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Quantitative characteristics of macrozoobenthos in the rivers of the Kandalaksha coast of the White Sea as a forage base for juvenile salmonids. - Baryshev I. A. and Khrennikov V. V. - The macrozoobenthos structure in the rivers of the Kandalaksha coast of the White Sea and the forage base of juvenile salmonids are analyzed. 84 species (92 taxonomic groups) have been found, among which aquatic insect (Ephemeroptera, Trichoptera, and Diptera) larvae predominate. Scarce benthic communities in the mountain rivers (1.6 thousand ind./m2 and 2.4 g/m2) and relatively rich ones in the lowlands (10.3 thousand ind./m2 and 7.4 g/m2) were noted. The forage base development level was evaluated as medium and, in some places, high; its increase from the river sources in the mountains to the mouths was traced.
Areas with much higher benthos abundance and rich forage base are shown to form in the lake outlets. Favorable conditions for the feeding and growth of juvenile salmonids were found in the rivers.
Key words: salmonids, bottom communities, Kola Peninsula.
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Seasonal changes in the hormonal response of Eversmann hamster (Allocricetulus eversmanni, Cricetinae, Rodentia) males to conspecific females' olfactory signals. - Kropotkina M. V., Kuznetsova E. V., and Feoktistova N. Yu. - Reproductive success demands both the male and female getting a particular physiological status, which is usually provided in rodents by certain olfactory signals. The hormonal response of Eversmann hamster (Allocricetulus eversmanni) males to the natural excretes (urine, midventral gland secretion (MVGS)) of conspecific females was studied during several seasons of the year, the animals kept in the conditions of natural lighting and temperature regimes. In the autumn, no reliable changes of the testosterone level in males in response to any presented signal were noted. In the winter and spring, a reliable
(P < 0.05) increase in the testosterone level was caused by the female MVGS odor. In the summer, a similar reaction to conspecific female urine (P < 0.05) was noted only. Moreover, in the summer and autumn, males showed a reliable decrease of the cortisol level in response to the female urine odor (P < 0.05). In the winter and spring, a similar result was caused by exposition to both odors. The progesterone level in males reliably (P < 0.05) increased at exposure to both female urine and MVGS in all the seasons of the year, except for the female MVGS in the summer. Therefore, the decreased cortisol level in combination with the simultaneously increased testosterone and progesterone ones allow the males of the species under study to achieve their maximum reproductive success, despite the high degree of their intraspecific aggression.
Key words: Allocricetulus eversmanni, urine, midventral gland secretion, testosterone, progesterone, cortisol.
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Northern Urals bird classification by similarity of their distribution and residence time. - Livanov S. G. - Year-round route surveys of birds on a flat section of the Pechora-Ilytch biosphere reserve were conducted in 1995 - 1997. In total, 7 habitats were surveyed for the two years, 1,500 km of counts were travelled, and 136 bird species were met. Using multidimensional factor analysis, it has been established that in the Northern Ural region, during their stay in the course of a year, 50 (37%), 70 (51%) and 16 species (12%) prefer wood, villages, and semi-open and open wetland habitats, respectively. 49 species (36%) gravitate to any available habitats in the region during their migrations, and there is no group preferring the winter period.
Key words: birds, year-round counts, distribution, multidimensional analysis, classification, preference, habitat.
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Fertility evaluation of ecologically different forms of house mice and their hybrids of the superspecies complex Mus musculus sensu lato (Rodentia: Muridae). - Maltsev A. N., Ambaryan A. V., and Kotenkova E. V. - In house mice from the superspecies complex Mus musculus s.l., the relative weight of their testicles is higher and the sperm quality is better for the exoanthropic species than for the synantropic ones. It is shown that this pattern is observed at an intraspecific level as well, since the testicle weight index and sperm concentration were significantly higher in the hemi-synantropic subspecies Mus musculus wagneri and M. m. gansuensis as compared to the synantropic M. m. musculus in a few comparisons. The heritability of these indices should be considered when interpreting the results of experimental crosses in house mice.
Key words: Mus musculus wagneri, Mus musculus gansuensis, Mus musculus musculus, house mice, sperm quality, relative mass of testes, fertility.
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Arthropod abundance on bustard nesting sites in the Saratov Trans-Volga region. - Oparina O. S. and Oparin M. L. - The results of our study of the quantitative and qualitative arthropod composition at potential nesting areas of Otis tarda in the Saratov Trans-Volga region are presented. Specific information obtained at 7 areas (2 fallow fields, two fields of winter and spring wheat, two natural fallow lands of different ages, and virgin land) in 2012 is given. A comparative analysis of some indicators of the arthropod abundance and biomass on winter fields treated with chemicals and untreated is conducted. The obtained results are compared with those of previous years. In the Saratov Trans-Volga region in the nesting period O. tarda currently has favorable conditions for rearing nestlings on natural fallow lands of different ages and on early-spring crop fields.
In winter fields after their complex treatments with chemicals the abundance and composition of arthropods cannot meet the needs of O. tarda during rearing nestlings.
Key words: Otis tarda, habitat, food supply, arthropods, abundance, biomass, Trans-Volga region.
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Seasonal aspectivity of the bird population in the Yelabuga City. - Soloviova E. A. - On the basis of our year-round bird counts in the Yelabuga City located in the northeastern part of the Republic of Tatarstan from 16.10.2010 till 15.10.2012, a seasonal periodization of the population was revealed. The validity of our surveys and variations of the boundaries of the periods and their amount were analyzed. 9 common seasonal aspects of the bird population were found for all habitats in the city. Their description averaged over the city is given. Features of the intra-annual ornithocomplex dynamics were revealed. Inter-annual changes were followed in the formation of the spring, autumn and winter appearance of the community. The Eurasian tree sparrow predominated during the annual cycle averaged over the city.
