Spatial variability of hydrologic properties in an irrigated soil
Publisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.Abstract
The spatial and temporal variability of water content, soil water tension, and derived hydraulic conductivity parameters are analyzed using geostatistical methods. The measured data sets were obtained from a 1985 experiment near Las Cruces, New Mexico. Post-irrigation water content and tension measurements had been recorded over 44 days at 455 sampling locations along a 91 x 1.5-meter transect. Unsaturated hydraulic conductivity values are derived using the instantaneous profile formula, and an exponential model is used to obtain values of saturated hydraulic conductivity and pore-size distribution parameters. The exponential model is found to inadequately describe the conductivity data for tensions near saturation, because excessively large saturated hydraulic conductivity values are derived. Semivariogram analysis shows ranges of dependence of three to 32 meters for water content and six to 34 meters for tension. As water content decreases, the coefficient of variation and variance are found to increase.Type
textThesis-Reproduction (electronic)