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The formation of soils on loamy deposits during the primary succession of vegetation after biological reclamation of a technogenically disturbed area (quarry) in the middle taiga subzone of the northeast of European Russia (Komi Republic) is considered. The planting of Picea obovata on the reclaimed area activates the formation of the tree layer and helps to accelerate pedogenetic processes. In drained conditions, by the beginning of the third decade of succession, litter horizons were formed, soil bulk density in the upper mineral horizons decreased, and a tendency towards redistribution and differentiation of the clay fraction and iron and aluminum compounds in the soil profile was noted. The latter may indicate the beginning of eluviation. The heterogeneity of the quarry surface (presence of highs and lows with a height difference of up to 2–6 m) contributes to the redistribution of moisture within the quarry and the appearance of areas with surface waterlogging. Under these conditions, the role of conservation of organic residues (peat formation) is enhanced, and gleyzation processes are activated. With an increase in the degree of surface waterlogging of soils, the soil acidity and the stocks of soil carbon and nitrogen increase, which is typical for an analogous series of background soils. The calculated rate of organic carbon accumulation in the soil layer of 0–20 cm in drained soils of the quarry is about 0.4 t/ha per year. In the waterlogged soils, it increases to 1.0–1.2 t/ha per year. The stocks of organic carbon in the upper 20 cm of the profile of young soils remain two–four times lower in comparison with the background native soils. [ABSTRACT FROM AUTHOR]

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]

Concentrations of total carbon and nitrogen were measured by gas chromatography method, and the carbon content of inorganic compounds was determined by the volumetric method in soils of undisturbed coastal landscapes of the Barents Sea (Khaypudyrskaya Bay). Two groups of soils were specified. The first group included saline marsh soils formed under flooding by tidewater and surging seawater. The second group included soils of tundra ecosystems, which were subjected to precipitation of marine aerosols. In the first group, the content of Corg varied from 5 to 75 g/kg, the content of N total varied from 1 to 5 g/kg, and the Corg/Ntot ratio varied from 10 to 18. Humus-accumulative horizons buried under recent marine sediments were described in the middle part of the marsh soil profile. In the second group, the contents of Corg was 430–470 g/kg and Ntot 4–7 g/kg. The Corg/Ntot ratio in the surface peat horizons equaled to 64–95 g/kg and decreased by three–seven times in the deeper layers. The soils of the low-level marshes flooded each tide and especially their surface horizons contained more inorganic carbon than any other soils. Mass fraction of inorganic carbon varied from 4 to 20% of the total carbon content. Seawater and carbonate-containing rocks could be the source of the inorganic carbon. A correlation was found between the contents of Corg and Ntot in soils and in plant communities growing on these soils. Additional input of Corg and Ntot into marsh soils was due to the living activity of birds and to organic substances in seawater. [ABSTRACT FROM AUTHOR]