# FIELD METHODS FOR DETERMINING UNSATURATED HYDRAULIC CONDUCTIVITY.

M. Yitayew, J. Watson

Research output: Contribution to journalConference article

1 Citation (Scopus)

### Abstract

Mathematical models have been developed which describe soil water movement under point and disc sources. Results of these models suggest the possibility of estimating unsaturated hydraulic conductivity if the variables K//o and alpha in the exponential function K( psi ) equals K//o exp( alpha psi ) are evaluated. Two approaches to evaluate these parameters in the field are proposed. Method 1 involves application of a constant flux from a simple constant flow device and measuring the steady state wetted radius for two different values of flux, and Method 2 makes use of a sorptivity tube type device - with a given potential at the soil surface and measurement of the steady flow rate and wetted radii. These measurements allow for the algebraic solution of the hydraulic conductivity function.

Original language English (US) Paper - American Society of Agricultural Engineers Published - Dec 1 1986

### Fingerprint

unsaturated hydraulic conductivity
Soil
Water Movements
soil water movement
Equipment and Supplies
hydraulic conductivity
Theoretical Models
mathematical models
methodology
soil

### All Science Journal Classification (ASJC) codes

• Agricultural and Biological Sciences (miscellaneous)

### Cite this

title = "FIELD METHODS FOR DETERMINING UNSATURATED HYDRAULIC CONDUCTIVITY.",
abstract = "Mathematical models have been developed which describe soil water movement under point and disc sources. Results of these models suggest the possibility of estimating unsaturated hydraulic conductivity if the variables K//o and alpha in the exponential function K( psi ) equals K//o exp( alpha psi ) are evaluated. Two approaches to evaluate these parameters in the field are proposed. Method 1 involves application of a constant flux from a simple constant flow device and measuring the steady state wetted radius for two different values of flux, and Method 2 makes use of a sorptivity tube type device - with a given potential at the soil surface and measurement of the steady flow rate and wetted radii. These measurements allow for the algebraic solution of the hydraulic conductivity function.",
author = "M. Yitayew and J. Watson",
year = "1986",
month = "12",
day = "1",
language = "English (US)",
journal = "Paper - American Society of Agricultural Engineers",
issn = "0145-0166",

}

In: Paper - American Society of Agricultural Engineers, 01.12.1986.

Research output: Contribution to journalConference article

TY - JOUR

T1 - FIELD METHODS FOR DETERMINING UNSATURATED HYDRAULIC CONDUCTIVITY.

AU - Yitayew, M.

AU - Watson, J.

PY - 1986/12/1

Y1 - 1986/12/1

N2 - Mathematical models have been developed which describe soil water movement under point and disc sources. Results of these models suggest the possibility of estimating unsaturated hydraulic conductivity if the variables K//o and alpha in the exponential function K( psi ) equals K//o exp( alpha psi ) are evaluated. Two approaches to evaluate these parameters in the field are proposed. Method 1 involves application of a constant flux from a simple constant flow device and measuring the steady state wetted radius for two different values of flux, and Method 2 makes use of a sorptivity tube type device - with a given potential at the soil surface and measurement of the steady flow rate and wetted radii. These measurements allow for the algebraic solution of the hydraulic conductivity function.

AB - Mathematical models have been developed which describe soil water movement under point and disc sources. Results of these models suggest the possibility of estimating unsaturated hydraulic conductivity if the variables K//o and alpha in the exponential function K( psi ) equals K//o exp( alpha psi ) are evaluated. Two approaches to evaluate these parameters in the field are proposed. Method 1 involves application of a constant flux from a simple constant flow device and measuring the steady state wetted radius for two different values of flux, and Method 2 makes use of a sorptivity tube type device - with a given potential at the soil surface and measurement of the steady flow rate and wetted radii. These measurements allow for the algebraic solution of the hydraulic conductivity function.

UR - http://www.scopus.com/inward/record.url?scp=0022986048&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022986048&partnerID=8YFLogxK

M3 - Conference article

AN - SCOPUS:0022986048

JO - Paper - American Society of Agricultural Engineers

JF - Paper - American Society of Agricultural Engineers

SN - 0145-0166

ER -