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Computer-aided subsurface drainage system design and drafting.Chieng, Sie-Tan. January 1979 (has links)
No description available.
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Synthetic drain envelopes and soil particle distribution /Broadhead, Richard Grant. January 1981 (has links)
Thesis (M.S.)--Ohio State University, 1981. / Includes bibliographical references (leaves 89-91). Available online via OhioLINK's ETD Center
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Hydraulics analysis of subsurface flow in mature rock bed wetlands /Sun, Xiaoli, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 193-197). Also available on the Internet.
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Hydraulics analysis of subsurface flow in mature rock bed wetlandsSun, Xiaoli, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 193-197). Also available on the Internet.
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Influence of subsurface drainage and subirrigation practices on soil drainable porosityGao, Yuncai January 1990 (has links)
Subsurface drainage affects water table fluctuation patterns by removing the excess water from the soil. The annual average water table depths of the drained (A) and undrained (D) regimes are 0.83 and 0.48 m from the soil surface respectively. Subirrigation continuously provides water to the upper soil by capillary rise. The annual water table depths of the subirrigated regimes (B and C) are 0.61 and 0.70 m respectively. It is found that there is a significant curvilinear correlationship between the drainage flow rate and the water table height above the drain.
Soil drainable porosity of different regimes was investigated by using the soil water balance approach. The average drainable porosity of regimes A and B are 6.0% and 4.9% from water table rise, and 5.9% and 4.5% from water table drawdown , respectively. Subirrigation adversely affects the soil drainable porosity.
Soil drainable porosity is often considered as a constant. However, the results of this study indicate that it varies with the water table height above the drain. In the case of water table drawdown, this dependence can be successfully expressed by a negative exponential equation. In the case of water table rise, the correlation is not as significant, but there is still a trend that the drainable porosity decreases with the increase of the water table height above the drain.
Evapotranspiration (ET) is often neglected in soil water balance models for the drain-able porosity determination. This may result in some errors. In this study, the potential ET rate was computed by the Penman and Hargreaves methods. These two methods give very similar ET values for the studied area. It is assumed that actual ET equals to the potential ET rate when the ground water table is close to the soil surface. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
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Meltwater generation and drainage system development on an Antarctic cold-based glacierMacDonell, Shelley, n/a January 2009 (has links)
Drainage systems on cold-based glaciers are often thought to be simple systems that can be approximated from the supraglacial components of temperate glaciers. Most studies concerning cold-based glacier drainage systems have only considered one facet of the system, with little regard for how the system components interact. Studying each component independently of the whole system constrains our ability to model drainage system function and development. This in turn restricts our potential to predict how drainage systems of cold glaciers may respond to environmental change. The overarching aim of this thesis was to understand drainage system development of a cold-based glacier, and to assess whether our current understanding of supraglacial hydrological systems is consistent with the drainage systems that form on cold-based glaciers. This thesis evaluated the drainage system of the Wright Lower Glacier, McMurdo Dry Valleys, Antarctica, during the 2004/05, 2005/06 and 2006/07 ablation seasons. The study incorporated field, laboratory and numerical analyses, which resulted in a deeper understanding of the spatial and temporal variability of meltwater generation, drainage pathways, water stores and bulk discharge from the glacier. The findings showed that melt variability was driven by sediment and topographic variations, and that water storage in the form of cryoconite holes, intergranular flow, supraglacial ponds and refreezing dictated meltwater transmission to the glacier outlet. These results indicated that the structure, function and variability of the drainage system were inherently more complex than previous studies on supraglacial drainage systems had suggested. These new insights were combined together to construct a new conceptual model of the drainage system structure of a cold-based glacier. However, before the conceptual model can be used to produce a numerical model of drainage system function or development on cold-based glaciers, several issues need to be addressed. These include: refined methods for quantifying meltwater generation in cold, arid environments; methods to measure water storage on and under the glacier surface; further understanding of the development of permeable ice; and a better technique to quantify cryoconite hole connectivity.
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An analysis of the choice and application of two solute transport models in the upper Santa Cruz basinWeaver, Jeffrey Dale, January 1989 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1989. / Includes bibliographical references (leaves 81-84).
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Influence of solids on hydraulic and treatment properties of submerged-flow wetlandsRegmi, Tulsi January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves [135]-139). Also available on the Internet.
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Analyse de l'efficacite de deux reseaux de drainage souterrain de la region de Nicolet.Asselin, Rémi, 1948- January 1980 (has links)
No description available.
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Field testing of an agricultural land drainage computer modelPeyrow, Farzad January 1986 (has links)
No description available.
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