Vol 144, No 1 (2024)

The genetic potential of ungulates of the Arctic zone of the Russian Federation is rich and diverse, but requires modern research. The use of genetic systems makes it possible to study the genome of animals, determine the state of the genetic diversity of the species, suggest reasonable ways to maintain the level of heterozygosity in domesticated animals, purposefully obtain individuals that are necessary for humans. The analysis of the above-described gene pools of their structure is interesting both for modern breeding and environmental genetics, and may be in demand in the future when planning the development of animal husbandry in the Arctic zone for decades to come. The unique adaptive capabilities of animals to the harsh conditions of the Far North open up wide opportunities for their rational use. Reindeer, musk ox and snow sheep are the most important components of high-latitude ecosystems, in which other ungulate species can practically not live, so they are of great scientific and practical value in preserving agro-diversity in the Arctic zone of the Russian Federation.

An analytical review of scientific publications containing materials or discussion of the concept of sexually selective infanticide (SSI) in brown bear populations (Ursus arctos) is presented. The authors of the SSI concept refer to the idea of sexual selection, which is a rather shaky conceptual basis. The concept was formed largely on the basis of materials obtained during the study of intraspecific relations in lion populations (Panthera leo). However, the facts from the behavioral ecology of the lion, which accumulate relatively quickly, can be interpreted quite ambiguously and even only when applied to this species, the concept of this does not look convincing enough and is obviously unnecessarily anthropomorphic. Infanticide, cannibalism and their combination are recorded in both lion and brown bear populations. However, the behavioral ecology of these species differs significantly. Brown bear populations are characterized by: pronounced seasonality of reproduction; the presence of a reproductive interval in bear females, which can vary significantly in populations with different habitat conditions and varies from 1 to 5 years; mating patterns can vary from lax monogamy to panmixia. Multiple paternity is possible within the litter (single fertility) of a brown bear. It follows from the review that brown bear populations are characterized by many features of sociality, the lifestyle of bears being both solitary and group. It is hardly correct to classify the brown bear (and other species of bears) as uniquely unsocial. From the analysis of publications on the behavioral ecology of the brown bear, it follows that the application of the SSI concept without significant additions is hardly useful for understanding the intraspecific relations of this species.

This review summarizes information on the main negative factors affecting the state of floodplain water bodies ecosystems, describes the most common consequences for abiotic and biotic processes, and suggests possible ways to conserve these ecosystems. Evidence of the negative impact of hydraulic construction, embanking of floodplains, channelizing of rivers, agriculture, and other anthropogenic impacts is presented. A special role is played by climate change, which leads to a decrease in flood inundation, drying and overgrowing of water bodies, and their eutrophication. The authors suggest criteria to choose correct indicators that can testify not only to special stages of water body succession (e.g., vegetation) or its trophic status (zooplankton), but also to the long-term effects of anthropogenic and climatic changes. As a recommendation, it is proposed not to consider water bodies separately, but to assess the whole waterscapes and use the change in β-diversity as an indicator. Further conservation strategies can be based on the approaches of the Red List of Ecosystems of the International Union for Conservation of Nature and Natural Resources (IUCN), which will help to draw attention to the problem. The key role for the conservation of floodplain water bodies should be played by territorial protection measures, up to the development of a separate category for small water bodies.

Experimental results of daily counting under a microscope for 30 days of prokaryotic cells in preparations from soil samples when stained with different specific dyes and literary results on daily counting of bacteria in soil using different methods are presented. The FITC dye, which stains the entire set of bacterial cells, revealed a wave-like dynamics of cell numbers with different numbers of oscillations in the form of peaks in all experiments. Using the SFDA dye, which detects only living, metabolically active cells, wave-like dynamics were also revealed, but their oscillating number was significantly less. The reliability of oscillations and differences in cell numbers when using different dyes were confirmed statistically and by harmonic analysis. The wave-like dynamics of living, metabolically active cells is a consequence of the cycles of growth and death of bacterial cells and short-term trophic succession in the microbial community. External disturbing influences did not affect the manifestation of wave-like population dynamics, both in the population of living cells and in the total number of cells. The phenomenon of wave-like dynamics of non-living bacterial cells and their numerical superiority is explained by the fact that cells, losing viability, lyse and disintegrate not immediately after dying, but with some delay in time. This leads to the accumulation and permanent superiority of the pool of dead cells when microscopically counting the total number of bacteria in the soil and explains the discrepancy in bacterial numbers between different counting methods. The presented experimental and literary material will serve as a substantiation for microbiologists and biotechnologists of the need to control the dynamics of the numbers of introduced populations and communities of microorganisms into the natural environment, as well as a source of knowledge for the successful management of natural microbial communities.