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Paleogeographic reconstruction of the West Siberian basin during the Jurassic is based on a variety of criteria used to evaluate the depositional environments (paleontological, sedimentological, geochemical, etc.). Extensive geochemical data on the hydrocarbon biomarkers in bitumen from organic matter are first used to constrain the depositional setting of this large region over a span of about 45 Myr. The study provides a detailed description of paleogeographic maps compiled for the main epochs of the Jurassic period with the reconstruction of paleorelief and differentiation of potential external and internal sources of terrigenous material. The paleogeographic reconstructions of the basin are considered with implications for the formation of regional seals and reservoir units. A special emphasis is given to interpretation of organic matter type and depositional setting of the major oil and gas source rocks. The study infers a paleogeographic control on the stratigraphic and areal distribution of hydrocarbon accumulations in the basin.

Studies of the paleontology and stratigraphy of the Triassic strata from the Lena-Olenek interfluve area and Kotelny Island have important implications for improving the accuracy of interregional and global correlations, refining the Boreal standard and international stratigraphic scale for the Triassic System. The importance of this study is also underlined by the necessity of refining the stratigraphic basis for regional geological exploration in Artic zone that now became the focus for building the country’s strategic resource base. Analysis of recent paleontological and stratigraphic data from key Triassic sections in the Laptev Sea coastal region provides new age constraints for the Triassic strata based on different faunal groups. The Triassic stratigraphic scheme for the region has been refined using new data on the paleontology, thickness variations, and boundaries of local stratigraphic subdivisions.

The particularities of the current tectonic structure of the Russian part of the Arctic region are discussed with the division into the Barents–Kara and Laptev–Chukchi continental margins. We demonstrate new geological data for the key structures of the Arctic, which are analyzed with regard for new geophysical data (gravitational and magnetic), including first seismic tomography models for the Arctic. Special attention is given to the New Siberian Islands block, which includes the De Long Islands, where field work took place in 2011. Based on the analysis of the tectonic structure of key units, of new geological and geophysical information and our paleomagnetic data for these units, we considered a series of paleogeodynamic reconstructions for the arctic structures from Late Precambrian to Late Paleozoic. This paper develops the ideas of L.P. Zonenshain and L.M. Natapov over the Precambrian Arctida paleocontinent. We consider its evolution during the Late Precambrian and the entire Paleozoic and conclude that the blocks that parted in the Late Precambrian (Svalbard, Kara, New Siberian, etc.) formed a Late Paleozoic subcontinent, Arctida II, which again “sutured” the continental masses of Laurentia, Siberia, and Baltica, this time, within Pangea.

Based on the analysis of various geophysical data, namely, free-air gravity anomalies, magnetic anomalies, upper mantle seismic tomography images, and topography/bathymetry maps, we single out the major structural elements in the Circum Arctic and present the reconstruction of their locations during the past 200 Myr. The configuration of the magnetic-field patterns allows revealing an isometric block, which covers the Alfa-Mendeleev Ridges and surrounding areas. This block of presumably continental origin is the remnant part of the Arctida Plate, which was the major tectonic element in the Arctic region in Mesozoic time. We believe that the subduction along the Anyui suture in the period from 200 to 120 Ma caused rotation of the Arctida Plate, which, in turn, led to the simultaneous closure of the South Anyui Ocean and opening of the Canadian Basin. The rotation of this plate is responsible for extension processes in West Siberia and the northward displacement of Novaya Zemlya relative to the Ural–Taimyr orogenic belt. The cratonic-type North American, Greenland, and European Plates were united before 130 Ma. At the later stages, first Greenland was detached from North America, which resulted in the Baffin Sea, and then Greenland was separated from the European Plate, which led to the opening of the northern segment of the Atlantic Ocean. The Cenozoic stage of opening of the Eurasian Basin and North Atlantic Ocean is unambiguously reconstructed based on linear magnetic anomalies. The counter-clockwise rotation of North America by an angle of ~15º with respect to Eurasia and the right lateral displacement to 200—250 km ensure an almost perfect fit of the contours of the deep-water basin in the North Atlantic and Arctic Oceans.

