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.
|Paper - American Society of Agricultural Engineers
|Published - 1986
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)