The Impact of Sea Ice Loss on Benthic Communities of the Makarov Strait (Northeastern Barents Sea).

The continental shelf of the northeastern Barents Sea is presently experiencing a weak influx of Atlantic water from the west. In recent times, warming in Arctic regions has led to an increase in extended ice-free periods in this area, instead of significantly elevating water temperatures. The implications of this phenomenon on the structure and functioning of benthic communities were investigated during the autumn of 2019 within the Makarov Strait, located in the southwestern part of the St.

First Evidence of Microplastic Occurrence in the Marine and Freshwater Environments in a Remote Polar Region of the Kola Peninsula and a Correlation with Human Presence.

Microplastics (MPs) have even been detected in remote environments, including high-latitude regions, where human activities are restricted or strongly limited. We investigated the surface water of the bays of the Barents Sea and the freshwater lakes that are located close to and several kilometers from a year-round resident field station in the remote tundra region of the Kola Peninsula. The microplastics' presence in aquatic environments in this region has not been indicated yet.

Collembola (Hexapoda) as Biological Drivers between Land and Sea.

Macroalgae debris accumulated onshore function as points of interaction between marine and terrestrial ecological systems, but knowledge of the importance of detritivores facilitating the introduction of organic matter via the detritus pathway into neighbouring ecosystems, is still poorly understood. In particular, not much is known about biodiversity patterns and the colonisation of macroalgal debris by terrestrial, detritivorous soil microarthropods in the harsh environmental conditions in the subpolar Arctic region. We hypothesised that (i) soil microarthropods of the coastal tundra, including Collembola, can cross the ecosystem boundary and colonise decaying and freshly exposed macroalgae; and (ii) various inundation regimes by sea water, microhabitat stability and decaying of macroalgae drive distribution patterns of collembolan species.

Phylogenetic Relatedness within the Internally Brooding Sea Anemones from the Arctic-Boreal Region.

Phylogenetic analyses based on mitochondrial 16S rDNA, nuclear 28S rDNA, and morphological and ecological traits of and sea anemones inhabiting the Arctic-boreal region indicate discordances between trees derived from molecular sequences and those based on morphological traits. Nuclear genes were more informative than mitochondrial and morphological datasets. Our findings indicate that 16S rDNA has limited applicability for phylogenetic analyses at lower taxonomic levels and can only be used for distinction of families.

[THE HEART ELECTRIC FIELD ON THE THORAX SURFACE OF SPORTSMEN-SWIMMERS DURING VENTRICULAR REPOLARIZATION UNDER ACUTE NORMOBARIC HYPOXIA].

The study of the electrical activity of the sportsmen-swimmers' heart has been carried out during ventricular repolarization under short-term acute moderate normobaric hypoxia. It was revealed that acute hypoxia leads to a significant decrease of the duration of the early ventricular repolarization immediately after hypoxic exposure, of the duration of the late repolarization - at last minutes. The structural change of ventricular repolarization of the heart of the athletes surveyed was shown based on the changes in amplitude-temporal characteristics of the extrema of the heart electric field during the ventricular repolarization of the heart upon acute hypoxic exposure.