Soil Science Commons^™

Characterization Of Water Movement Into And Through Soils During And Immediately After Rainstorms, C. T. Haan

KWRRI Research Reports

The movement of water into and through soils in the unsaturated state is basic to many water resources problems including rainfall-runoff models, ground water recharge, irrigation, drainage, evapotranspiration and the movement of pollutants in soils. This study was conducted in an effort to determine if the flow equation based on Darcy's Law and the continuity equation could be used to describe watershed infiltration and thus be incorporated into hydrologic models.

The results of the study indicate that even on apparently uniform soils there is a great deal of variability in soil water properties. Handling this variability plus the difficulty of …

The Relation Between Soil Characteristics, Water Movement And Nitrate Contamination Of Ground Water, Grant W. Thomas, Matthew Mcmahon

KWRRI Research Reports

Soils from several areas in Kentucky were placed in columns and leached with Ca(NO₃)₂. Subsoils high in iron oxide were found to retard the leaching of nitrate very significantly. In other soils, the nitrate moved through as fast as or slightly faster than the water.

Field application of nitrogen to corn was most efficient when done in the spring or summer near the time that the corn takes it up. The one exception to this was a red soil, where fall application of nitrogen resulted in little loss due to the retarding effect mentioned in the …

Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part Ii, Vincent P. Drnevich, D. Raghu

KWRRI Research Reports

Four seismic field methods and a laboratory method are used to determine shear wave propagation velocities and shear moduli for two sites. The four seismic methods are: standard seismic refraction survey, down hole shooting refraction survey, transient Rayleigh wave survey, and crosshole shooting survey. A torsional resonant column apparatus was used for the laboratory tests. The cross hole shooting method gave the best results because direct measurements were made. Criteria for using this method are given. Methods which measure compression wave velocity give inconsistent results because the conversion to shear wave velocity is very sensitive to Poisson's ratio. Laboratory tests …

Location Of Solution Channels And Sinkholes At Dam Sites And Backwater Areas By Seismic Methods: Part I, Vincent P. Drnevich, S. R. Smith, E. P. Cleveland

KWRRI Research Reports

The basic concepts associated with the sledge hammer seismic refraction survey are reviewed and a modified version called down hole shooting is discussed. The latter method has distinct advantages for rock surface profiling. These include: calibration at the end points of the survey, measurement of vertical wave propagation velocities directly, and having a refracted wave ray path for almost the entire survey length.

The down hole shooting seismic refraction survey has been simulated with the digital computer. The method can handle any shaped rock surface profile and generates corresponding travel time curves for the forward and reverse profile surveys. This …