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We present data on the most complete Neogene sections and wells of northern Ustyurt and the Cis-Aral area. The Miocene deposits in the northern chinks and the North Ustyurt depression are composed of sediments of the Tarkhanian, Chokrakian, Karaganian, Konkian, and Sarmatian regional stages of the Eastern Paratethys, which are overlapped by lower Pontian beds. The distribution of thicknesses and facies shows that the North Ustyurt depression remained the main synclinal structure of the region, along which the waters of all Miocene transgressions were spread. Sandy material was brought by the rivers from the north: A sandy lens of Chokrakian age is traced along the Shomishtykol Sor almost to the axial part of the depression. Transgressions were pulsating, and the lower and middle Sarmatian deposits were most widespread. These data are presented as a geologic profile near Beineu Village and as schematic maps of facies for the middle Miocene regional stages.

The Tuva segment of the Central Asian Orogenic Belt is characterized by the ubiquitous presence of conglomerates few tens of meters to a kilometer in thickness in early Paleozoic volcanosedimentary sequences. We present the first results of geochemical, isotope-geochemical (Sm-Nd and Rb-Sr), and U-Pb geochronological studies of granitoid boulders and pebbles from the conglomerate sequence of the early Cambrian Bayan-Kol Formation of the Systyg-Khem depression. These studies made it possible to establish several sources of clastic material as a result of the destruction of granitoids of different ages and isotope-geochemical compositions. At least two complexes of granitoids were denuded in the pre-Ediacaran tectonic block in the early Cambrian: (1) middle Ediacaran (~590 Ma) and (2) early Ediacaran (~630 Ma); the latter resulted from the melting of pre-Ediacaran island arc crust formed from a depleted mantle source (εNd(T) = +8.0 to +8.6). At present, no granitoids of this age and with such isotope-geochemical characteristics have been found within the Tuva segment. Probably, the granitoid complexes reconstructed from the results of study of clastic conglomerates are eroded or buried beneath younger deposits and do not expose. Thus, the study of clastic conglomerates from the Bayan-Kol Formation provided the first information about the Precambrian history of the tectonic block whose destruction led to the accumulation of this terrigenous sequence.

The data inferred from a new key section in the basin of the Vilyuy river allowed us to examine the structural-faces features and absolute age of cross-layered sandy-loam sediments of the D’olkuminskaya series distributed in Central Yakutia in a wide hypsometric range. These deposits had formed in the period from the latest Kargin thermochron to the beginning of the Holocene (between 35 ka and 12-10 ka BP) under the overwhelming conditions of severe desiccation and desertification of the area. During the Boreal optimum of the Holocene, the soil-vegetation cover had largely provided for the stabilization of dune covers. The formation of the contemporary moving-dune massifs had taken place not more than one thousand years ago and had been directly linked with the climatic events of the Little Ice Age.

The study has been focused on the thermal regime of peat soils (fibrist histosols) of palsa bogs and peat plateaus in northern West Siberia. Autonomous loggers recorded temperature for 343 days every hour to a depth up to 60 cm in palsas and 120 cm in hollows (pools, lawns) in four mire ecosystems: the forest tundra hollow and palsa, and the northern taiga hollow and palsa. The data on the mean daily temperature, the mean annual temperature, the extremes, the annual amplitude, the active layer dynamics, the sums of positive and negative temperatures at different depths have been adduced. The established differences in the thermal regimes of soils were due to the differences in the ecosystems of mires, rather than in bioclimatic zones they belong to. The high-latitude mires have the largest impact on the annual amplitude and temperature parameters obtained for the cold period.

Long-term and seasonal variations in major- and trace-element compositions of groundwaters in anthropogenic cryopegs stripped by boreholes in unconsolidated alluvial sediments have been monitored for thirty years at a site within Yakutsk city. Suprapermafrost cryopegs became less saline for the past five to seven years as a result of climate change in many previous years. The obtained data on chemistry and flow dynamics of groundwaters indicate enhanced hydraulic connectivity of cryopegs in the active layer. The ongoing ground temperature warming will lead to general decrease in the contents of highly soluble salts in suprapermafrost cryopegs and to increase in trace element abundances in pore waters.

