Illman and Tartakovsky (2005a, 2005b) developed a new approach for the interpretation of three-dimensional pneumatic well tests conducted in porous or fractured geologic media, which is based on a straight-line analysis of late-time data. We modify this approach to interpret three-dimensional well tests in the saturated zone and use it to analyze the cross-hole hydraulic test data collected in ...

In this study, we measured the specific hydraulic conductivity (K) of MatrigelTM at 1% and 2% concentrations as a function of perfusion pressure (0 to 100 mmHg) and compared the results to predictions from two models: a fiber matrix model that predicted K of the gel based upon its composition, and a biphasic model that predicted changes in K caused by pressure induced compaction of the gels. Th...

The recession flow analysis of Brutsaert and Nieber [1977] extended by Troch et al. [1993] to estimate aquifer parameters (saturated hydraulic conductivity and mean aquifer depth) is examined by means of a numerical model. It is found to be reliable for the estimation of the catchment-scale saturated hydraulic conductivity and mean aquifer depth. Increasing the complexity of the synthetic water...

, Abstract Results of the laboratory reclamation of four sodic soils by the high salt water dilution method are reported. The exchangeable sodium percentage (ESP) of all soils was decreased by leaching with solutions of decreasing sodium but constant calcium concentration. Although a final leaching with water of low electrolyte concentration (EC,, < 100 micromhos/cm) did not produce a rapid dec...

[1] Simultaneous scaling of soil water retention and hydraulic conductivity functions provides an effective means to characterize the heterogeneity and spatial variability of soil hydraulic properties in a given study area. The statistical significance of this approach largely depends on the number of soil samples collected. Unfortunately, direct measurement of the soil hydraulic functions is t...

A pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root Lp(r) per m(2) of root surface area). Young plants of two rice (Oryza sativa L.) varieties (an upland variety, cv. Azucena and a lowland variety, cv. IR64) were grown for 31-40 d in 12 h days with 500 micromol m(-2) s(-1) PAR and day/night temperatures of 27 degrees C an...

abstract the temperature of water entering the soil or variation in soil temperature has a direct impact on soil hydraulic conductivity via the effect on water viscosity. in this research, the time variability of soil saturated hydraulic conductivity (ks) was studied. the relation between soil temperature and fluid viscosity with hydraulic conductivity were also studied. the necessary experimen...

abstract saturated hydraulic conductivity (ks) is needed for many studies related to water and solute transport, but often cannot be measured because of practical and/or cost-related reasons. nonparametric approaches are being used in various fields to estimate continuous variables. one type of the nonparametric lazy learning algorithms, a k-nearest neighbor (k-nn) algorithm, was introduced and...

This study aimed at optimizing horizontal subsurface flow constructed wetlands (CWs) to improve hydraulic performance and pollutant removal efficiency. A groundwater modeling package (MODFLOW) was used to optimize three design parameters (length-to-width ratio, inlet/outlet-to-length ratio, and substrate size configuration). Using the optimized parameters, three pilot-scale CWs were built to tr...

For decades it has been assumed that the largest vessels are generally found in roots and that vessel size and corresponding sapwood area-specific hydraulic conductivity are acropetally decreasing toward the distal twigs. However, recent studies from the perhumid tropics revealed a hump-shaped vessel size distribution. Worldwide tropical perhumid forests are extensively replaced by agroforestry...