Geochemistry of carbonatic/sulphatic soils in the southern Angara region, Russia

The geochemistry of carbonatic/sulphatic soils of the southern Angara region is distinguished for its uniqueness as regards macro-as well as microelements. According to contents of some elements, the territory represents a contrasting positive geochemical anomaly: the soils are enriched above the average concentration (hereinafter referred to as Clarke) in Ca, S, Cl, P, Sr, Zn and Cu. But according to contents of many other elements, such as Rb, K, Ba, Cr, Ga, Zr, Ti and Pb, including lanthanides (Y, La, Ce, Pr and Nd), it is the territory of negative anomaly. Gleyic solonchaks are particularly strongly depleted, perhaps due to leaching the elements. Soils develop peculiar bonds between elements. Strong enrichment in P and Sr depends on sulfur accumulation in soils. Potassium depletion is accounted for by a deficiency of alumosilicates. Ba content decreases with an increase in the amount of calcium in the soil. The content of lanthanides depends directly on the amount of alumosilicates and indirectly on the content of carbonates. There is a difference in the geochemistry of separate lanthanides. A deficiency of chromium is particularly clearly pronounced in gleyic solonchak. A deficiency of zirconium is accounted for by a shortage of its main carrier, i.e. titanium, the content of which in soils is below a Clarke.