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Analysis is given to data on the chemical and mineral compositions of Archean-Early Paleozoic metamorphic carbonate rocks of greenschist to granulite facies. A continuous series of pure carbonate to nearly carbonate-free rocks derived from a calcium-enriched sedimentary protolith has been revealed. Several groups of metacarbonate rocks (petrotypes) with statistically significant boundaries between them have been recognized. The boundaries are used as a basis for a systematic scheme of metacarbonate rock nomenclature proposed by the Subcomission on the Systematics of Metamorphic Rocks (SCMR), a branch of the Commission on Systematics in Petrology (CSP) of the International Union of Geological Sciences (IUGS).

Petrochemical study of metabasites from the Uimon Zone, Gorny Altai, shows essential differences in TiO₂, MgO, Na₂O, K₂O, and P2O5 contents between glaucophane-bearing, winchite-actinolite, and actinolite schists. Geochemical discrimination of these rocks suggests that blueschists are comparable to alkaline basalts of oceanic islands (OIB), whereas greenschists correspond in composition to tholeiite basalts of N-MORB type and their tuffs. Mineralogical distinctions of the rocks (namely, the presence of glaucophane or actinolite) are stipulated by chemical compositions of their protoliths, instead of variations in P-T conditions of metamorphism. Under similar P-T conditions (350-400

The Ozernoe hydrothermal-sedimentary pyrite-polymetallic deposit in western Transbaikalia abounds in Fe-Mg-carbonates (predominantly siderites), which make up two major genetic groups of siderite ores: hydrothermal-sedimentary ores and their varieties recrystallized during hydrothermal-metasomatic processes. These groups of ores differ in structure, morphology, mineralogy, and geochemistry. Hydrothermal-sedimentary siderite ores form sheet bodies, make up ore sulfide-siderite rhythmites, have a fine-grained texture, and are polymineral siliceous-sulfide-carbonate formations. Siderites of these ores are Zn-enriched. Recrystallized ore varieties form deposits of complex morphology along the southeastern limb of the Ozernoe syncline on the flanks of silicic-alkaline metasomatites. These ores occur at different stratigraphic levels and coexist with stratified bodies of sulfide and sulfide-siderite ores. Exo- and endocontact zones of siderite deposits abound in coarse-crystalline siderite-barite-sulfide ores.
The isotopic compositions of carbon and oxygen of siderites, ankerites, and dolomites of hydrothermal-sedimentary ores and chemogenic and reef limestones of the ore-bearing section are generally the same as the isotopic compositions of coeval marine carbonates: δ¹³C = -1.6...+2.0<194> and δ¹⁸O = +15...+22<194>. Carbon plays a minor role in the formation of hydrothermal-sedimentary ores. Siderite varieties produced through recrystallization of sedimentary siderites during superposed metasomatic processes inherit the isotopic composition of their predecessors. Great variations in isotopic compositions of carbon and oxygen are observed within the large Ozernoe-Vasil'evskoe ore-bearing structure enclosing the Ozernoe deposit. The isotopic compositions of carbon and oxygen in carbonates of ores and ore-hosting rocks of this structure become heavier from base to roof of its section. The isotopic composition trends of carbon and oxygen are similar in behavior to that of sulfur in ore sulfides. Carbonates of hydrothermal-sedimentary iron oxide ores associated with sulfide ores have significantly lighter isotopic compositions of carbon (-0.5...-5 ‰) and oxygen (-2...+5 ‰). It is shown that the isotopic compositions of carbon and oxygen depend on the content of Mn in Fe-Mg-carbonates.

