Home – Home – Jornals – Contemporary Problems of Ecology 2021 number 2

Ecological regularities of Urup island landscape differentiation of avifauna and bird population are analyzed. The data were obtained in the 2019 expedition during the survey of the southern part of the Great Kuril ridge. The research was conducted in the vicinity of Novokurilskaya Bay in the North-East and the vicinity of Shchukin Bay on the Van Der Lind Peninsula in the southwest of Urup island. The survey was carried out by the method of route accounting on transects of unlimited width at altitudes of 0-200 m above sea level. In 2019 90 bird species have been recorded: 59 on the North-East and 56 on the South - West of the island. The similarity coefficient of local avifauna of the surveyed points ( n = 2), obtained by the Sorensen formula - 68 %. 38 % of species are widespread, 41 % locally, and 21 % are isolated foci. Six species were registered for the first time. Taxonomic structure of Urup avifauna, formed by species of 12 orders, corresponds to the zonal and landscape features of island territories located near the North-Eastern Eurasia. The number of species represented is dominated by Passeriformes (39 %), Charadriiformes (28 %) and Anseriformes (10 %) characteristic of the Boreal and Hypo-Arctic zones of the Palearctic. The zoogeographic originality of the local avifauna is due to the combination of elements of the Far Eastern island, Pacifical, Siberian, Chinese faunal complexes, Siberian-American and widespread species, as well as Japanese island endemics. Local avifauna is formed in the system of general zonal-landscape and altitude-belt patterns combining ecological groups of marine, land and mountain species. Mountain specifics of the avifauna defines species ( n = 9) that are ecologically closely related to land or water-near-water elements of the alpine landscape over the entire area of their range or a significant part of it. The bird population density of land habitats is 323-609 sp/km² (on average - 466 sp/km²), on the coast and nearby sea area 774-2050 sp/km² (on average - 1412 sp/km²). The similarity coefficients of bird populations are 20 % in land-based habitats and 17 % in the coastal-marine habitats. Pacific Swift, Buff-bellied Pipit, Arctic Warbler, Eurasian Nutcracker, Grey Bunting dominate in the forest and bush habitats. Harlequin Duck, Glaucous-winged Gull, Black-legged Kittiwake, Pacific Swift, Buff-bellied Pipit, Black-backed (White) Wagtail dominate in the coast and the adjacent sea area. In open sea areas, the most common are Black-footed Albatross and Laysan Albatross, Northern Fulmar, Short-tailed Shearwater and Common Murre.

Seashore habitats of the Shokalsky Island (73є N) in the Kara Sea, Arctic Ocean, is shown to support at least 33 soil mite species, 7 of which predominate. We analyzed the species distributions in soil samples taken at three levels of marine marsh. Upon mite extraction, the following parameters were determined in soil cores: salinity, granulometric composition, carbon and nitrogen contents, and the condition of the plant cover. Both mite species diversity and total abundance increase from lower to higher marsh levels. CCA ordination revealed that the distribution of the mycetophagous littoral-dweller, Ameronothrus nigrofemoratus , depends on soil salinity. The distribution patterns of Svalbardia paludicola , Scutacarus offaliensis , Steneotarsonemus arcticus and two Arctoseius species seem to primarily be determined by drainage intensity through choosing sandy grounds. The distributions of the mite species that prefer the highest level of salt marsh depend first of all on either phytomass content (most species) or the concentration of major biogenic elements ( Nanorchestes cf. gilli , Eustigmaeus cf. tjumeniensis , Cheilostigmaeus longisetosus ) in soil samples. The CCA model accounts for 80.5 % dispersion of the data. A comparative analysis of the species structure of mite communities indicated the assemblage of the highest marsh level (with a considerable moss storey) as being the most diverse and special. The acarocenoses formed under different plant associations of distinct marsh levels (ass. Puccinellietum phryganodis and ass. Caricetum subspathaceae ), but on similar clay grounds appeared to be the most similar, this probably being due to close inundation times caused by drainage conditions.

