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Full-Text Articles in Water Resource Management
Inverse Method For Simultaneous Determination Of Soil Water Flux Density And Thermal Properties With A Penta-Needle Heat Pulse Probe, Changbing Yang, Masaru Sakai, Scott B. Jones
Inverse Method For Simultaneous Determination Of Soil Water Flux Density And Thermal Properties With A Penta-Needle Heat Pulse Probe, Changbing Yang, Masaru Sakai, Scott B. Jones
Plants, Soils, and Climate Faculty Publications
An accurate method for determination of in situ soil water flux density continues to be the most sought after and yet elusive hydrologic measurement. The penta-needle heat pulse probe (PHPP) employs a central heater needle surrounded by an orthogonal arrangement of four thermistor needles for two-component water flux density estimation. An analytical solution and inverse fitting method are presented for simultaneous estimation of thermal properties and soil water flux density using PHPP measurements. The approach yields estimates of both components of the flux in a plane normal to the axis of the PHPP needles. The method was evaluated using data …
Numerical Evaluation Of Subsurface Soil Water Evaporation Derived From Sensible Heat Balance, Masaru Sakai, Scott B. Jones, Markus Tuller
Numerical Evaluation Of Subsurface Soil Water Evaporation Derived From Sensible Heat Balance, Masaru Sakai, Scott B. Jones, Markus Tuller
Plants, Soils, and Climate Faculty Publications
A recently introduced measurement approach allows in situ determination of subsurface soil water evaporation by means of heat-pulse probes (HPP). The latent heat component of subsurface evaporation is estimated from the residual of the sensible heat balance. This heat balance method requires measurement of vertical soil temperature and estimates of thermal properties for soil water evaporation determination. Our objective was to employ numerically simulated thermal and hydraulic processes using constant or diurnally cycled surface boundary conditions to evaluate and understand this technique. Three observation grid spacings, namely, 6 mm (tri-needle HPP), 3 mm (penta-needle HPP) and 1 mm, along with …
Geophysical Imaging Of Watershed Subsurface Patterns And Prediction Of Soil Texture And Water Holding Capacity, H. Abdu, D. A. Robinson, M. Seyfried, Scott B. Jones
Geophysical Imaging Of Watershed Subsurface Patterns And Prediction Of Soil Texture And Water Holding Capacity, H. Abdu, D. A. Robinson, M. Seyfried, Scott B. Jones
Plants, Soils, and Climate Faculty Publications
The spatial distribution of subsurface soil textural properties across the landscape is an important control on the hydrological and ecological function of a watershed. Traditional methods of mapping soils involving subjective assignment of soil boundaries are inadequate for studies requiring a quantitative assessment of the landscape and its subsurface connectivity and storage capacity. Geophysical methods such as electromagnetic induction (EMI) provide the possibility of obtaining high-resolution images across a landscape to identify subtle changes in subsurface soil patterns. In this work we show how EMI can be used to image the subsurface of a ∼38 ha watershed. We present an …
Micro-Structural And Phase Configuration Effects Determining Water Content: Dielectric Relationships Of Aggregated Porous Media, J. M. Blonquist, Jr., Scott B. Jones, I. Lebron, D. A. Robinson
Micro-Structural And Phase Configuration Effects Determining Water Content: Dielectric Relationships Of Aggregated Porous Media, J. M. Blonquist, Jr., Scott B. Jones, I. Lebron, D. A. Robinson
Plants, Soils, and Climate Faculty Publications
Many porous media in which we determine water content are aggregated and characterized by a dual-porosity pore network, composed of interaggregate pores and intra-aggregate pores. This paper reports sample-scale permittivity measurements made in four stable aggregate media with dual porosity. Results indicate two distinct dielectric responses depending on whether the aggregates are surrounded by water or air. We relate transitions in the permittivity response to the water retention characteristic (WRC), showing that after the interaggregate pores have drained, the slope of the water content–permittivity relationship is significantly reduced (permittivity values ranging from 5 to 7). The hydraulic critical water content …