Priority data are presented on the chromosomal (routine, C-banding) and molecular (cyt b, p53) marking of several (n = 19) individuals of common vole sibling species from three previously not studied localities in the Central Black Earth region, at the territory of the Deer Natural Park (Lipetsk Region, Krasninsky District). All individuals caught on the territory of the Deer Natural Park in the northwestern part of the Lipetsk Region were identified by both genetic markers as M. arvalis form “arvalis” (MAA). No representatives of other M. arvalis s. l. sibling species, including recombinants, were found in our samples. The geographical location of the M. arvalis form “arvalis” found by us was estimated with respect to the distribution boundaries and hybridization sites of the 46-chromosome forms of M. arvalis s. l. in the Central Black Earth region. It is shown that the studied individuals have been caught within the range of the Microtus form “arvalis” and are largely removed from the hybridization sites of the 46-chromosomal forms M. arvalis s. l., discovered earlier in the southern Lipetsk region and the southeastern Kursk Region. No M. rossiaemeridionalis in the examined sample from the Deer Natural Park were found. The correspondence between the samples studied and identified as the M. arvalis form “arvalis” from the Deer Natural Park and native meadow biotopes is shown. The data of determining the taxonomic status of M. arvalis s. l. individuals from the Deer Natural Park are consistent with our perceptions of the nature of the geographical distribution and biotopic correspondence of M. arvalis s. l. sibling species and the chromosomal forms on the territory of the Central Black Earth region.

The morphological variability of the aerial vegetative and generative organs of Melilotus officinalis in the ecotone communities of the forest-steppe zone, the forest zone of the Republic of Tatarstan including desecrated parts of the forest zone was studied. The ascorbic acid content in various parts of the plants growing in these habitats was also analyzed. It was revealed that the realization of the morpho-physiological potential of plants was determined by the conditions of botanical-geographical zones. The sweet clover, growing on black soils under the conditions of ecotone communities of the forest-steppe zone, was found to have higher indicators of “total biomass”, “biomass of leaves”, “biomass of inflorescences”, etc., as compared to the plants from similar communities growing on gray soils of the forest zone. Under the conditions of the ecotone communities of the forest-steppe zone, the content of ascorbic acid in all parts of the plant was also higher. Melilotus officinalis, growing in the conditions of a desecrated soil layer, was characterized by the maximum realization of its biomorphological potential with a low value of the coefficient of variation (CV), which reflected a stronger homogeneity of the samples. In the plants growing under extreme conditions, a sharp increase in the concentration of ascorbic acid in all parts was observed, which could be considered as an important mechanism for the adaptation of the species to survival under conditions of a sharp temperature difference of the substrate. Along with an increase in the generative period, an important component of the species adaptation was the low correlation between the indicator “biomass of inflorescences” and the concentration of ascorbic acid in inflorescences, “biomass of inflorescences” and the concentration of ascorbic acid in the leaves, which reflected the stable process of formation of the generative system of sweet clover. All coenopopulations were characterized by an incomplete ontogenetic spectrum with an absolute maximum on the plants with the middle-age ontogenetic status (95%).

Heavy metals are most common soil pollutants, including agricultural land. At the same time, the level of heavy metal pollution can significantly exceed the standards. Pea (Pisum sativum L.) and wheat (Triticum aestivum L.) are most important crops. At the same time, no comparative analysis of their resistance to high concentrations of heavy metals has been carried out. In connection with this, the resistance of T. aestivum and P. sativum seedlings to the chronic effects of lead and copper salts in the range of lethal concentrations for T. aestivum was comparatively evaluated (0.15, 0.30 and 0.60 g/L of copper sulfate; 0.5, 1.0 and 1.5 g/L of lead nitrate) in experimental conditions. All studied concentrations of the toxicants caused a decrease in seed germination of T. aestivum relative to the control by 19–38% and 23–58% when exposed to lead nitrate and copper sulphate, respectively, which indicated the manifestation of lethal effects. All studied concentrations of both toxicants caused a significant reduction in the root system length (from 69% to 25 times) and shoot height (by 25–76%) as compared with the control level in T. aestuvum seedlings, and also led to an increase in the intensity of lipid peroxidation in seedling shoots, indicating the development of a stress reaction. At the same time, the studied concentrations of heavy metal salts, which were lethal for T. aestivum, did not cause almost any disturbances of the studied parameters in P. sativum, except for a decrease in the root system length after lead nitrate exposure. Thus, seed germination, growth processes of the root system and shoot, as well as peroxide homeostasis in P. sativum seedlings were much more resistant to the studied concentrations of lead nitrate and copper sulfate as compared with these parameters of T. aestivum.