New paleomagnetic data have been obtained from the Neoproterozoic subvolcanic intrusions which are widespread in the Biryusa terrane of the southwestern margin of the Siberian craton. The mafic dike swarms called the Nersa complex are rift-related subvolcanics, which could be used as indicators of the initial stage of the Neoproterozoic breakup of the Rodinia supercontinent. Two stable components of magnetization from the Nersa intrusions and Neoproterozoic sedimentary rocks of the Karagas Group were obtained. One of them is possibly a synfolding component related to the Early Paleozoic deformation processes. The other is the characteristic component of remanent magnetization, with the site-mean direction characterized by D _s = 146.4, I _s = 11.0, and α₉₅ =13.3}>. The nature of this component is disputable. On the one hand, it can locate Siberia in the Late Neoproterozoic, but on the other hand, it also can reflect the Early Paleozoic remagnetization processes. Detailed analysis of the data, including results of reversal, baked-contact, and fold tests, suggests that the paleomagnetic directions could be of primary origin. We have tested the new paleomagnetic pole for its correspondence to some alternative tectonic reconstructions of Rodinia and believe that Siberia had an equatorial position and its modern southern margin was oriented to Laurentia during Neoproterozoic time.

Conditions of unstable equilibrium of single-layer islands of the adsorbate and empty adsorption vacancies are studied. An analog of the Kelvin–Thomson effect for these islands is found. Appropriate corrections are made in the classical theory of nucleation.

The changes in the composition and the projective cover of understory species and regeneration after fires in 1996 and 2002 in pseudotaiga larch forests of the Central Khangai, Mongolia have been investigated. Descriptions of vegetation and inventory of natural regeneration were carried out in 2007, 2010 and 2012 on permanent sample plots that were established in each of two sites. According to the Detrended Correspondence Analysis (DCA), no drastic changes were observed in species composition of the plant community during 11, 14, 16 years after fire of 1996 and 8, 10 years after fire of 2002. Regarding the plant cover, remarkable change was not observed in vegetation, except in 5 year-old stand. Grasses-herbs community with young larch saplings 10 years after fire of 2002 was formed. Loose herbs community with young larch saplings 16 years after fire of 1996 was established. Moreover plant life forms were identified during the succession years post-fire. By Christen C. Raunkiær life form classification (1937), life forms such as cryptophytes and hemicryptophytes either kept or shared their dominant position following fire. These plants seem to be fire-resistant and have a high ability to recover post-fire. After the fires, natural regeneration was successful. However, grazing may affect negatively to larch regeneration. It can be explained by difference of large saplings in two plots. The number of large saplings per hectare was low despite the long recovery period in one plot.

Anthropogenic pollution of boreal forests by polycyclic aromatic hydrocarbons was assessed by polycyclic aromatic hydrocarbon (PAH) concentrations in needles of Scots pine (Pinus sylvestris L.) trees growing in the vicinity of the Bratsk aluminium smelter - one of the largest aluminium smelters in the world. The fieldwork was performed in 2012-2013 on 34 index plots, set in mixed herb and sedge-mixed herb pine forests (mostly site class III). It is shown that the total accumulation of PAHs reaches its highest level (more than 6000 ng/g) in pine needle samples collected at sites up to 3 km from the aluminium smelter. PAH total quantity decreases with increasing the distance from the pollution source and at a distance of 50 km reaches values close to background ones. The highest concentrations of PAHs were detected in needle samples collected at plots located from the plant in a direction corresponding to the prevailing emissions transfer. There was also detected a significant difference in compositions of individual PAHs: there were 18 compounds identified in samples collected near the aluminium smelter whereas only 6 compounds were identified in samples collected on the background territories. Among the PAHs accumulated in pine trees assimilation organs the substances with 3-4 aromatic rings (phenanthrene, fluoranthene, pyrene, chrysene) were dominant with their total number reaching 90 % of the total. Compound with 5-6 aromatic rings (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[e]pyrene, perylene, indeno[1,2,3-c,d]pyrene, benzo[g, h, i]perylene, dibenz[a, h]anthracene).comprises a smaller proportion (from 6 to 27 %) in total PAHs content. High concentrations of benzo[a]pyrene and perylene in needle samples collected in the vicinity of the aluminum smelter indicate technogenic character of forest pollution.

