Water saturation and cation exchange capacity are the most significant parameters used to calculate a hydrocarbon zone potential. In clean formations, by applying the famous Archie model, which assumes that in the formation the only electric conductor is the formation water, the water saturation can be calculated. Additionally, in shaly sand formations this assumption may not be true as the ion...

Nowadays, applying soil amendments is one of the most important ways to cope with water shortages and improve soil physical properties. In this regard, a greenhouse experiment was conducted to study the effect of different levels of irrigation water and wheat straw biochar on physical and chemical properties of a sandy loam soil, after harvesting faba bean. The experiment was performed with 5 b...

Strontium-90 is a major hazardous contaminant of radioactive wastewater and its processing sludges at many Department of Energy (DOE) facilities. In the past, such contaminated wastewater and sludge have been disposed in soil seepage pits, lagoons, or cribs often under highly perturbed alkaline conditions (pH > 12) where 90Sr solubility is low and its adsorption to surrounding soil is high. As ...

Contents 1. Introduction 2. Soil acidity and its indices 2.1. Actual acidity. 2.2. Potential acidity. 2.3. Cation (positive ion) exchange capacity and saturation with bases. 3. Natural reasons for increasing soil acidification 3.1. Leaching regime. 3.2. Soil-forming rocks and plants. 3.3. The distribution of acid soils. 4. The reasons for anthropogenic acidification of soils. The phenomenon of ...

Soil properties are important factors modifying metal bioavailability to ecological receptors. Twenty-one soils with a wide range of soil properties (USA; http://soils.usda.gov/technical/classification/taxonomy/) were amended with a single concentration of Pb (2,000 mg/kg) to determine the effects of soil properties on Pb bioavailability and toxicity to earthworms. Earthworm mortality ranged fr...

Cadmium (Cd) concentration in soil solution and its bioavailability is controlled by sorption-desorption reactions. The objective of this research was to compare Cd adsorption behavior in six calcareous and four acid soils. Soil samples were equilibrated with 0.01 M Ca(NO3)2 containing 25 to 3200 mg Cd L−1. Results showed that the tendency for adsorption was high at low Cd concentrations (0-400...

Soil cation exchange capacity (CEC) depends on the extent and negative charge density of surfaces of soil mineral and organic components. Soil water sorption also depends on the extent of such surfaces, giving thus way to significant relationships between CEC and hygroscopic moisture (HM) in many soils. In this work, we explored whether CEC could be accurately predicted from HM in agricultural ...