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Soil suspension dynamics and particle retention in a vertical column of the same soil in bulk
Abstract
During the soil suspension infiltration, particle retention within the initially air-dry and wet soil columns was measured at various vertical positions in the column by using attenuation of $\sp{241}$Am and $\sp{137}$Cs gamma-rays. The accumulation of suspension particles with suspension flow volume at a fixed position was described by an exponential equation. The largest increase in the mean bulk densities occurred between 0.5 to 2.5 mm of the initially air-dry and between 0.5 to 5.5 mm of the initially wet soil surface. Greater particle retention was observed in the initially wet soil columns as compared to the initially air-dry soil columns. Wetting the soil with water before applying suspension increased particle retention. The largest retardation in wetting front movement and decrease in inflow volume were obtained with treatment of Na metaphosphate soil suspension. The reduction in hydraulic conductivity $(\rm K\sb{s})$ due to particle retention was described very well as a function of time and as a function of outflow volume by using two new three-parameter exponential equations. The decrease in the hydraulic conductivity due to particle retention occurred within a shorter time and at a lower outflow volume for the initially wet conditions than for the initially air-dry conditions. A ratio of the fitted constants $\beta$/K$\rm \sb{s}$ is termed the clogging coefficient $\rm C\sb{c}.$ As the particle accumulation increased in the initially wet soil columns, larger $\rm C\sb{c}$ values for the initially wet treatments were obtained using the second three-parameter equation. The smaller $\rm C\sb{c}$ values due to less particle accumulation were obtained for the initially air-dry replicates as compared to the initially wet replicates.
Subject Area
Soil sciences|Agronomy|Hydrology
Recommended Citation
Gulser, Coskun, "Soil suspension dynamics and particle retention in a vertical column of the same soil in bulk" (1998). ETD collection for University of Nebraska-Lincoln. AAI9903766.
https://digitalcommons.unl.edu/dissertations/AAI9903766