The Siberian larch (Larix sibirica Ledeb.) is the main forest genus in Siberia and Mongolia. The systematization of Siberian larch is based on morphological diversity, so the study of morphological features variability is actual for selecting and foresting of this forest genus. Analysis of variability of cones’ morphological features for Siberian larch have been carried out. The morphological features variability for more than thirty coenopopulations in different vegetation conditions have been investigated. The basic laws of larch features differentiation in mountain regions Mongolian and Russian Altai and Khangai have been revealed. The main factors, deciding the variability of cones morphological features are exposure, elevation and exposition of mountainside. The intrapopulation variability of cone morphological features increases with increasing elevation of the coenopopulation above sea level. The highest values of metric features of cones have been found in more moist northern and north-eastern flanks of the Altai and Khangai. The trees with rounded form of seed scale have been most common in the populations structure of Siberian larch. However, the increase of the occurrence of trees with a straight and notched form of seed scale edge has been observed with increasing elevation of the population above the sea level. Apparently, the increase of the occurrence of trees with a straight and notched form of seed scale edge is not typical for this genus larch shows that these features are revealed in extreme environmental conditions.

The paper analyzes the scientific achievements and heritage of Alexey Ivanovich Buzykin, a well-known Siberian forest researcher, the Honored Forester of the Russian Federation, who contributed remarkably to improve the knowledge of the forests of Siberia. He was the first to explore the possibility to increase Siberian forest productivity by its scientifically justified regulation. He accurately estimated forest productivity responses to increasing soil nitrogen using a large amount of data, studied structural, species composition, and density changes that occur in young mixed stands after tending felling, revealed stand productivity dependence on stand density, and showed how structure and dynamics of forest generations are manifested through vegetation succession. Along with studies of natural ecosystems, Alexey I. Buzykin did large-scale experiments on managing forest ecosystems by different types of sanitary cutting, application of fertilizers to soil, regulation of cold soil thermal regime, and by establishment of Scots pine, spruce and larch plantations covering a range of stand densities. To achieve his forest management objectives, he developed original forest research methods, among them methodologies to assess seedling and sapling amounts, to estimate forest response to fertilizer application, and to classify young forest stands by formation type. He also developed tables of small-sized young tree trunk volumes. During his last years, Alexey I. Buzykin, in collaboration with other researchers, accomplished a series of theoretical studies. He suggested that mathematical tools should be used for interpreting different kinds of events and changes occurring in forest ecosystems including the use of phenomenological models of stand establishment processes, stand growth models, forest succession models, and other models. The results of Alexey I. Buzykin’s research studies are still very important regarding large-scale forestry activities. They have been used for many years to improve forest management practices in Siberia and have been considered in the forest use normative documents of the federal level. A list of Alexey I. Buzykin’s major research works concludes the paper.

The analysis of scientific achievements and scientific heritage of the oldest Siberian forester and introducer - Reginald Ivanovich Loskutov, who has made a significant contribution to the technology of growing conifers in Siberia, and list of his major scientific publications is presented in the article. It is noted that proved particularly fruitful activity of Reginald I. Loskutov in the introduction of woody plants, and in the creation of the Arboretum of V. N. Sukachev Institute of Forest, Russian Academy of Sciences, Siberian Branch and decorative renovation of urban green spaces in the city of Krasnoyarsk. For 38 years Reginald I. Loskutov tested about 450 species, varieties and forms of unique ornamental trees and shrubs. Now in the collections of the Arboretum successfully grow more than 260 species, varieties and forms of plants belonging to 75 genera and 28 families. Reginald I. Loskutov and academician Igor Yu. Koropachinsky tested basic range of woody plants of different botanical and geographical areas of the world, numbering nearly 250 species recommended for cultivation in the city of Krasnoyarsk and its related climate areas of southern Siberia.