Results of laboratory modeling of the remediation of waste product containing oil products (652 g/kg) and natural radionuclides (²²⁶Ra, ²³²Th и ⁴⁰K) by means of landfarming, biostimulation and bioaugmentation are presented. It is established that landfarming and biostimulation provide a decrease in oil product content and in the phytotoxicity of the waste product; landfarming is a more rapid process.

Phytomonitoring of atmospheric pollution was performed using Scotch pine as a highly sensitive bioindicator. Pine needle samples were collected in reference sites along the 320 km Sayansk-Irkutsk-Listvyanka transect passing through the major industrial centers of Baikal region and stretching to the shores of Lake Baikal. The concentrations of inorganic pollutants such as sulfur, fluorides, heavy metals etc. in needles were determined. The highest level of atmospheric pollution was detected at the territories of the Angarskiy, Irkutskiy, Usolskiy, Shelekhovskiy industrial centers, lower pollution is observed within the Sayan and Cheremkhovo industrial centers. The data show that the majority of pollutants reach the Baikal shore.

The anatomic-morphological indicators of the needles of Picea obovata Ledeb. under the effect of emissions from the industrial zone of Kemerovo were investigated. Some changes of the negative nature were detected: a reduction of length, area and the surface of pine needles, the thickness of the inner lining and epidermis, an increase in the asymmetry of the central conducting beam, a reduction of the number of pitch channels. Some changes of the adaptive nature were also detected: an increase in the thickness of epidermis and endodermis, an increase in the area of pitch channels and the central cylinder. The significant correlation of the complex index of atmospheric pollution with the anatomic-morphological characteristics of pine needles was revealed. This confirms the fact of the substantive effect of emissions from the industrial zone of Kemerovo on the anatomical structure of pine needles of Picea obovata Ledeb.

Evaluation of urban soil for Kirov as example was carried out by means of chemical analysis and biotesting. Total content and the concentrations of mobile forms of heavy metals (Zn, Cu, Cd, Ni, Fe, Pb), pH of water and salt extracts, humus content were determined in different regions of the Kirov city. On the basis of the total index of tecnogenic pollution (Z_c), urban soil is characterized by the low level of pollution. Test objects of different trophic groups were used for biotesting: Daphnia magna Straus , Paramecium caudatum, Escherichia coli. Results of the comparative analysis of the sensitivity of different biotesting methods are presented.

The six litter types, such as heavily decomposed, middle decomposed, rhizome-like (coarse decomposed), turfy, peaty and turf, were determined on the gradient of large grass-dead soil cover-sphagnum in the bog birch forest. Specificity of their biochemical transformation depends on the amount of gumic acid accumulation, mainly of the first fraction (GA-1), at the background of relatively uniform rate of the formation of fulvic acids. The intensity of GA-1 formation is closely positively connected with the biological activity of substratum, judging from the C/N ratio. However, unclear distinctions between these indices of forestry-morphological litter types limit their diagnostic reliability. Grouped biochemical litter categories – mild (heavilyand middle decomposed), transitional (rhizome-like, turfy, peaty) and coarse (mossy) are significantly discriminated by the C/N ratio – 20, 30, 40, as well as by the content of GA-1 – 14, 10, 6 %, respectively.

Incidence and intensity of bark stripping of trees by ungulates was investigated at no bamboo (Fargesia nitida (Mitford) Keng f. ex Yi) (B–) site and understory bamboo dominant (B+) site of a subalpine Abies faxoniana forest, southwest China. The percentage of damaged trees in B– site was higher than in B+ site. Bark stripping obviously occurred more frequently on Abies faxonian а Rehder & E. H. Wilson compared to other tree species. Appearance of stripped bark and dead stems of the trees in different size-classes of A. faxoniana strongly depended on the density of dwarf bamboo at the site, and also on the size and bark structure of the trees, with highest damage rates occurring on the smaller DBH classes (10–40 cm) in B– site. The bark stripping intensity of A. faxonian а decreased significantly with higher density and coverage of F. nitida around damaged trees. Therefore, there is an indirect negative effect of the distribution of dwarf bamboo, F. nitida , on bark stripping of tree species. We suggest the indirect effects of dwarf bamboo species should be taken into account while considering the succession and regeneration of natural forests.