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dc.contributor.advisorGantzer, Clark Jamesen
dc.contributor.authorLee, Sang Soo, 1978-en_US
dc.date.issued2006eng
dc.date.submitted2006 Fallen
dc.descriptionThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.en_US
dc.descriptionTitle from title screen of research.pdf file (viewed on August 24, 2007)en_US
dc.descriptionVita.en_US
dc.descriptionIncludes bibliographical references.en_US
dc.descriptionThesis (M.S.) University of Missouri-Columbia 2006.en_US
dc.descriptionDissertations, Academic -- University of Missouri--Columbia -- Soil, environmental and atmospheric sciences.en_US
dc.description.abstractRainfall on bare soil breaks soil aggregates, detaching particles, plugging pores and decreasing porosity in the top few mm of soil. This reduces hydraulic conductivity and increases runoff through a process known as surface sealing. The objectives of this study are to measure saturated hydraulic conductivity (Ksat) of surface seals developed on bare Mexico silt loam (Aeric Vertic Epiaqualfs) during a simulated rainfall event, to evaluate the effect of anionic polyacrylamide (PAM) for maintaining high Ksat, and to evaluate models of sealing using total porosity, pore-size distribution collected with high-resolution X-ray computed tomography (HRCT). The study used a factorial design. Factors included rainfall duration (0-, 7.5-, 15-, 30-, and 60-min) at 55-mm hr-1 intensity, and an untreated soil or a soil amended with 20-kg ha-1 PAM. Application of PAM for various rainfall durations maintained from 20% to 41% higher Ksat than did untreated soil, for all times tested. Results indicated density ([rho]) increased, and total porosity and pore-size decreased rapidly after a 15-min rainfall. HRCT-[rho] data helped identify the best model selection for characterizing seal [rho] profile. Although the cost is expensive, HRCT image is a valuable tool to measure soil properties by analyzing soil thickness down to 0.015-mm. The study confirms that HRCT-analysis of soil allows accurate and direct measurements of seal effects on water flow and documents the usefulness of PAM for reducing surface sealing.en_US
dc.identifier.merlin.b59445634en_US
dc.identifier.oclc166290506en_US
dc.identifier.otherLeeS-120706-T6024en_US
dc.identifier.urihttp://hdl.handle.net/10355/4507
dc.publisherUniversity of Missouri--Columbiaen_US
dc.relation.ispartofcollection2006 Freely available theses (MU)
dc.relation.ispartofcommunityUniversity of Missouri-Columbia. Graduate School. Theses and Dissertations. Theses. 2006 Theses
dc.subject.lcshSoil permeability -- Measurementen_US
dc.subject.lcshSoil crustingen_US
dc.subject.lcshSilt loamen_US
dc.subject.lcshRain and rainfallen_US
dc.subject.lcshRunoffen_US
dc.titleSoil surface-seal measurement using high-resolution x-ray computed tomography (HRCT)en_US
dc.typeThesisen_US
thesis.degree.disciplineSoil, environmental and atmospheric sciencesen_US
thesis.degree.disciplineSoil, environmental and atmospheric scienceseng
thesis.degree.grantorUniversity of Missouri--Columbiaen_US
thesis.degree.levelMastersen_US
thesis.degree.nameM.S.en_US


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