Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 291-296).

Thesis (Ph. D.)--Florida State University, 2006. / Advisor: James B. Elsner, Florida State University, College of Social Sciences, Dept. of Geography. Title and description from dissertation home page (Sept. 19, 2006). Document formatted into pages; contains x, 90 pages. Includes bibliographical references.

Thesis (M.S.)--Rhodes University, 2004. / Title from PDF t.p. (viewed on Apr. 30, 2006). Includes bibliographical reference (p. 171-182).

Thesis (M.S.)--University of North Texas, May, 2007. / Title from title page display. Includes bibliographical references.

Thesis (M.S.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed July 18, 2007. Includes bibliographical references (p. 96-98).

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of California, Davis, 2005. / Degree granted in Civil and Environmental Engineering. Also available via the World Wide Web. (Restricted to UC campuses)

In this diploma thesis the issue of drainage system influence on water regime of catchment area was solved. The aim of the thesis was to analyze influence of drainage system on specific catchment area using mathematical, hydrological and statistical methods. In the teoretical part, the thesis describes the issue of drainage (specifically the drainage system of area of the Czech republic) and the influence of drainage system on water regime. In the practical part an analysis of the catchment area of Kopaninský creek and subcatchment areas P6, P52 and P53 was performed. At all of those areas, certains parts are dewatered by subsurface systematic drainage system, those parts are described in detail. The runoff coefficients and specific runoff from each subcatchment areas in different time interval were calculated and observed. Runoff separation and precipitation-runoff situation analysis were performed. The results are evaulated in the chapter Results and Discussion.

Agricultural runoff is a major non-point source pollutant in the Midwest and has been documented as a significant contributor to nutrient loads in the Mississippi River and subsequent hypoxic conditions in the Gulf of Mexico. In an attempt to minimize eutrophication, researchers have been collaborating with farmers to improve best management practices targeting nutrient retention. Over the past four decades riparian buffers have proven effective in retaining nutrients and sediment from agricultural runoff. We hypothesize that the addition of biochar to vegetated buffers can further improve nutrient attenuation by enhancing nutrient adsorption and cycling soil physical, chemical, and biological properties. In June 2012, fifteen flumes were established adjacent to fifteen existing flumes that were installed in 2008 for a related study at Southern Illinois University's farms. Each flume was either vegetated and/or amended with one of ten treatments and replicated three times: 1) giant cane (Arundinaria gigantea (Walt.) Muhl) established in 2008; 2) Kentucky bluegrass (Poa pratensis L.); 3) orchardgrass (Dactylis glomerata L.); 4) giant cane and compost (i.e., horse manure and mushroom compost); 5) biochar (i.e., pine and oak feedstock pyrolyzed between 450 °C and 650 °C.); 6) biochar and giant cane; 7) biochar, giant cane, and compost; 8) corn; 9) volunteer herbaceous species; and 10) a non-amended, non-vegetated control. Soil samples were collected prior to the application of soil amendments and nutrients were assessed annually. Surface runoff samples were collected from significant rain events (i.e., precipitation > 2.5 cm) and analyzed for nutrient and sediment levels. Data indicate that various combinations of biochar, compost, and giant cane were successful at reducing the frequency of surface runoff events as well as reducing concentrations of NO3- and NH4+ in agricultural surface runoff. Concentrations of dissolved reactive phosphorus (DRP) were greatly reduced when biochar and giant cane were present in the buffer without the addition of compost. Total phosphorus (TP) concentrations were lowest for the established giant cane treatment. There were no significant differences in the concentrations of total suspended solids (TSS) among the various buffer treatments. Data from this study are promising for the incorporation of biochar, compost, and giant cane into vegetated buffers to reduce the concentration of nutrients in agricultural surface runoff.

abstract: Nitrate contamination to groundwater and surface water is a serious problem in areas with high agricultural production due to over application of fertilizers. There is a need for alternative technologies to reduce nutrient runoff without compromising yield. Carbon nanoparticles have adsorptive properties and have shown to improve germination and yield of a variety of crops. Graphite nanoparticles (CNP) were studied under a variety of different fertilizer conditions to grow lettuce for the three seasons of summer, fall, and winter. The aim of this thesis was to quantify the effect of CNPs on nitrate leaching and lettuce growth. This was accomplished by measuring the lettuce leaf yield, formulating a nutrient balance using the leachate, plant tissue, and soil data, and changing the hydraulic conductivity of the soil to assess the effect on nutrient mobility. summer and fall experiments used Arizona soil with different amounts of nitrogen, phosphorus, and potassium (NPK) fertilizer being applied to the soil with and without CNPs. The winter experiments used three different soil blends of Arizona soil, Arizona soil blended with 30% sand, and Arizona soil blended with 70% sand with a constant fertilizer treatment of 30% NPK with and without CNPs. The results showed that the 70% NPK with CNP treatment was best at reducing the amount of nitrate leached while having little to no compromise in yield. The winter experiments showed that the effectiveness of CNPs in reducing nitrate leaching and enhancing yield, improved with the higher the hydraulic conductivity of the soil. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018