 129 p.; also includes graphics. Includes abstract and vita. Advisor: D. Lynn Forster, Dept. of Agricultural, Environmental, and Development Economics. Includes bibliographical references (p. 124-129).

Development of an integrated modeling system for supporting simulation and assessment of nonpoint source pollution

Chen, Bing. January 1900 (has links)
Thesis (Ph.D.)--The University of Regina (Canada), 2005. / Includes bibliographical references.

Linking field-scale phosphorus export to a watershed-scale model /

Freihoefer, Adam T. January 2007 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2007. / Includes bibliographical references (leaves 105-112).

Contaminant transport and mass transfer to runoff including infiltration

Weber, Sofie Aimee. January 1997 (has links) (PDF)
Thesis (M.S. - Department of Soil, Water and Environmental Science) - University of Arizona. / Includes bibliographical references (leaves 80-81

Performance-based payments for conservation experience from a water quality field experiment /

Maille, Peter J. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 169 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 122-132).

Acute Toxicity and Sub-Lethal Effects of Non-Point Source Pollutants on Invertebrates

Romano, Jocelyn Ann, January 2007 (has links)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.

An Investigation of the Performance of a Constructed Wetland in Treating Urban Stormwater

Carleton, James Nagle 05 May 1998 (has links)
This study investigated the pollutant removal performance of a constructed wetland treating stormwater runoff from a residential townhome complex in Manassas, Virginia. The facility was constructed by retrofitting a dry detention basin to retain a permanent shallow pool and included additional temporary storage to detain roughly the first half inch of rainfall for approximately 24 hours. Vegetation was allowed to establish itself through volunteer colonization, rather than active planting of selected wetland species. Flow measurements showed substantially greater volume passing through the outlet than entering through the single gaged inlet. The extra volume (about 41% of the total) was attributed to ungaged overland flow which drained a wooded/grassy area adjacent to the site. Mass balance calculations employing the rational method with a runoff coefficient of 0.2 to estimate the flow from this area showed good agreement between long-term total estimated inflow and measured outflow. However, this method was not effective in accounting for the discrepancies between inlet and outlet volumes of individual storms. Thirty-three runoff events were monitored between April, 1996 and May, 1997. Because of greater flow volumes passing through the outlet, constituent mass calculations which ignored the overland contribution generally exhibited higher loads exiting than entering the facility. With the results from a limited number of grab samples representing concentrations in overland input, estimated efficiencies improved substantially, showing overall net removal for most constituents. Less than one year after being retrofitted, the basin showed signs of beginning to develop a diverse wetland flora. / Master of Science

Assessing the pollution potential of non-point mine wastes on surface water using a geo-spatial modeling approach

Xiao, Huaguo, Ji, Wei. January 2004 (has links)
Thesis (Ph. D.)--Dept. of Geosciences and School of Computing and Engineering. University of Missouri--Kansas City, 2004. / "A dissertation in geosciences and computer networking." Advisor: Wei Ji. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Feb. 28, 2006. Includes bibliographical references (leaves 226-236). Online version of the print edition.

SET-WET: A Wetland Simulation Model to Optimize NPS Pollution Control

Lee, Erik Ryan 30 September 1999 (has links)
A dynamic, compartmental, continuously stirred tank reactor, simulation model (SET-WET) was developed for design and evaluation of constructed wetlands in order to optimize non-point source (NPS) pollution control measures. The model simulates the hydrologic, nitrogen, carbon, dissolved oxygen, bacteria, vegetative, phosphorous and sediment cycles of a wetland system. Written in Fortran 77, SET-WET models both free water surface (FWS) and sub-surface flow (SSF) wetlands and is designed in a modular manner which gives the user the flexibility to decide which cycles and processes to model. SET-WET differs from many existing wetland models in that it uses a system's approach, and limits the assumptions made concerning the interactions of the various nutrient cycles in a wetland system. It accounts for carbon and nitrogen interactions, as well as effect of oxygen levels upon microbial growth. It also directly links microbial growth and death to the consumption and transformations of nutrients in the wetland system. Many previous models have accounted for these interactions with zero and first order rate equations that assume rates are dependent only on initial concentrations. The SET-WET model is intended to be utilized with an existing NPS hydrologic simulation model, such as ANSWERS or BASINS, but may also be used in situations where measured input data to the wetland are available. The model was calibrated and validated using limited data collected at Benton, Kentucky. A non-parametric statistical analysis of the model's output indicated eight out of nine examined outflow predictions were not statistically different from the measured observations. Linear regression analysis showed that six out of nine examined parameters were statistically similar, and that within the expected operating range, all of the examined outflow parameters (9) were within the 95% confidence intervals of the regression lines. A sensitivity analysis showed the most significant input parameters to the model were those which directly affect bacterial growth and oxygen uptake and movement. The model was applied to a subwatershed in the Nomini Creek watershed located in Virginia. Two year simulations were completed for five separate wetland designs, with reductions in percentage of BOD5 (4%-45%), TSS (85%-100%), total nitrogen (42%-56%), and total phosphorous (38%-57%) comparable to levels reported by previous research. / Master of Science


Stazyk, Edmund C. 05 October 2006 (has links)
No description available.

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