The history of permafrost landscape map compilation is related to the study of ecological problems with permafrost. Permafrost-landscape studies are now widely used in geocryological mapping. Permafrost-landscape classifications and mapping are necessary for studying the trends in development of the natural environment in northern and high-altitude permafrost regions. The cryogenic factor in the permafrost zone plays a leading role in the differentiation of landscapes, so it must be considered during classification construction. In this study, a map's special content was developed using publications about Yakutian nature, archive sources from academic institutes, the interpretation of satellite images, and special field studies. Overlays of 20 types of terrain, identified by geological and geomorphological features, and 36 types of plant groupings, allowed the systematization of permafrost temperature and active layer thickness in 145 landscape units with relatively homogeneous permafrost-landscape conditions in the Sakha (Yakutia) Republic. This map serves as a basis for applied thematic maps related to the assessment and forecast of permafrost changes during climate warming and anthropogenic impacts.

The objective of this review is to present the results on the production techniques, process parameters and compositions of heat-resistant coatings for graphite and carbon-carbon composites. The data reported concern the resistance of such protective coatings in air at temperatures up to 2273 K and in the high-speed flows of oxidizing gas media taking place in the spacecraft equipment. Coatings of this type, generally, have a multilayer structure based on the refractory compounds such as carbides, borides, silicides of transition metals and oxides with a high melting temperature. An efficient heat-resistant coating for carbon-based materials should be composed of three layers from which each fulfills its own function. The paper presents a new complex method for formation of heat-resistant coatings on the carbon-based materials. The method combines the vacuum-activated diffusion saturation in the presence of a liquid-phase and self-propagating high-temperature synthesis (SHS) simultaneously. * Corresponding author. V. I. Zmij et al. 880 ical impacts, ablation and electroerosion.However, under conditions of high temperatures, even above 773 K, C/C composites reveal comparatively low oxidation resistance, which restricts to a great extent their wide application in different fields, particularly, in the high-temperature equipment.At present, the problems of effective protection for carbon-based materials, being under conditions of different oxidizing media, are comprehensively discussed in the literature. A current state of this problem is under consideration in the review article [1]. The effective protection of C/C composites against oxidation can be provided with taking into account the following: use of such materials as oxides, carbides, nitrides, borides, silicides and their various compounds; deposition methods and conditions; thickness and crack resistance of coatings; material designing limiting because of the chemical activity of material reinforcement components; new approaches to the choice of a heat-resistant coating material. Main requirements to the carbon composites are: atmospheric oxidation resistance, thermal impact resistance, humidity resistance, and high mechanical strength. The methods of carbon-based material stabilization are based on different approaches: multilayer coating deposition, formation of glass-forming or metallic coatings subjected to chemical transformations by thermal treatment, and glass-forming compound impregnation. In the above-mentioned review, one offers to use for carbon-based material protection the refraction metals such as W

The most massive and fast-eroding thaw slump of the Northern Hemisphere located in the Yana Uplands of Northern Yakutia was investigated to assess in detail the cryogenic inventory and carbon pools of two distinctive Ice Complex stratigraphic units and the uppermost cover deposits. Differentiating into modern and Holocene near-surface layers (active layer and shielding layer), highest total carbon contents were found in the active layer (18.72 kg m−2), while the shielding layer yielded a much lower carbon content of 1.81 kg m−2. The late Pleistocene upper Ice Complex contained 10.34 kg m−2 total carbon, and the mid-Pleistocene lower Ice Complex 17.66 kg m−2. The proportion of organic carbon from total carbon content is well above 70% in all studied units with 94% in the active layer, 73% in the shielding layer, 83% in the upper Ice Complex and 79% in the lower Ice Complex. Inorganic carbon is low in the overall structure of the deposits.

The most massive and fast-eroding thaw slump of the Northern Hemisphere located in the Yana uplands of northern Yakutia was investigated to assess in detail the cryogenic inventory and carbon pools of two distinctive Ice Complex stratigraphic units and the uppermost cover deposits. Differentiating into modern and Holocene near-surface layers (active layer and shielding layer), highest total carbon contents were found in the active layer (18.7 kg m-2), while the shielding layer yielded much lower carbon content of 1.8 kg m-2. The late Pleistocene upper Ice Complex contained 10.4 kg m-2 total carbon, and the mid-Pleistocene lower Ice Complex 17.7 kg m-2. The proportion of organic carbon from total carbon content is well above 70% in all studied units with 94 % in the active layer, 73% in the shielding layer, 83% in the upper Ice Complex and 79% in the lower Ice Complex. Inorganic carbon is low in the overall structure of the deposits.

Relationship between chernozem respiration and soil organic matter composition in the central forest-steppe of Western Siberia The aim of this work was to identify the relationship between the total loss of carbon in the form of CO 2 and fractions of easily mineralized soil organic matter (labile carbon, mortmass carbon, detritus carbon) by solving regression equations. It Взаимосвязи дыхания чернозема с соcтавом органического вещества почвы