The central part of the Kuril archipelago, and in particularly Urup Island, remains insufficiently studied due to poor accessibility of this practically uninhabited island and severe nature. Floristic subdivision of the southern part of the Kuril archipelago (Russian Far East) remains controversial. In 2019 we carried out floristic studies on Urup to collect additional data on the island flora to clarify its position in floristic subdivision. Moreover, several short botanical excursions on Iturup were made. The paper represents new data on distribution, habitats and population status of 28 native vascular plant species. Myriophyllum ussuriense was first discovered in the Sakhalin Region and proposed for inclusion in the regional list of rare species and regional Red Data Book. Four species ( Corallorhiza trifida , Pedicularis adunca , Salix arctica , Salix chamissonis ) were first revealed in the southern Kuril Islands. Besides, we found 8 species ( Carex livida , Eleocharis margaritacea , Epipactis papillosa , Juncus articulatus , J. decipiens , Neottia puberula , Poa austrokurilensis , Utricularia minor ) that are new for Urup. Moreover, we confirmed occurrence of Isoëtes asiatica , Hydrangea petiolaris , Rhynchospora alba , Salix fuscescens , previously known from Urup only according to literature. Our findings confirm that Urup belongs in the floristic subdivision of the Kuril archipelago to a transitional zone between the northern and southern Kuril Islands, where distribution areas of East-Asian and Boreal species overlap. New information on the distribution, habitats and population status of 14 threatened plant species protected in Russia and the Sahkalin Region is provided. Further study of the flora of the Kuril Islands and monitoring of rare and threatened vascular plant species are required.

Under human increasing activity in Arctic areas and in the face of global climate change the study of Arctic communities and ecosystems becomes more and more interesting. However the question of interspecific interactions’ impact in their transformation remains unresolved. The paper deals with a diet selectivity analysis of Wrangel Island lemming, goose and ruminant species, an estimation of the selectivity influence on their long-term community dynamics and the whole tundra ecosystem functioning. It was shown that the herbivore selectivity distribution mainly depends on their morphophisiology and that under equal conditions the lesser selective feeders become dominant with biodiversity increasing. We concluded that despite considerable human impact on the herbivore species composition their mainly endogenous dynamics of abundance distribution correspond to the ecological succession, in which the total herbivore biomass decreased by half, and their total consumption and likely the whole primary production into more than four times.

The paper provides an analysis of long-term data on the ecology of rodent and insectivorous mammalian communities of different altitudinal zones of the southern slope of the Munku-Sardyk ridge in Mongolia. A description of the fauna, population, and diversity of small mammal communities within different altitudinal zones is presented. It was shown that the composition and structure of the communities of high-altitude zones depend on the vertical distribution of plant associations, micro landscape, and ecological specialization of species in the community. Comparison of the diversity parameters of small mammal communities in mountainous altitudinal zones in adjacent territories in the Baikal region is given. A comparison of the mountain and lowland steppe rodent communities of Southern Siberia revealed a high similarity in the dominance structure of the communities of the Munku-Sardyk ridge and Tazheran steppe (Baikal region).

The overview deals with freshwater actinobacteria - one of the dominant groups of the heterotrophic bacterioplankton, with their biology and ecology, with their role in the cycling of some main biogenic elements and in the transformation of recalcitrant organic compounds in freshwater reservoirs. Distinguishing features of the most abundant groups of planktonic freshwater actinobacteria, methods of isolation, of obtaining pure cultures and of further cultivation are considered. General and individual ecophysiological, phenotypic, genotypic and metabolic characteristics are given.

