abstract to estimate spatial variability of soil hydraulic functions, scaling methods were developed and have been widely used. among these functions, physically based methods have been found more desirable because of possibility of estimating soil hydraulic functions from soil physical properties. in this paper, a new and physically based method has been described for scaling soil hydraulic co...

Subgrade moisture content varies with environmental and soil conditions and has significant influence on pavement performance. Therefore, it is important to establish realistic estimates of expected subgrade moisture contents to account for the effects of this variable on predicted pavement performance during the design stage properly. The initial boundary soil suction profile for a given pavem...

Evaluation of flow and transport processes in a watershed-scale requires that the watershed be divided into homogenous spatial units referred to as hydrologically similar units (HSUs). Although a few discretization schemes are already in use, a universally acceptable method of obtaining HSUs is yet to emerge. In this study, we developed a fuzzy inference system (FIS) to classify the saturated h...

Tillage operations disrupt surface layers of agricultural soils, creating a loosened structure with a substantial proportion of interaggregate porosity that enhances liquid and gaseous exchange properties favorable for plant growth. Unfortunately, such desirable soil tilth is structurally unstable and is susceptible to change by subsequent wetting and drying processes and other mechanical stres...

The relationships between hydraulic and photosynthetic properties in plants have been widely studied, but much less is known about how these properties are linked to water-source partitioning, the spatial and temporal separation of water sources in ecosystems. Plant water-source partitioning is often influenced by the proximity of groundwater from the natural surface. We studied the water acqui...

Inverse solution techniques currently used for estimating unsaturated soil hydraulic functions from laboratory outflow experiments use cumulative outflow only in combination with initial and final soil water pressure head values. Additional soil water information is needed to improve the estimation procedure and to minimize uniqueness problems. It was the objective of this study to experimental...

Novel evaporation experiment to determine soil hydraulic properties K. Schneider, O. Ippisch, and K. Roth Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany Interdisciplinary Center for Scientific Computing, University of Heidelberg, Heidelberg, Germany Received: 24 April 2006 – Accepted: 27 April 2006 – Published: 29 June 2006 Correspondence to: K. Schneider (kla...

Stochastic modeling of soil water fluxes in the absence of measured hydraulic parameters requires a knowledge of the expected istribution of the hydraulic parameters in different soil types. Predictive relationships describing the hydraulic parameter distributions must be developed based on the common descriptors of the physical properties of soils (e.g., texture, structure, particle size distr...

Experimentally determined values of unsaturated soil hydraulic conductivity are presented for an Alfisol of the county of Piracicaba, S.P., Brazil. Simultaneous measurements of soil water content and pressure head are made along a 125 m transect within an irrigated field during the internal drainage process. Calculations of the soil hydraulic conductivity were made using the instantaneous profi...

abstract disc infiltrometer is one of those devices that used in recent years in measurement of hydraulic conductivity of entire soil. in order to analyze the data taken by disc infiltrometer a variety of methods based on wooding’s base analyze have been introduced. the objective of this study was to compare the performances of ankeny and weir methods for predicting soil hydraulic properties us...