Cation exchange capacity , organic

Methyl parathion is only slightly soluble in pH 7 water (55-60 ppm). This affects its mobility in water and its ability to be leached or solubilized into the water phase of a soil-water system. Factors most likely to affect the adsorption of methyl parathion in soil are organic matter content and cation exchange capacity. In soils of low organic matter (e.g., subsurface soils), calcium concentration, which affects the hardness of the water, may also be important (Reddy and Gambrell 1987). Several studies have shown... 

The main parameters that affect the cost-effectiveness of soil washing include the physicochemical parameters of the soil (grain size distribution, cation exchange capacity, percentage of silt, clay, or organic matter), and the type and concentration of contaminants. 

Almost all models can simulate organic, inorganic and metal fate, assuming that a careful calibration via an adsorption coefficient may alter the model output to predict measured/monitored values. However, not all models have by design increased chemistry capabilities (e.g., cation exchange capacity complexation), therefore, the most representative capabilities are indicated. 

Lead may be taken up in edible plants from the soil via the root system, by direct foliar uptake and translocation within the plant, and by surface deposition of particulate matter. The amount of lead in soil that is bioavailable to a vegetable plant depends on factors such as cation exchange capacity, pH, amount of organic matter present, soil moisture content, and the type of amendments added to the soil. Back-... 

Soils were further characterized by the determination of pH in water and potassium chloride in the proportions 1 2.5, total organic carbon (TOC) and cation exchange capacity (CEC). Transfer coefficients between soil and plant and enrichment in soils were determined. The results for Pb were represented in the form of relative enrichments for soils (Kabata-Pendias, 1985) and transfer coefficients in plants (Kovalevskii, 1979). 

Org. carbon - Organic carbon CEC cations exchange capacity... 

Heavy metals in rice and soils as well as several physicochemical indicators of soils including Organic matter (OM), pH, Cation- Exchange Capacity (CEC) and soil granularity were analyzed. As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Se, Zn and OM of soils, and As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Se and Zn of rice were determined at the central chemical lab of the Institute of Geophysical and Geochemical Exploration. The CEC of the soils was measured at the analytical institute of... 

The sorption behavior of 11 PAH compounds (a training set, Table 11) on various solid phases (e.g., three soils and two sediments) with different properties to relevant sorption (e.g., organic carbon content, clay content, pH, cation exchange capacity CEC Table 12), was determined by batch equilibrium studies [1]. Batch equilibrium tests were designed to determine rates of equilibrium sorption under conditions of high mixing and high surface areas of the solid particles (see Chap. 3). 

Also, the changes in pH will cause changes in the charges of variable-charge clays and organic matter, thus the cation exchange capacity of acid soils will tend to increase and that of alkaline soils decrease. 

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