Currently, septoria is the basis of the pathogenic complex on wheat crops in Russia, occupying the predominant position among harmful fungal diseases. In case of severe wheat damage, the crop loss caused by the fungus Z. tritici, makes up from 10–25 to 40–60%. The crop loss caused by the fungus P. nodorum parasitizing is from 10–20 to 30–50% during the years of epiphytoty. The question of the economic significance of P. avenae has not yet been examined completely. However, depending on the area of wheat cultivation and the year of observation, its part in the septorian population may reach up to 76.9%. It was of interest to study in detail the influence of conditions of the specific year, life form, and species of wheat on the formation of the species composition of Septoria in the pathogenic complex of wheat. Among the complex set of factors included in the concept of the environment, a significant role belongs to its abiotic components, namely, climate and weather, but the variety as an environment-forming factor has a decisive role. Our studies were carried out during 2010–2017. During the research period, the weather conditions varied significantly over the years and were not always favorable for the development of plants and formation of a good wheat crop. During the study, deviations in the amount of precipitations during the vegetation period, and, in general, over the year from the long-term average annual values, were noted. The years of 2012, 2014 and 2015 were characterized by the highest moisture supply during the vegetation season. It has been predicted that cooler days of April and May will promote the better development of P. avenae and P. nodorum. P. nodorum receives its predominant development during the years with wetter weather within the vegetation period of wheat, in contrast to Z. tritici more resistant to low humidity. These data demonstrate adaptation of the pathogen to conditions of an increased temperature regime and reduced rainfall amount.

The Orchids due to their biological features, high decorative properties and poor resistance against anthropogenic factors are one of the most vulnerable components in vegetation of the world. Their conservation cannot be efficient without the knowledge on their reproductive biology. These data are especially important for species on the borders of their distribution area with additional reproduction limiting factors. Our study object is a rare orchid species Epipactis atrorubens (Hoffm.) Besser. During field works on the territory of the Komi Republic (northeast Russia), we studied 50 populations of E. atrorubens. Reproductive characteristics (fruit set, seed productivity and seed morphometry) were studied in 19 of them. We established that the main limiting factor in the North is a short vegetation period. Frosts damage generative shoots and do not allow seeds to ripe. The capsule of E. atrorubens on the northern distribution border contains fewer seeds than in the central part of areal. Also less is the indicator of real seed productivity. Within the Komi Republic on sample of two sites (the Timan Range and the Ural Mountains), we also see the decrease in all reproductive characteristics from south to north: the number and size of flowers, the number and quality of seeds decrease, their shape changes. However deterioration in seed productivity is compensated by an increase in seed volume. The populations of less than 50 shoots, in which juvenile plants are not marked, are in critical condition.

According to the data collected in the second half of summer for the period from 1954 to 2016 in the flat and mountainous parts of Western Siberia, the distribution and number of the narrow-headed vole in the zonal and provincial aspects were analyzed. Based on the cluster analysis of the matrix of similarity coefficients of abundance indicators obtained by averaging the initial data by years and groups of geobotanical maps units, the classification of habitats according to the favorable environmental conditions degree for the vole is made. The averaged samples are divided into five types of favorability: from optimal, where the abundance of the species is highest in the whole studied area, to extreme, where it is not encountered. In the South of the West Siberian plain narrow-headed vole prefers steppes, and in the subarctic tundras – communities of river valleys. In the Altai and Kuznetsk-Salair mountain regions it is most common in the subalpine light forests, tundras and tundra-steppe of the North-Western and SouthEastern Altai. On average, this vole prefers open habitats in Western Siberia. According to the classification and the structural graph, the dependence of the vole abundance on a number of factors and their inseparable combinations (enviromental and anthropogenic regimes) was revealed. The greatest connection with its distribution in the habitats of Western Siberia is traced for heat and water availability. On the plain, the number of this vole increases from the middle taiga, where it is found only once, to the subzone of the subarctic tundras in the North and to the forest-steppe and steppe zones in the South. In the mountains its more in the South-Eastern Altai, where a relatively high proportion of the most favorable for narrow-headed vole habitats.

