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Information on different compounds of elements, such as Na, K, Ca, Mg, Al, Fe, and Mn, contributes to our understanding of the genesis of poorly studied soils of northern coasts. The analysis has been carried out of the composition of various forms of compounds. To determine total element contents, a mixture of concentrated HF, HClO4, and HCl was used; acid-soluble forms were extracted with a mixture of concentrated HNO3 and H2O2; and acetate ammonium buffer solution was used to determine mobile forms. It is shown that the amount elements added to the tidal marsh zone is largely determined by the volume and composition of solids entering with seawater and with runoff from coastal catchments. For mineral soil horizons, a close correlation is found between the contents of clay fraction and exchangeable forms of K, Mg, and Al (R2 = 0.4–0.5), as well as between the contents of clay and highly mobile forms of these elements and Fe (R2 = 0.6–0.8). The distribution of elements along the profile of zonal soils on the highest positions of the relief is significantly influenced by the permafrost conditions and the aerial transfer of salts with seawater drops. [ABSTRACT FROM AUTHOR]

The research was conducted in the European northeast of Russia (Komi Republic), in the reclaimed quarries for mining construction sand in the middle taiga subzone, in the course of two decades after the forest reclamation (Pinus sylvestris) had been applied. The specific features of initial pedogenesis on substrates of different textures have been revealed. On sands and sandy loams, the dynamic soil sequence is composed by abralith (the 0-moment) → residual-calcareous humus psammozem (11th yr) → humus-raw-humus residual-calcareous podzolized humus gleyic psammozem (18th yr). On the loamy substrate, the following soil sequence is formed: abralith → humus residual-calcareous pelozem (3rd and 11th yr) → humus-raw-humus residual-calcareous eluviated gleyic pelozem (the 18th year). The formation of litter and humus-accumulative horizons are the leading soil forming processes. Their intensity is determined by the degree of plant community development. By the end of the second decade, the humus-accumulative horizon (0–20 cm thick) of sandy loamy soils accumulates up to 2.7 t/ha of organic carbon. Organic carbon pool in loamy soils reaches 6.3 t/ha. The stocks of soil nitrogen reach 0.1 and 0.4 t/ha, respectively. The rate of organic carbon accumulation in soil reaches 0.16 (sandy-loamy substrates) and 0.37 t/ha per year (loamy substrates). The organic matter of humus-accumulative horizons in the young soils of quarries is characterized by a higher content of water-soluble and labile components of humus and a low degree of condensation of humic acids as compared to the background soils. Initial pedogenesis on quarry substrata is characterized by an increase in the acidity of soil water extracts from pH 8.0 in abralith to pH 6.3–6.7 in the W horizon of the forming soils. The rate of acidification in loamy soils is lower than in sandy and sandy loamy soils. Carbonate leaching is confirmed by the absence of calcite and dolomite in the mineral composition of the upper W horizons of the forming soils, a decrease in the total content of calcium oxide from 4% in abralith to 2–3% in the W soil horizon and in the content of calcium carbonates (3 and <0.5%, respectively). In 18 years, weakly expressed features of eluviation, illuviation, and gleying appeared in the soil profiles. [ABSTRACT FROM AUTHOR]