The paper presents the estimates of evident ground ice contained in the permafrost of the Tien Shan Mountains based on the available geocryological maps of various scales. The maps represent patterns of permafrost distribution reflected in the regional structures depending on geocryological zonality. Using the data on the areal extent, thickness and ice content of permafrost, the volumes of permafrost and ground ice have been determined. It has been revealed that the largest volumes of ground ice occur in active rock glaciers and recent moraines. The volume of glaciers relative to that of ground ice has been ascertained to decrease signifi cantly due to the glacial degradation.

The spatial distribution of soil СO2 efflux measured at Novyi Urengoy station in southern tundra (Taz Peninsula) is determined by the soil volumetric moisture content and water-extractable organic carbon and with elevations above sea level. The contents of soil water-extractable and microbial biomass carbon are highly variable over the territory. The spatial distribution of the soil microbial carbon content partly depends on organic layer thickness and soil moisture, which are responsible for 19 % and 8 % of its variance, respectively. The environmental factors of active layer thickness, soil volumetric moisture, and soil surface temperature are relatively stable as the soil and vegetation covers are homogeneous while the soil organic layer is thin.

Changes in the equilibrium line altitude (ELA) of glacier systems have been studied in the Suntar-Khayata, Chersky and Orulgan mountains, as well as over the whole territory of Northeastern Siberia, for three periods of time: 1930-1960, 1961-1990 and 1991-2012. Northeastern Siberia has undergone warming in the 21st century which became more rapid than in the previous fi fty years. Records at most weather stations show increasing trends in mean annual and summer air temperatures and in total atmospheric precipitation but a decreasing trend in solid precipitation. The climate change has led to a rise of glacier ELA almost all over the Northeastern Siberia and to an increase in ablation which is in balance with accumulation at this altitude. The ELA rise is from 100 to 450 mm, 200 ± 50 m on average, while the ablation (accumulation) increase is 50 to 250 mm in different periods. The glacier parameters inferred from climatic data are background values, which provide a general idea of current and potential changes in glacier systems in this poorly studied region.

The results of measurement of snow cover density for the period from 2005 to 2017. The data on snow density have been obtained during regular observations carried out on a stationary horizontal sites located in Yuzhno-Sakhalinsk and during field work. 227 snow pits have been sampled, and more than 2,000 values of snow density for different snow layers have been analyzed. Data on distribution of snow density in different landscapes have been compiled and structured. The maximum density of snow is typical for treeless regions with dominating strong winds. Typical densities for specific snow structure have been revealed. The density of snow layers have been found to vary depending on the type of snow in the range from 40 kg/m³ (newly fallen snow) up to 790 kg/m³ (ice crust).

A general characteristic is provided for the foreign and Russian ecological insurance market, and the institutional peculiarities of its formation are considered. Particular emphasis has been placed on a deficit of national normative legal acts serving as the «engine» of generation of off-budget funds by participating users of nature of the contemporary market economy. The Baikal region comprising three constituent entities of the Russian Federation (Irkutsk oblast, Republic of Buryatia, and Zabaikal’skii krai) is regarded as a model territory for analyzing a relatively recently emerging (for Russia) direction of the insurance market. The study revealed structural features (the relationship of the obligatory and voluntary sectors of ecological insurance), and the magnitude (the number of licensed insurance organizations, and the annual turnover) as well as the qualitative potential of the regional ecological insurance market. This market is represented by encompassing the main types of hazardous production facilities on the basis of the effective classification of ecological risks in the form of a table. We initiate the implementation of the regional law «On obligatory ecological insurance» (following the example of a number of other constituent entities), because the future prospects of development of the Baikal region are predetermined by the location of Lake Baikal on its territory, the drainage area of which has a special regime of nature management.