The influence of bulk density on saturated, unsaturated hydraulic conductivity , diffusivity and water con tent was measured on undisturbed and disturbed soil samples of Vernal sandy loam and Nibley silty clay loam. Bulk density was changed by artificially compacting the samples.
There was a very large decrease in hydraulic conductivity and diffusivity as water content decreased as has been noted by many others . For the disturbed and compacted samples of the Vernal sandy loam, the water content was higher at .33 and 1.0 bar suction than for the disturbed-uncompacted samples. The same general effect was noted for the undisturbed samples, but differences due to treatment were small. The reverse was true at .05 bars.
In the Nibley silty clay loam samples, water content was higher for the uncompacted than for the compacted samples at all suctions applied. The effect of compaction on unsaturated hydraulic conductivity and diffusivity was not consistent. At the same value of water content, both diffusivity and unsaturated hydraulic conductivity were sometimes higher in the compacted samples, others lower than in the uncompacted