Features of the species and spatial structure of macrobenthic sublittoral communities in a lagoon ecosystem on the Green Cape (the White Sea) were studied. 31 invertebrate species and 3 species of sea grasses and algae (Zostera marina, Cladophora sericea, and Fucus vesiculosus) were found in the sublittoral of the surveyed lagoon. The data on the species composition, diversity and spatial structure of macrobenthos communities indicate the predominance of littoral brackish-water and marine euryhaline macrobenthos species (Hydrobia ulvae, Tubificoides benedii, Chironomus salinarius, and Macoma balthica) in the coastal region of the lagoon, marine euryhaline littoral and sublittoral species (mainly polychaetes Heteromastus filiformis, Polydora ciliata, and Capitella capitata) in the central deeper region, and marine sublittoral less euryhaline species (Pontoporeia femorata, Anonyx nugans, Nereimyra punctata, Terebellides stroemi, Astarte montagui, Micronephthys minuta, and Atylus carinatus) at the exit from the lagoon. The ecosystem of the Green Cape lagoon belongs to lagoons significantly fenced off from the sea with depleted specific fauna (many littoral species) and largely influenced by carbon load and salinity. The reduced connection of the lagoon with the sea due to the continued rise of the White Sea coast (4 mm per year in this area) will contribute to a decrease in the species diversity and the predominance of few small eurytopic invertebrate species resistant to organic load, oxygen deficiency, and desalination.

The article presents a bioclimatic model of the potential range of Bulbocodium versicolor in European Russia. To build the model, we analyzed a matrix containing 166 B. versicolor localities in the studied region; the analysis was carried out in the SDMtoolbox program using the climatic paramaters from the WorldClim open database. The model demonstrates that, given the available dataset on the modern climatic conditions, B. versicolor may occur in a wider geographical range comprising, at the very least, the Belgorod, Voronezh, Volgograd, Lipetsk, Penza, Rostov and Saratov provinces. Also, within European Russia, the most favorable conditions for B. versicolor are found in most of the Voronezh and Volgograd provinces as well as in some areas of the Right Bank and Left Bank of the Volga River adjacent to the Volga Upland (in the Saratov province). The maximum occurrence probability is 70–100% while the average occurrence probability is 40– 60%. The maximum contribution to the model is made by the precipitation of the warmest and most humid quarter (June–August); a smaller contribution is made by the average temperature of the coldest (December–February) and warmest (June – August) quarters as well as by the average annual precipitation. The least contribution is made by the precipitation of the most humid month (July) and the driest quarter (March–May). Finally, we conclude that bioclimatic model facilitates a better understanding of the geographical distribution of the species in question.

In the birch-pine forests of the Ilmeny Reserve the bank vole is predominated by numbers, the pygmy wood mice being in the second place. The results of our monitoring of the numbers of these rodents for 27 years (1991–2018) are presented. 1,610 rodents were caught,of which the bank vole accounted for 52.6%, the pygmy wood mouse for 32%, and other species for 15.4%. The autumn abundance of the bank vole was 4.6±1.8 and 18.9±2.6 ind./100 trap-days for 1991–1999 and 2000 – 2018, respectively; that of the pygmy wood mouse was 2.1±1.9 and 18.9±2.6 ind./100 trap-days, respectively. Since 2000, the peak amplitude of the bank vole number has increased by 1.1– 2.5 times, that of the pygmy wood mouse has increased by 2.5–4.2 times. Since 2006, the number peaks of these rodents began to repeat after 2–3 years. Over eighteen years (2000–2018), the autumn abundance of the bank vole twice (2008 and 2017) reached its peak values, at which the reproduction of voles ceased in July or early August. The correlation coefficient of the autumn abundance of the bank vole and pygmy wood mouse for 1996–2018 was 0.64±0.1. The spring abundance of the pygmy wood mouse has begun to more often exceed the spring abundance of the bank vole. Changes in the population cycles of the bank vole and pygmy wood mouse were obviously associated with some climatic features of the recent decades.