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.

In leached chernozems used in crop rotations with different amounts of plant residues for nine years, the following parameters have been determined: the changes in the contents of the total carbon and carbon and nitrogen from the readily hydrolyzable components of the soil organic matter: the labile humus, detritus, and mortmass. No significant differences in the content of C_org in the soil among the crop rotations have been found. The different inputs of plant residues have significantly affected the contents of carbon and nitrogen in the readily mineralizable soil organic matter. The decrease in the mean annual input of the aboveground plant residues to the soil from 1.5 to 0.2 t C/ha resulted in the reduction of the carbon and nitrogen contents in the soil by 19–25% for the labile humus, 24–28% for the detritus, and 33–36% for the mortmass. The labile humus formed the largest fraction (3890 mg of C/kg soil or 10.3% of C_org on the average for the crop rotations); the fractions of the detritus (1546 mg C/kg soil or 10.3%) and mortmass (627 mg C/kg soil or 1.7% of C_org) were the next.

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.

Rapidly changing permafrost landscapes are a potential key terrestrial source of greenhouse gases (GHGs) at a global scale, yet, remain poorly characterized regarding GHG origins and environmental controls on emissions. Subsurface ice wedges, commonly found across many permafrost landscapes, harbor GHG‐rich gas bubbles. Analyzing these bubbles aids comprehension of subzero temperature GHG formation in permafrost. The Batagay megaslump, Earth's largest known thaw slump in northern Yakutia, provides an opportunity to study mixing ratios and isotopic compositions of both GHGs and non‐GHG in ice wedge samples from two stratigraphic units: the Upper Ice Complex (UIC) and the Lower Ice Complex (LIC). The Ar/N₂/O₂ compositions and bubble shapes indicated that the studied ice wedges were likely formed through dry snow and/or hoarfrost compaction, and microbial activity remained active after ice wedge formation. The high CO₂ and CH₄ mixing ratios and carbon stable isotope values suggested that CO₂ and CH₄ primarily originated from microbial sources. N₂O showed an “exclusive relation” with CH₄—meaning that high N₂O is observed only when CH₄ is low, and vice versa—and N₂O mixing ratios vary at different depths. These findings suggest that GHG formation in ice wedges is not solely controlled by physiochemical conditions, but involves a complex interplay between microbial activity and environmental conditions. Our study contributes to a better understanding of the dynamics involved in GHG formation within degrading permafrost landscapes.

This article is devoted to the study of the distribution of ground ice volumes in the upper layers of 5–10 m permafrost in the permafrost landscapes of Arctic Yakutia. Compilation of such a map will serve as a basis for assessing the vulnerability of permafrost to global warming, anthropogenic impact and forecasting the evolution of permafrost landscapes. The map was compiled using ArcGIS software, which supports attribute table mapping. The ground ice map of Arctic Yakutian permafrost landscapes shows that about 19% of the area is occupied by ultra ice-rich (above 0.6 in volumetric ice content) sediments. Very high ice volumes (0.4–0.6) are cover approximately 27%, moderate ice volumes (0.2–0.4)—25% of the area, and low ice volumes (less than 0.2)—about 29% of Arctic Yakutia.