On the Transformation of Chemical Composition of Seawater in the Interaction with Terrigenous Aerosols
Transformation of chemical composition of seawater during the interaction with loesses, an analogue of the natural terrigenous aerosols of the Pleistocene, was experimentally studied. It was shown that as a result of this process, change in the concentrations of major ions (K, Ca, SO4, HCO3), nutrients (Si, P), and fluorine occurs, while change in the content of chlorides, sodium, and magnesium was not detected due to their high concentrations in seawater. With increase in the mass content of solid phase, concentrations of sulfates and bicarbonates increase, and potassium concentration decreases. Concentrations of calcium and fluorine either increase or decrease depending on the content of mobile forms of these elements in the samples. The input of silicon and phosphorus into seawater has asymptotic limit: 2.5–3.3 mg Si/l and 0.012–0.040 mg P/l. The relationship between change in the concentrations of studied components in seawater and the mass content of solid phase corresponds to hyperbolic function, but at relatively small mass content it is described by linear equation in which the angular coefficient value is directly proportional to concentration of the component in water extract from this sample of loess. Change in the composition of seawater during the interaction with loesses can be predicted by the composition of their water extracts.