Studies on the genesis of selected soils of Oklahoma

Scope and method of study. Chapter 1 is a discussion of amounts of dispersion and soil properties associated with dispersion in some soil horizons affected by dispersion from soils of Oklahoma. Chapter 2 is a summary of the effects of addition of amending materials on soil properties associated with dispersion in some of the soil horizons discussed in Chapter 1. Materials tested for amending potential included gypsum, hydrated lime, cement kiln dust, fly ash, humate, calcium chloride, and sulfuric acid. Chapter 3 is an evaluation of the temporal effects of rainfall on the temperature and chemistry of water in a shallow, unconfined aquifer in sediments along Boomer Creek in the Stillwater, Oklahoma vicinity.; Findings and conclusions. Amount of dispersion measured in soil horizons ranged from 0 to 96 percent. Soil horizons with greater than 65 percent dispersion have greater bulk density, pH, sodium adsorption ratio, and ratio of sodium ions to sum of sodium and calcium ions in soil water, and less clay and organic matter than less-dispersed horizons. Critical sodium adsorption ratios are 8.0 and 4.5 for moderately saline (electrical conductivity between 1.0 and 9.0 decisiemens per meter) and slightly saline (electrical conductivity less than 1.0 decisiemen per meter), respectively. Gypsum proved most effective for improving properties of soil horizons associated with dispersion. Few treatments lowered sodium adsorption ratios of tested horizons below critical values. Treatments were less effective on soil horizons with more clay and greater sodium adsorption ratios and electrical conductivities. Rainfall affected chemistry of water in the Boomer Creek aquifer for a longer time than temperatures in the aquifer. Antecedent moisture in the sediments and amount of rainfall influenced the impact of the rainfalls on the aquifer.