The effect of sand content upon cone index and selected physical properties
1980
BYRD, C. W. | CASSEL, D. K.
Soil collected from an induced tillage pan in the A2 horizon of a Norfolk sandy loam soil was fractionated into sand, silt, and clay separates and reconstituted, yielding four soil textures, each having approximately 5% clay, but with sand percentages ranging from 66.6 to 82.2%. Twelve soil cores for each texture were packed to bulk densities of 1.79 ± 0.03 g/cm. Cone index (CI), the soil water characteristic, pore-size distribution, and saturated hydraulic conductivity (K) were measured for the induced pan and the reconstituted soil cores.The cone indices for the undisturbed cores of induced pan were significantly greater than for the reconstituted soil for the same texture. Saturated hydraulic conductivity of the undisturbed pan was only slightly greater than for the disturbed pan material having the same texture. For the reconstituted soils, saturated hydraulic conductivity increased, and the volume of water-filled pores at soil water pressures less than —80 mb decreased as the percentage of sand increased. The cone index for each texture increased monotonically with decreasing soil water pressure, but no simple relationship between CI and texture was found. Regression equations relating CI to water content, percentage of sand, and the volume of pores greater than 150 μm in diameter were developed, were significant at the 0.0001 probability level, and explained 67 to 72% of the observed variability.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library