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Data on postpyrogenic dynamics of soils under mountainous taiga cedar (Pinus sibirica) and pine (Pinus sylvestris) forests and subtaiga–forest-steppe pine (Pinus sylvestris) forests in the Baikal region are analyzed. Ground litter–humus fires predominating in this region transform the upper diagnostic organic soil horizons and lead to the formation of new pyrogenic organic horizons (Opir). Adverse effects of ground fires on the stock, fractional composition, and water-physical properties of forest litters are shown. Some quantitative parameters of the liquid and solid surface runoff in burnt areas related to the slope gradient, fire intensity, and the time passed after the fire are presented. Pyrogenic destruction of forest ecosystems inevitably induces the degradation of mountainous soils, whose restoration after fires takes tens of years. The products of soil erosion from the burnt out areas complicate the current situation with the pollution of coastal waters of Lake Baikal.

The stabilities of the humus in different soil types (a soddy-podzolic soil from Moscow oblast, a deep typical chernozem from Kursk oblast, and a typical sierozem) have been compared on the basis of long-term studies of the composition, structural features, and properties of the humus acids formed under contrasting climatic conditions. The transformation features of the humic substances under agrogenic impacts of different intensities and durations have been studied by the example of a soddy-podzolic soil as a soil susceptible to environmental changes. The features of degradation of the humus quality and their manifestation at different levels of the structural organization of the humus system have been characterized.

Specific features of the development of redox systems in the soils of coal mine dumps in Kemerovo oblast were studied. The quantitative characteristics of the fractional composition of the oxidized and reduced components in these soils were obtained, and their heterogeneity was shown. Distribution patterns of the reduced and oxidized components in the parent material of these specific technogenic landscapes in the course of soil evolution were revealed.

The results of long-term studies (1957–2007) of the changes in the morphology of soil profiles and in the reserves and fractional composition of the humus in the soils of the Ingulets irrigation system are discussed. After 50 years of irrigation, the boundaries of the genetic horizons shifted downward by 15–30 cm. The redistribution of the humus took place: its content decreased to a low level in the plow layer of the irrigated and rainfed soils and significantly increased in the layer of 60–100 cm so that the reserves of humus in the layer of 0–100 cm somewhat increased and corresponded to a moderate level. The distribution of humus in the soil profiles was characterized by the gradual lowering down the soil profile. The concentration of nitrogen in the humus of the irrigated southern chernozems was very low. The degree of humification of the soil organic matter was high. The humus was of the humate type in the upper horizons and of the fulvate-humate type in the lower horizons.

The total concentration and fractional composition of aluminum compounds were determined in soil solutions obtained using vacuum lysimeters from the main genetic horizons of peaty-podzolic-gleyic soils developed on binary deposits. The total concentration of aluminum in the brooks draining the area with a predominance of these soils was also estimated. The total aluminum concentration in the soil solutions reached the maximum values (0.079–0.092 mmol/l) in the Eih horizon and generally decreased down the profile. The aluminum in the soil solutions occurred in the form of monomeric inorganic and organic compounds and complexes with high-molecular-weight organic acids. The proportion of inorganic monomeric aluminum compounds in the solutions from the peaty-podzolic-gleyic soils increased compared to that in the podzolic soils; no aluminosilicate compounds were found. Aluminum arrived to the brooks draining the areas with the predominant peaty-podzolic-gleyic soils mainly from the above-moraine horizons, including the Eih, E, and Ecn. It was supposed that the removal of aluminum from these soils exceeded that from the podzolic soils.

The data on the fractional composition of the heavy metal (HM) compounds in the plow horizon of a loamy-sandy soddy-podzolic soil investigated by different methods of fractionation are presented. The use of the BCR (Community Reference Bureau) scheme did not fully allow revealing some regularities governing the state of the copper, zinc, nickel, and lead in the soil. This system does not reflect the existing ideas concerning the interaction between the HMs and soil components. The chemical properties of the elements are manifested more distinctly when the scheme of the HM fractionation elaborated in our country is used. Despite some disadvantages, the method of chemical fractionation of metal compounds permits one to obtain adequate and useful information on the state of the microelements and HMs in soils.

The study of the humus status of the buried soil sequence in loess deposits of the Minusinsk inter- montane trough revealed that the group humus composition and humus properties of the buried soils did not undergo considerable changes and preserved their initial parameters upon the burial under the conditions of low biological activity. Neither the group humus composition nor the humus substance properties fell beyond the limits typical of the humus status of recent soils. The fractional composition of the humus acids might undergo secondary alterations after the burial. The dependence between the humus type and the length of the biological activity period permitted us to make a paleoclimatic reconstruction of the bioclimatic conditions that might have existed during the formation of the loess deposits in the Minusinsk intermontane trough. It was shown that the soil-climatic zones were repeatedly alternating during the Quaternary period due to the global climate change.

The results of studying the dynamics of forest litter properties in the loci of a Siberian moth (Dendrolimus sibiricus) mass outbreak are considered. As a fir forest defoliated by this pest burns, the reserves and fractional composition of the forest litter, its actual acidity, and its chemical composition drastically change. Upon the burning out of such forests, the litter complex of invertebrates is fully destroyed and begins restoring only two years after the fire.

The formation mechanism of heavy metal fluxes migrating with the solid runoff of rivers and composing more than 90 wt % of the metals involved in the system of water migration was studied. The aggregation features of the finely dispersed soil components and the important role of humic acids in the formation of microaggregates were revealed. The particle-size compositions of the readily mobilizable microaggregates and river suspensions were determined and compared. On the basis of the comparative geographical study of the fractional composition of the humic acids from different soil types and the calculation of the metal weights in microaggregates, the effect of the HA1-to-HA3 fraction ratio on the structure of the metal fluxes was shown.