Index Catalog // ScholarsArchive@OSU

Creator:: Selker, John S. and Rupp, David E.
Abstract:: Quality concerns drive many water studies and practices, but obtaining samples from water bodies over time and space for quality determination is often difficult and expensive. We present a low-cost approach that allows integration of water samples over timescales of days to months to allow more widely distributed acquisition of...
Resource Type:: Article
Full Text:: sampler An environmentally driven time-integrating water sampler John S. Selker and David E. Rupp

Creator:: Rupp, David E. and Selker, John S.
Abstract:: Solutions to the Boussinesq equation describing drainage into a fully penetrating channel have been used for aquifer characterization. Two analytical solutions exist for early- and late-time drainage from a saturated, homogeneous, and horizontal aquifer following instantaneous drawdown. The solutions for discharge Q can be expressed as dQ/dt = −aQ [superscript...
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Full Text:: hydraulic conductivity profile David E. Rupp and John S. Selker Department of Bioengineering, Oregon State

Creator:: Rupp, David E. and Selker, John S.
Abstract:: The method of recession analysis proposed by Brutsaert and Nieber (1977) remains one of the few analytical tools for estimating aquifer hydraulic parameters at the field scale and beyond. In the method, the recession hydrograph is examined as −dQ/dt = f(Q), where Q is aquifer discharge and f is an...
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Full Text:: recession hydrographs from sloping aquifers David E. Rupp1,2 and John S. Selker1 Received 2 April 2006

Creator:: Stewart, Ryan D., Rupp, David E., Abou Najm, Majdi R., and Selker, John S.
Abstract:: A soil’s capillarity, associated with the parameter sorptivity, is a dominant control on infiltration, particularly at the onset of rainfall or irrigation. Many mathematical models used to estimate sorptivity are only valid for dry soils. This paper examines how sorptivity and its capillary component (as wetting front potential) change with...
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Full Text:: D. Stewart,1 David E. Rupp,2 Majdi R. Abou Najm,3 and John S. Selker1 Received 14 February 2013

Creator:: Bogaart, Patrick W., Rupp, David E., Selker, John S., and van der Velde, Ype
Abstract:: Numerical solutions to the nonlinear Boussinesq equation, applied to a steeply sloping aquifer and assuming uniform hydraulic conductivity, indicate that late-time recession discharge decreases nearly linearly in time. When recession discharge is characterized by -dQ/dt=aQ[superscript b], this is equivalent to constant dQ/dt or b=0. This result suggests that a previously...
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Full Text:: Late-time drainage from a sloping Boussinesq aquifer Patrick W. Bogaart,1 David E. Rupp,2 John S

Creator:: Stewart, Ryan D., Abou Najm, Majdi R., Rupp, David E., and Selker, John S.
Abstract:: Shrinkage cracks in soil function as a dominant control on the partitioning and distribution of moisture fluxes in the vadose zone. Their dynamics influence moisture balance and control water availability for runoff, deep infiltration, and near-surface storage. We present a new low-cost field instrument to monitor the temporal change in...
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Full Text:: D. Stewart 1* , Majdi R. Abou Najm 1,2,3 , David E. Rupp 4,5 , John S. Selker 1 2 1

Creator:: Stewart, Ryan D., Abou Najm, Majdi R., Rupp, David E., and Selker, John S.
Abstract:: Current laboratory methods for determining volume and bulk density of soil clods include dipping saran-coated clods in water (a destructive process due to the permanent coating), performing physical measurements on samples with well-defined geometries, or using expensive equipment and proprietary software (such as laser scanners). We propose an alternative method...
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Full Text:: the Soil Shrinkage Curve 1 Ryan D. Stewart 1 *, Majdi R. Abou Najm 1,2 , David E. Rupp 3,4 , John

Creator:: Stewart, Ryan D., Hut, Rolf, Rupp, David E., Gupta, Hoshin, and Selker, John S.
Abstract:: We propose a novel, accurate quantification of precipitation and evaporation, as needed to understand fundamental hydrologic processes. Our system uses a collection vessel placed on top of a slender rod that is securely fixed at its base. As the vessel is deflected, either by manual perturbation or ambient forcing (for...
Resource Type:: Article
Full Text:: recorder A resonating rainfall and evaporation recorder Ryan D. Stewart,1 Rolf Hut,2 David E. Rupp,3

Creator:: Rupp, David E., Keim, Richard F., Ossiander, Mina, Brugnach, Marcela, and Selker, John S.
Abstract:: Multiplicative random cascades (MRCs) can parsimoniously generate highly intermittent patterns similar to those in rainfall. The elemental MRC model parameter is the cascade weight, which determines how rainfall at one scale is partitioned at the next smallest scale in the cascade. While it is known that the probability density of...
Resource Type:: Article
Full Text:: cascades for temporal rainfall disaggregation David E. Rupp,1,2 Richard F. Keim,3 Mina Ossiander,4 Marcela

Creator:: Stewart, Ryan D., Abou Najm, Majdi R., Rupp, David E., Lane, John W., Uribe, Hamil C., Luis Arumí, José, and Selker, John S.
Abstract:: Irrigation experiments on 12 instrumented field plots were used to assess the impact of dynamic soil crack networks on infiltration and run-off. During applications of intensity similar to a heavy rainstorm, water was seen being preferentially delivered within the soil profile. However, run-off was not observed until soil water content...
Resource Type:: Article
Full Text:: shrink–swell clay soils Ryan D. Stewart,1,7* Majdi R. Abou Najm,2 David E. Rupp,3 John W. Lane,4 Hamil C

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