The great tit predominated during flying away and flight of birds, autumn, as well as during the pre-winter and winter migrations. The common chaffinch predominated during the period of mass bird arrival. The rock dove predominated during the start and end of the migration.
Key words: bird population, seasonal aspect, temporal dynamics.
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Changes in the abundance and feeding range of rotifers from the genus Asplanchna (Eurotatoria, Rotifera) in a pond (the Sura river basin). - Stojko T. G., Senkevich (Burdova) V. A., and Mazei Y. A. - The paper presents data on the abundance, occurrence frequency, feeding range and reproduction of three rotifer species from the Asplanchna genus (A. henrietta, A. priodonta, and A. sieboldi) in a pond of the Urleyka river in the summer of 2014. In early June, the abundance of these species was approximately identical. In July, the abundance of A. priodonta and A. sieboldi became smaller and they disappeared in August, whilst the abundance of A. henrietta increased. The rotifers from the Asplanchna genus are omnivorous. The ration of A. sieboldi and A. priodonta is identical, but the proportion of animal food is much higher in the first species.
The decrease in the food amount was the cause of falling their abundance in July and the full disappearance in August. The A. henrietta species filled the corresponding vacant niche and bred successfully in July and August by using vegetational food and a wide range of animal one.
Key words: Asplanchna, abundance, range of feeding, reproduction.
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Can major roads be absolute barriers to small mammals' movement? - Tolkachev O. V. - The influence of a major road on small mammals' movement was investigated. Muroid rodents were used as the model objects. Two years of our observations using the technique of extensive tetracycline bait marking have shown that the road could be an absolute obstacle to small mammal movements. The extreme barrier effect was determined by some construction features of the road, namely, the presence of a physically impassable median strip along it with the absence of any conduits for rodent movements connecting the road's sides. The migration disconnectedness among animals on the opposite sides of the road has resulted in the formation of demographically distinct units, which are equivalent to separate populations.
Key words: rodents, roads, barrier effect, landscape fragmentation, population subdivision, isolation.
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Ecologo-biological characteristic of natural steppe biogeocenoses in the Central Caucasus (the Terskiy variant of vertical zonation, Kabardino-Balkaria). - Uligova T. S., Gorobtsova O. N., Tsepkova N. L., Rapoport I. B., Gedgafova F. V., and Tembotov R. K. - An ecologo-biological characteristic of the natural steppe biogeocenosis components in Kabardino-Balkaria (within the Terskiy variant of vertical zonation) is given. The research results of biological features of common chernozem calcareous soils (humus contents, enzymatic activity, and soil respiration intensity), their spatial and profile distribution combined with basic ecological factors are represented. A list of abundant plant species and their ecological characteristics are given; the specific composition and abundance of mesofauna representatives (earthworms) in the area of common chernozem soils were studied.
Key words: Central Caucasus, common chernozem calcareous soils, steppe zone, humus, enzymatic activity, soil respiration, phytocenoses, earthworms.
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Changes in the structure of the rhizosphere complexes of actinomycetes of transgenic tomato (Solanum lycopersicum L., Solanaceae, Solanales) with the gene Fe-SOD 1. - Shirokikh I. G., Nazarova Ya. I., Ogorodnikova S. Yu., and Baranova E. N. - Tomato transformants (Solanum lycopersicum L.) with the gene of Fe-superoxide dismutase (Fe-SOD 1) from Arabidopsis thaliana L. making the plant resistant to the damaging effect of oxidative stress were used in our work. The original-genotype tomato and independent transgenic lines bn 6 and bn 4 were grown in artificial climate. According to the results of determination of the total SOD activity and lipid peroxidation, line 6 bn differs from both the original genotype and line 4 bn by more balanced lipid homeostasis.
Under the influence of gene insertions, realignment occurred in the rhizosphere of the line 6 bn plants, in the structure of their actinomycetes complexes. They were expressed as changes in the occurrence frequency and relative abundance of representatives of individual genera, sections and series in the complex, as well as antagonist species, cellulolytic and auxin producers.
Key words: tomato, transformant plant, Fe-containing superoxide dismutase (Fe-SOD 1), rhizosphere, actinomycetes, structure of complex, taxonomic composition, functional activity.
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Assessment of indices of tundra phytocoenosis pollution with polycyclic aromatic hydrocarbons. - Yakovleva E. V. and Beznosikov V. A. - 14 structures of polycyclic aromatic hydrocarbons (PAHs) were identified in the organogenic soil horizon and plants of the south shrub tundra belt, at a background plot and at a coal mine. The polyarenes in soils and plants were mainly represented by light structures. On the background and polluted areas, mosses of Pleurozium schreberi, Polytrichum commune and grasses of Deschampsia caespitosa, Festuca ovina contained the highest PAH amounts. PAH bioaccumulation in plants is mainly dependent on their physiological features. 4 plant groups with different PAH bioaccumulation capabilities were identified on the basis of the calculated biological absorption coefficient.
The toxicological activity of polyarenes for both soils and plants at the background and polluted areas was determined by heavy PAHs. The highest values of toxicological activity were observed for mosses and grassy plants whilst the lowest values were for shrubs. PAHs at the plots under study are mainly of petrogenic origin.
Key words: pollution indices, polycyclic aromatic hydrocarbons, soils, plants.
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