Measurement of Subsurface Unsaturated Hydraulic Conductivity
Publication: Journal of Irrigation and Drainage Engineering
Volume 126, Issue 1
Abstract
Measurement of unsaturated hydraulic conductivity is needed for precise control of water and solutes in the vadose zone. Because of the spatial variation of soils, a large number of surface and subsurface measurements are needed to characterize a field. In this work, permeameters were developed and tested for estimating subsurface unsaturated hydraulic conductivity. The permeameters apply water under tension; they are easy to use and have adequate accuracy. Unsaturated hydraulic conductivity was determined by measuring the steady flow rates for various values of negative pressure. Tests using a soil of known hydraulic conductivity showed that the permeameters provided valid measurements. Two types were used, a porous cloth model that was inflated against the soil and a porous ceramic cup that was rigid. The field testing determined that a rigid design using a ceramic cup coupled to the soil by a layer of fine sand was easier to use, was reliable, and provided good results.
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Information & Authors
Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 126 • Issue 1 • January 2000
Pages: 21 - 27
History
Received: Sep 21, 1998
Published online: Jan 1, 2000
Published in print: Jan 2000
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