Denis V. Moiseev

Rapid Atlantification is altering primary productivity and benthic-pelagic coupling in the Eurasian Arctic. This study assessed sedimentary pigments as indicators of exported production in the poorly studied St. Anna Trough, a critical conduit between the Barents and Kara seas. Sediment samples were collected at 20 stations in autumn 2023, and phytopigment concentrations were analyzed spectrophotometrically alongside hydrological data. Multivariate analysis revealed two distinct benthic regimes separated by the Marginal Ice Frontal Zone. The southern sector, influenced by thick seasonal warm water masses (WWM) in the subsurface layer, exhibited mesotrophic conditions with mean chlorophyll-a + pheophytin-a concentrations of 30.28 ± 6.51 µg g⁻¹. The northern sector, dominated by Arctic-origin water masses, was oligotrophic (4.45 ± 0.54 µg g⁻¹). Redundancy analysis identified WWM thickness as the primary driver, explaining 60.5% of the total variance in pigment contents, followed by ice-cover duration (9.8% negative effect). Pigment indices and high pheophytin proportions indicated predominantly detrital organic matter, though stations near the Barents Sea inflow showed fresher material. The prevalence of chlorophyll-b in the north suggested ice-associated green algae, while chlorophyll-c dominated the diatom-rich southern inflow. These findings establish a crucial baseline for monitoring climate-driven shifts in pelagic-benthic coupling as sea ice retreat continues.

This study presents oceanographic observations from the R/V Dalnie Zelentsy along the Kola Section (2017–2023), focusing on the northern Polar Front during autumn, winter, and spring. Sea ice anomalies were estimated using data from the World Data Center for Sea Ice (AARI WDC Sea-Ice). Observational data near the Marginal Ice Zone were compared with temperature and salinity fields from global oceanographic datasets, including MERCATOR PSY4QV3R1, CMEMS GLORYS12v1, and TOPAZ5. High-gradient temperature and salinity zones were observed at varying distances from the ice edge along all sections. Over the past three decades, the western Barents Sea has experienced a steady decline in sea ice cover. The northernmost Polar Front along the Kola Section ranged from 48 to 290 km from the ice edge, with temperature gradients of 0.10–0.20 °C/km and salinity gradients of 0.012–0.025 psu/km. The frontal zone width did not exceed 55 km. Among the assessed data products, MERCATOR PSY- 4QV3R1 showed the highest correlation with in situ measurements.

The results of oceanographic observations conducted on board the R/V “Dalnie Zelentsy” along the Kola Section during 2017–2023 are presented. The main focus is on the assessment of frontal zone characteristics in the northern part of the Polar Front during autumn, winter, and spring periods. To estimate sea ice anomalies, data from the World Data Center for Sea Ice (AARI WDC Sea-Ice) were used. A comparison was made between observational data from the northern section near the Marginal Ice Zone and temperature and salinity characteristics from global oceanographic databases. The comparison involved products such as MERCATOR PSY4QV3R1, CMEMS GLORYS12v1, and TOPAZ5. High-gradient zones in temperature and salinity fields were identified along all sections at varying distances from the ice edge. It was confirmed that the western Barents Sea had experienced a steady trend of sea ice cover declining over the past three decades. The northernmost frontal zone of the Polar Front in the Barents Sea, along the Kola Section axis, detected at distances of 48 to 290 km from the ice edge. Temperature gradients ranged from 0.10 to 0.20 °C/km, salinity gradients varied from 0.012 to 0.025 psu/km, and the width of the frontal zone did not exceed 55 km. The best correlation with the measurement results was observed in for the MERCATOR PSY4QV3R1 product.

Genomic rearrangements have in recent years gained attention due to their evolutionary role in processes related to adaptation to local environmental conditions as well as diversification and speciation. In this study, we report on genomic rearrangements in the cold-water adapted polar cod ( Boreogadus saida ), a keystone Arctic fish species. By taking advantage of a new chromosome-level genome assembly in combination with whole-genome population sequencing data from specimens across the northern Barents Sea and adjacent regions, we identified a substantial number of larger chromosomal inversions (n=20) and characterized the previously identified chromosomal fusions (n=5). These genomic features — encompassing over 20% of the genome — exhibited genetic divergence, strong internal linkage disequilibrium, and signals of selection. Two of the identified inversions were associated with the two previously described hemoglobin clusters, while a third chromosomal region was found to differentiate between males and females. Moreover, clustering analyses on genotype frequencies of inversions revealed sub- structuring according to five geographic sub-groups suggesting sub-populations and/or the existence of cryptic ecotypes. These results provide novel insights into the impact of genomic rearrangements in population divergence and thus, potentially local adaptation, especially in species with high gene flow.

The results of oceanographic research in the marginal ice zone of the Barents Sea near the ice cover boundary, carried out from the R/V Dalnie Zelentsy from April 27 to May 6, 2023, are presented. The position of the frontal zones recorded from contact observations on hydrological meridional transects along 33°30′, 40°, 45°, and 50° E are considered. The transects were made from the fields of finely broken annual ice southward towards the open water area of the Barents Sea. High-gradient zones expressed in the temperature and salinity fields at different distances from the ice field edge were detected on all transects. It was shown that during the research period the frontal zone was located at a distance from 25 to 180 km from the ice field edge, the temperature gradients varied from 0.021 to 0.067 °C/km, the salinity — from 0.002 to 0.012 psu/km, the width of the frontal zone did not exceed 28 km. The maximum values of chlorophyll-a and dissolved oxygen were observed in the area of the frontal zone boundary.

This paper analyses the anomalous hydrometeorological situation that occurred at the beginning of 2012 in the seas of the Russian Arctic and Russian South. Atmospheric blocking in the temperate zone and the extension of the Siberian High to the Iberian Peninsula (known as the Voeikov et al. axis) led to a positive anomaly of air and water temperatures and a decrease in the ice extent in the Barents and Kara Seas. At the same time a prolonged negative air temperature anomaly was recorded in central and southern Europe and led to anomalously severe ice conditions in the Sea of Azov. Winter hydrographic conditions in the Barents and Kara Seas are illustrated by a unique set of observations made using expendable bathythermosalinographs (XCTD)

The distribution of bacterio- and zooplankton was studied in West Spitsbergen (Svalbard) coastal waters in August 2009. The bacterial abundance and biomass varied from 110 to 3360 × 103cells/ml and...

Based on the results of multiannual oceanographic research at the Murmansk Marine Biological Institute in the “Kola Meridian” secular section, the recent tendencies of cyclic climate changes in the...