Synanthropization and species diversityof floodplain ecosystems of the Ob-Irtysh basin, Russia

Currently, the phytocenoses of the Irtysh floodplain are experiencing intense anthropogenic pressures due to the intensive development of the oil and gas industry, as well as the urbanization of the territory. This paper focuses on the structure and species composition of the 27 studied areas in the floodplain ecosystems of the Ob-Irtysh basin. As a result of the research, we found 111 species of vascular plants from 33 families in plant communities. The areas belong to meadows and forest vegetation are represented by (1) birch forests (33%), (2) pine forests (10%), (3) fir forests (8%), (4) aspen forests (4%) and (5) associations of meadows (45%). Furthermore, we conducted a comparative analysis of the studied phytocenoses according to the Drude scale. To determine the anthropogenic transformation of the flora and individual plant communities, we determined the synanthropization index (the ratio of synanthropic species to the total number of species). In the synanthropic flora fraction, we distinguished 45 species belonging to 12 families, with the most multispecies being Apiaceae, Scrophulariaceae, Compositeae, Ranunculaceae, Poaceae, Fabaceae, Plantaginaceae. The synanthropization index of the studied phytocenoses ranges from 6.6% to 81.2%. The largest number of synanthropic species occurs in meadow associations, the content of synanthropes is greater than 50%, the structure is becoming more superficial, and the productivity and stability of plant communities are changing. The study of the horizontal structure of grass stands of meadow phytocenoses makes it possible to find the variability of different years, the change of dominant species and the stability of the species composition. Currently, researchers are paying considerable attention to the analysis of the structure of the herbage, since its study is of great theoretical and practical importance in clarifying phytocenotic relations.

Ecological-floristic characteristics of the specially protected natural area «Kostinskie Loga» (Samara Region)

The paper considers ecological-floristic characteristics of the specially protected natural area Kostinskie Loga, located in the southern part of the Samara Region (Bolshechernigovsky and Bolsheglushitsky Districts). The research area belongs to the subzone of fescue-feather grass steppes. The flora is represented by 240 species of vascular plants belonging to 160 genera, 49 families, 2 classes and 1 division. Ecological-cenotic analysis was used to assess the ecosystem diversity of the nature sanctuary. The leading groups for phytocenotic affinity are identified: steppe (65 species; 27,1%) and meadow-steppe (54 species; 22,5%), which indicates a good preservation of steppe biomes and demonstrates landscape features of the nature sanctuary. The low value of the synanthropization index (15,8%) reflects a moderate level of anthropogenic load. The adventive component of the flora is represented by 30 plant species (12,5%), among which the degree of naturalization is dominated by epecophytes (10,8%), the time of introduction by neophytes (6,7%), the methods of introduction are dominated by xenophytes (27 species; 11,3%). The analysis of flora identified 6 species included in the Black book of Central Russia (Acer negundo, Atriplex tatarica, Cyclachaena xanthiifolia, Hordeum jubatum, Elaeagnus angustifolia, Xanthium albinum). The introduction of alien plants into natural communities occurs due to pasture digression in areas bordering the territory of the nature sanctuary. In general, the degree of anthropogenic transformation of the flora in most of the territory is expressed slightly, the vegetation cover retains natural features inherent in the steppe zone. A high degree of preservation of steppe communities with a significant participation of rare representatives of flora (14,6%) creates prerequisites for the organization of one of the steppe reserve sections of the Samara Region.

Diversity of bird communities of the forest in the Boyarska experimental station at the gradient of anthropic load

Bird communities was researched according to the transect method in the nesting period of 2013 and 2015. 4 model forest plots in the Boyarskaya Experimental Station were selected. All of them are culturelphytocenoses based onPinus sylvestris L., Quercus robur L., Q. rubra L. The species composition of birds, their abundance, α-diversity indices, synanthropization index of bird communities (to Jedryctkowski) were analyzed. The similarity of bird communities was determined using cluster analysis in "Origin Pro 9.0". 65 bird species of 11 orders were recorded. 35 species of them live in the species reserve. On model plots that not have conservation status, the number of species in bird communities is 20–27. In plots with a dominance of Q. robur, 42 species were recorded, with a dominance of P. sylvestris - 35 species of the birds. Dominants in bird communities Parus major L. and Fringilla coelebs L. The presence in the list of subdominants Anthus trivialis L. and Phylloscopus sibilatrix Bechstein is a positive characteristic of the forest. The synanthropic of bird communities increases according to the increase in anthropic load: the synanthropization index from 0.4 to 0.65, the relative abundance of synanthropic birds in communities from 0.66 to 0.81. There are no alien birds. The species diversity and the number of bird species in the communities decreases along the gradient of increasing anthropic load. The similarity of bird communities and their α-diversity depends by the anthropic load, and not by the ratio of the species composition of the forest trees. The distribution of relative abundance of species in bird communities, on the contrary, is associated with the ratio of the species composition of trees. In forest plots dominated by P. sylvestris, bird communities are balanced, in plots with a predominance of Q. robur, disturbances in the development of bird communities are noticeable.

