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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 30 for “"HYDRUS"”.
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Water Fluxes in Soil-Pavement Systems: Integrating Trees, Soils and Infrastructure
… and validated a soil water flow model, HYDRUS-1D, to predict soil water distribution for different rooting depths, soil textures and pavement thicknesses. Trees in paved tree pits grew larger, with stem diameters 29% (Mountains) and 51% (Coastal Plain) greater. Roots developed faster …
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An evaluation of unsaturated flow models in an arid climate
… The two models selected for this evaluation were HYDRUS-1D [Simunek et al., 1998] and the SHAW model [Flerchinger and Saxton, 1989]. Approximately 5 years of soil-water and atmospheric data collected from an instrumented weighing lysimeter site near the RWMS were used for building the models with …
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The Hillslope Hydrology of a Mountain Pasture: The Influence of Subsurface Flow on Nitrate and Ammonium Transport
… area located at the base of the watershed. The HYDRUS 2-D flow and transport model was used to predict and simulate subsurface flow. Predicted flow was coupled with observed field nutrient data to quantify nutrient flux as a function of slope location. HYDRUS 2-D was capable of simulating …
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An Experimental Study on the Infiltration Potential of Stormwater Ponds in Zeekoe Catchment, Cape Town, South Africa
… a finite element numerical modelling software (HYDRUS 2-D) to estimate the range of recharge rates for the study area. Based on field infiltration test results, the hydraulic conductivity was found to be 0.3 19.9 cm/hr; typical for silty sands to fine sands. Hydraulic conductivities estimated in …
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The effects of winter cover cropping on nutrient leaching through repacked soil columns
… one-dimensional water and solute transport model HYDRUS-1D to quantify and understand the potential decrease in nitrogen and phosphorus loss through tile drainage due to cover crops, as well as compare the amount of nitrogen and phosphorus available in the soil at cash crop planting, with and …
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Sorption and degradation of pesticides in biopurification systems
… techniques present in the transport model HYDRUS-1D. The sorption strength of the different pesticides to the organic matrix, increased with decreasing mobility of the pesticides. Concerning increasing degradability of the pesticides, pesticides could be ranked as follows linuron > …
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Real-time control of soil moisture for efficient irrigation
… (PID) controller to minimize water use using HYDRUS- 1D, a software package for simulating the one-dimensional movement of water, heat, and solutes in porous media, to simulate soil moisture. In a direct comparison between the two controllers, the PID controller uses less water. However, small …
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TREE ROOT ENCROACHMENT ON LEVEE DRAINAGE SYSTEM
… drainage material. For the last study element, HYDRUS-2D was applied to understand the soil water movement in the levee. The typical toe drain and the geocomposite edge drain were considered, and the models were run under the ambient condition (unsaturated) and the flood condition (saturated). …
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Quantifying the contribution of bank storage due to an alteration in stream stage
… inputs for a two-dimensonal groundwater model (HYDRUS-2D), which was used to quantify bank storage under a variety of scenarios. Multiple scenarios were studied to answer the research questions; these included variations in the flood stage, flood duration, and variations to the alluvial …
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Water Flow and Chemical Transport in a Subsurface Drained Watershed
… method performed well in comparison with the HYDRUS numerical model. Chapter 6 evaluates the chemical transport processes with a special focus on preferential flow and transport, providing insight into associated governing factors. Finally, the last chapter provides conclusions and suggestions …
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Budget and fluxes of nitrogen in mountainous agroecosystems in a summer monsoonal climate under intensive land use
… using 15N tracer. N leaching was simulated with Hydrus 2D. The comparison of 4 N fertilization levels (0, 150, 250 and 350 kg N ha-1) revealed that already 150 kg N ha-1 is sufficient to reach the maximal yield of radishes. Based on the low results of fertilizer N use efficiency (FNUE), we …
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Infiltration Models for Engineered Media in Living Roofs and Bioretention
… to simulated large inflows was realized in the HYDRUS-1D software, which can numerically solve the Richards equation for uniform flow modeling as well as offers a mobile-immobile model for preferential flow modeling. The magnitudes of Ks values range 10-2 to 10-1 cm/s. The measured WRC data show …
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Balancing the Water Budget: the effect of plant functional type on infiltration to harvest ratios in stormwater bioretention cells
… CSR is likely feasible. Hydraulic simulations (Hydrus 1D) were conducted for each scenario in all eight climate zones and revealed significant differences in evapotranspirative harvest and I:H ratios in simulated BRCs. Competitive woody plants had the highest evapotranspiration and lowest I:H …
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Evaluating the Hydrologic and Thermal Performance of a Green Roof in Syracuse: Measurements and Modeling of a Full-Scale System
… on hydrologic performance were modelled using HYDRUS-1D. Five 24-hour design storms were applied to predict the retention and detention performance. A 4% improvement in retention performance was calculated for 7-year-old growth medium for significant storms over the original medium. Runoff was …
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Impacto de la zona no saturada en el transporte de metales pesados y compuestos de nitrógeno (amonio, nitritos, y nitratos), en el área industrial de Bahía Blanca
… de agua. La calibración de un modelo numérico (HYDRUS 2D/3D) permitió representar correctamente el comportamiento hidrodinámico de la ZNS. Se cuantificó la retención de cadmio (Cd) en tres niveles del subsuelo de la parcela experimental. La afinidad del Cd por los niveles analizados fue en el …
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Quantification of wildfire-induced perturbations to soil-water retention curves and their impact on rainfall runoff
… in which we solved Richards equation with HYDRUS 1-D and with parameters constrained from burned and unburned SWRCs. These simulations suggest that the most commonly observed perturbations to SWRCs decrease time to ponding and strongly increase runoff generation at the sub-hourly timescales …
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Water Transport in the Vadose Zone and Hydrological Processes in Soil-Plant-Atmosphere Continuum (SPAC) in West Texas, USA
… precipitation. Soil water monitoring and HYDRUS simulations show that typical rainfall events in summer 2022 can hardly penetrate 40 cm of the soil profile in semi-arid West Texas. However, the uncommon extended rainfall events in the summer of 2023 penetrated deeper than 100 cm below the …
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Soilless Substrate Hydrology and Subsequent Impacts on Plant-Water Relations of Containerized Crops
… those in unaltered (control) pine bark. Finally, HYDRUS models were utilized to simulate water flux through containerized substrates. These models allowed for better understanding of how individual hydraulic properties influence substrate water flux, and provided insight towards proportions of …
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Sorption and leaching of glyphosate on partly sealed urban areas
… wurden mit dem numerischen Transportmodell HYDRUS-1D angepasst. Die beste Anpassung wurde bei einem Modell mit zwei Domänen und nicht-linearer Sorption, mit einem Kf ≤ 1 mg1-n Ln kg-1, erreicht. Der für den Grobsand aus den Durchbruchskurven der Säulenversuche errechnete Kf Wert ist eine …
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Cosmic-ray neutron sensing for soil moisture measurements in cropped fields
… sunflower period. A modelling framework coupling HYDRUS-1D and PEST was applied. Subsequently, field-scale soil hydraulic properties were compared against local scale soil properties (modelling and measurements). Successful results were obtained here, despite large difference in support volume. …
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