Том 45, № 10 (2018)

Molecular genetic typing of voles from the vicinity of the Pslukh cordon (south of the Caucasian state reserve), Krasnaya Polyana, and from the Utrish reserve (the Abrau peninsula) has been carried out. Based on the nucleotide sequence of the mitochondrial cytochrome b gene, voles from Krasnaya Polyana and the Psulkh cordon should be attributed to Asia Minor voles (Chionomys roberti), and the animals from Utrish, to the Eastern European voles (Microtus rossiaemeridionalis). The Asia Minor voles belong to the North Caucasian phylogenetic branch of the species. The analysis of body measurements of voles from Krasnaya Polyana and Lazarevskii region (without molecular examination) showed that these animals also most likely belong to the Asia Minor voles (not to Gudaurskii, as was mistakenly considered earlier). Some information on the ecology of the Asia Minor voles in the region is given.

The population of the continental oystercatcher subspecies in the conditions of the middle reaches of the Medveditsa River in the nesting period of 1996–2008 was stable, namely, three pairs, out of which two, rarely three, nested annually. The clutch size was 2–3 eggs. Our many-year survey has established a tendency toward a significant decrease in the reproductive success against the background of transformations of nesting and feeding habitats, which is determined by the long-term tendency toward a reduction in the water level in the river.

The abundances of virioplankton and planktonic picocyanobacteria in deep and shallow water sites of Rybinsk Reservoir during the freezing period (water temperature 0.3–0.9°C) varied from (37.1 to 84.1) × 10⁶ ((57.3 ± 2.1) × 10⁶, on average) particles/ml and from 13.5 to 75.0 × 10³ ((48.7 ± 3.4) × 10³, on average) cells/ml, respectively. The fraction of picocyanobacteria with viruses attached to their cell surface was 6.5–29.0% (12.0 ± 0.8%, on average). The proportion of visible infected cells was 0.7–7.6% (2.2 ± 0.3%, on average) of the numbers of picocyanobacteria. It is likely that viruses play an important role in the regulation of picocyanobacteria abundance during the freezing period.

The microorganisms Bacillus circulans NSh, B. firmus OBR 1.1, B. firmus OBR 3.1, Solibacillus silvestris OBR 3.2, B. circulans OBR 3.3, Halomonas sp. OBR 1, and Erwinia rhapontici OBR 4.1, isolated from drill cuttings, were shown to be able to degrade oil, mineral oil, and diesel fuel. The B. circulans NSh and B. firmus OBR 1.1 bacteria were shown to degrade 62 and 32% of oil, respectively, in an alkaline medium (pH 9) after 14 days and 42 and 22% of oil, respectively, in a saline medium (10% NaCl). Under conditions of increased ambient salinity and alkalinity, the B. circulans NSh and S. silvestris OBR 3.2 bacteria were shown efficiently to degrade petroleum hydrocarbons not only individually, but also in combination with the oil-oxidizing Dietzia maris AM3 microorganism. The efficiency of oil degradation by the consortium composed of B. circulans NSh D. maris AM3 was higher than that by monocultures.

Regression analysis of the size and weight structure of dreissenids (D. bugensis and D. polymorpha) from the Volgograd Reservoir has been carried out. The power-dependence parameters in the resulting equation are different for the two studied mollusk species (W = 0.036L^3.33 for D. bugensis and W = 0.064L^3.32) for D. polymorpha. The established regression relationship between the individual body weight (W) and the shell length of the mollusk (L) has a high degree of correlation R² = 0.96 at a significance level of p = 0.01. The results can be used for reconstructing the individual weight of mollusks from the shell length during trophological studies in Lower Volga reservoirs.

This paper summarizes the results of our long-term research (2007–2015) of chironomids in 38 saline and hypersaline lakes of Crimea. Chironomid larvae were found at salinities up to 340 g/L, and the frequency of their occurrence decreased as salinity rose above 30–50 g/L. We identified four species, namely, Baeotendipes noctivagus, Cricotopus gr. cylindraceus, Tanytarsus gr. Mendax, and Paratanytarsus gr. quantuplex. The numbers of chironomid larvae varied within wide limits and peaked at the levels of up to 8000/m³ in plankton, up to 9000/m² in the benthos, and up to 3000/m² on the floating mats of filamentous green algae. The abundance, biomass, and production of larvae were nonlinearly dependent on the salinity. A salinity increase led to a decreased number of species and reduced average sizes. The maximum values were observed within 150–170 g/L.

Morphoanatomical features important for plant adaptation to ecological conditions have been described for seeds of seven Iris species growing in the Saratov region. Such features are the most indicative for seeds of two species, I. halophila Pall. and I. pseudacorus L. The strategy of I. halophila seeds represents development of adaptations intended to protect seed contents against penetration of saline solutions. These adaptations include the presence of a waterproof and salt-proof coating film protecting seed contents against saline solutions, the maximum level of a seed cover lignification as compared with the seeds of other species studied, and a smooth ultrasculpture of a seed cover preventing salt deposition on its surface. The strategy of I. pseudacorus seeds includes formation of seeds capable of surviving in an aquatic environment for a long time without any loss of viability. The corresponding adaptations are the following: a flattened discoid form of seeds facilitating their floating in water; the maximum thickness of a seed cover compared to other species studied; weak lignification of the seed cover, especially mesotesta; and the presence of an air cavity in the chalazal part of a seed, which reduces its specific gravity and presumably provides an embryo with oxygen when seeds float in water. Seeds of five other iris species (I. aphylla L., I. pineticola Klokov, I. pumila L., I. sibirica L., and I. tenuifolia Pall.) have identical adaptations to moderate conditions of a terrestrial environment.

Our hypothesis that exoanthropic forest rodent species (e.g., bank voles) avoid the urinary odor of the synanthropic house mice was tested in field experiments in August 2016. One count of the small mammals was carried out in each of two 4-ha fields by the capture–mark–recapture technique over 12 days. Two hundred live traps (100 points, 2 traps per point) were exposed and controlled twice a day (early in the morning and in the evening) in each count. One trap in each pair served as the reference, while the second was the experimental one with 20 μL of the urine of synanthropic house mice applied to a foam rubber surface every day. Generally, bank voles chose the odorless trap more often (60.8% vs. 39.2%, χ² = 3.7, p = 0.054). Adult individuals had a nonsignificant tendency to avoid the odor-emitting traps. Immature (subadult and juvenile) bank voles reliably avoided the odor-emitting traps (a 2 : 1 ratio, χ² = 5.74, p = 0.017). A general linear model showed the influence of the age of voles on the choice of the odorless traps. The potential repellent role of sulfur-containing compounds in mouse urine is discussed.

Comparative assessment of the importance of nature conservation in different shoreline areas has become a relevant task as the strategy of sparing management of natural resources is developed for areas impacted by existing and planned water reservoirs. Integral biodiversity indices that characterize species diversity along with abundance parameters for every animal species sighted were developed for the area that would be influenced by the Lower Zeya Hydropower System (currently at the planning stage). The present article includes lists of mammals, reptiles, and amphibians seen in the area, grading scales for the abundance of species and ecological groups of terrestrial vertebrates, a list of the main biotopes, zoning principles for the areas influenced by the reservoir, formulas for calculating the integral parameters of species diversity and animal abundance, and schematic maps of the spatial distribution of the values of integral indices of richness and nature protection significance of the animal populations. Specific recommendations for strengthening the network of Special Protected Natural Areas are given. This study allows for the conclusion that construction of the Lower Zeya hydropower plant will be associated with a high risk of negative consequences for biodiversity and ecological stability on both the local and regional levels.