The impact of power lines on phytocenoses of the regional reserve “Uporovsky”, Tyumen Region, Russia

The article reflects the results of anthropogenic impact on phytocenoses of the territory of the Uporovsky regional nature reserve (Uporovsky district, Tyumen region, Russia). On the territory of the Uporovsky regional nature reserve (Uporovsky district, Tyumen region) there is a 110 kV electrical power transmission line (power line) which has the length of 8 kilometers and the right-of-way width of about 30 meters. This power line is undoubtedly the main source of anthropogenic electromagnetic radiation in this area. The degree of participation of individual species in the herbage was determined by taking into account their relative abundance. When exposed to the power lines in the right-of-way area, flora biodiversity decreases due to the loss of a number of species. The effect of electromagnetic fields causes transformation of the vegetation cover, synanthropization and the subsequent complete destruction of natural vegetation. To determine the degree of anthropogenic load on the studied phytocenoses, the synanthropization index is determined. In the synanthropic fraction of the flora, 30 species belonging to 12 families were identified. The synanthropization index of the studied phytocenoses ranges from 6.6% to 81.2%. The largest number of synanthropic species is observed in the anthropogenic area.

CHARACTERISTICS OF CHEMICAL COMPOSITION OF UPPER HORIZONS OF SOILS OF ROADSIDE PHYTOCENOSIS

Geobotanical descriptions of roadside phytocenoses of south of the Tyumen region were made within the boundaries of five administrative districts: Uporovsky, Zavodoukovsky, Yalutorovskiy, Yarkovsky, Tobolsk. Soil cuts were taken at each site and their morphological and chemical characteristics were determined. The biogenic composition (nitrite nitrogen, nitrates, mobile phosphorus compounds, exchange ammonium), the degree and type of soil salinization have been determined. The investigated soils, in accordance with the taxonomy of A. G. Dyukarev, belong to sod podzolic and podzolic types, typical subtype, ordinary genus. As for degree of salinity, soils are non-saline. Type of salinity is chloride-sulfate, sulfate. The reaction of the aqueous extract medium is weakly acidic. Biogenic elements determined during the study are concentrated to a greater extent in the upper horizons of the soil and are characterized by a low degree of availability of available phosphates in all areas from 28 to 50 mg/kg (movable forms). The nitrate content in all areas is in the same range, from 0.2 to 0.8 mg/kg. Distribution of ammonium metabolic (4.5-23.6 mg/kg), nitrates vary from 0.2 to 0.8 mg/kg. The content of nitrite nitrogen in all soil samples is minimal: less than 0.037 mg/kg of soil. The investigated phytocenoses are characterized by poor and stable floral composition. Most of the total projective cover of studied phytocenoses account for synanthropic species. Synanthropization index of the flora of the studied phytocenoses lies within 43-64%.

Assessment of the degree of synanthropization of vegetation in the urban lakes in Ostróda (Masurian Lake District)

Analyses were carried out of the structural and spatial character of the littoral vegetation in four urban lakes in Ostróda: Jakuba, Morliny, Kajkowskie and Perskie. Phytosociological studies made it possible to distinguish 20 phytosociological units representing plant communities from the classes: <em>Potamogetonetea</em> and <em>Phragmiteta</em>. The extent of anthropogenic changes in the littoral vegetation was examined using synanthropization index calculated for individual lakes. According to the classification proposed in the methods, Lake Morliny was classified as a natural reservoir, Lake Kajkowskie as belonging to the group of synanthropic water bodies (these two lakes were within the series of harmonic development). The other two lakes were classified as anthropogenic, characterised by disharmonic development due to high trophy. These results were confirmed by data on the area occupied in the lakes by particular alliances: <em>Potamogetonion</em>, <em>Nymphaeion</em>, <em>Phragmition</em> and <em>Magnocaricion</em>.