TITLE:
Saturated Hydraulic Conductivity Changes with Time and Its Prediction at SAR and Salinity in Quevedo Region Soils
AUTHORS:
Abdelmonem Mohamed Amer, Carmen Suarez, Felix Valverde, Roberto Carranza, Leonardo Matute, Gabriel Delfini
KEYWORDS:
Saturated Hydraulic Conductivity, Empirical Models, Effluent Volume and SAR, Linear & Nonlinear Flux
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.17,
November
28,
2014
ABSTRACT: Darcy’s law
is applied to describe the steady flow processes in which the flux remains
constant with time along the conducting system. Due to the dispersion and
migration of colloidal particles and lodging in the soil pores the reduction in
hydraulic conductivity occurs with time in particular when the soil and the
percolating solution are affected by electrolyte concentration. Hence, the aim
of this study is to find empirical equations that can be used to predict the
flux with time. Data for the effluent volume versus time (up to 6 hours) which
was collected for three soils (located at Quevedo-Los Rios region) treated by two
salt solutions (5 and 50 meq/l) with different SAR values were used to test
certain mathematical forms of equations. Only four empirical equations were
found to perfectly fit the data (flux vs time) whereas, fitting the calculated
and measured data of the hydraulic conductivity for all soils produced
regression factors R2 ≥ 0.99.
So, these equations can be applied to predict the hydraulic conductivity and to
characterize the flow process at saturated conditions of the studied soils with
great confidence. The Hoerl function model was the best of all equations for
application as the fitting degrees were almost perfect for all studied soils at
5 and 50 meq/l. It was observed for all equations that one of the fitting
parameters would always represent the initial hydraulic conductivity (Kos) that was evaluated
graphically at zero time by extrapolation.