The decomposition process in larch forests, which occupy a significant area of the boreal zone and are most often subjected to strong ground fires, remains poorly understood. In a long field experiment (850 days), we observed the decomposition of the dominant types of litter (needles, leaves, branches, grass) in natural and disturbed larch forests of the Russian Far East. We measured mass loss, the dynamics of carbon (C) and nitrogen (N), respiration, and environmental conditions (temperature and humidity). It was found that 15 years after a long-lasting surface fire, the supply of C and N with land litter decreased by 2,2 times compared to the pre-fire level. At this stage of post-pyrogenic succession, a decrease in the proportion of woody and an increase in the proportion of low lignin grass litter was observed. We did not find differences between the studied stands in the rate of mass loss for leaves, grass, and branches, while the needles in the post-pyrogenic larch decomposed more slowly than in the control in the later stages of the experiment (850 days: p = 0,0035). A lower intensity of respiration of decay needles on burns compared with the control ( p = 0,0207) and a decrease in the N content of decaying needles in the later stages of the experiment ( p = 0,0234) indicate inhibition of microbiological activity. A decrease in the total supply of N with litter in the post-pyrogenic stand, combined with a low decomposition rate of needles, restrains the release of N and its availability to plants and microorganisms, which may affect the restoration of the boreal larch ecosystem damaged by fire.

Spatial monitoring was carried out and the ecological situation was experimentally assessed in local populations of plants of the relict endemic species V. formosa , according to the climate modeling of the range carried out by the method of maximum entropy. Plants of this species live exclusively in the highlands on open ungrounded shale screes in the glacial zones and distributed sporadically in the mountain systems of Taurus, Armenian Highlands, the Caucasus and Elburz. V. formosa is a very rare species, as a result of which it is listed in the state Red Books of Russia, Azerbaijan and Armenia, as well as numerous regional Red Books. The limiting factors determining its rarity were not previously reliably established, which necessitated the assessment of the environmental situation at the same time at all points of growth of this species according to climate modeling. An original technique has been developed for assessing the environmental situation in and around localities, with the following gradations highlighted: favorable, unfavorable, and ambivalent. A quantitative method of such an assessment (in points) is proposed. As a result, the territories with the more favorable climatic conditions for local populations of V. formosa were identified. The ecological situations directly in localities were assessed as slightly favorable for 11 local populations, unfavorable for 23 local populations, and ambivalent for 36 local populations. Such technique for decoding the ecological situation around localities according to climate modeling is proposed here for the first time in world practice. It is aimed at obtaining the most accurate formalized information about the climatic situation in each locality and in each cell of the nest surrounding the locality, within the full range of the species. To formalize the description of a specific climatic situation, it is proposed to use the color scale of rasters generated in the MAXENT computer program. 1 point was assigned for loci that are under the influence of the negative complex of climatic factors (blue segment of the spectrum); 2 points for loci that are under the neutral influence (green segment of the spectrum); 3 points for loci that are under the positive (favorable) influence of climatic factors (yellow-red segment of the spectrum).

A five-year study was carried out to investigate the possibility of creating a nature-like community of meadow-steppe plant species with the dominance of Stipa capillata L. on an overburden dump at the Vinogradov coal mine (Kemerovo region). The preparation of the dump surface for revegetation consisted in spreading the technogenic eluvium and covering it with a 10 cm layer of fertile topsoil (TS), which was taken from soil heaps formed during the formation of the dump, or potentially fertile undersoil (US) represented by loess-like loams. The control was a horizontal section of a sandstone slope with a lithogenically under-developed soil layer without applying TS and/or US. An herbal-seed blend (HSB) was harvested during summer and autumn months on steppe slopes of the “Bachatskiye Sopki” regional botanical reserve, the vegetation of which included meadow-steppe plant communities dominated by S. capillata . Observations were carried out over 5 years during the 2015-2019 period. It was found that the growth and development of S. capillata was most pronounced in loamy soils. In such soils, individual plants begin to bloom during the 1st year, while all plants bloom and bear fruit in the 3rd year. The share of S. capillata in the total productivity comprised 83.6 % by the 5th year of observations. S. capillata plants form a powerful sod thus competing with weeds. In experiments with the application of TS, the share of S. capillata comprised 4-8 % from 2015 to 2018, increasing to 30.1 % in 2019. In this experimental site, suppression of individual S. capillata plants was associated with the highly competitive Elytrigia repens (L.) Nevski species, whose rhizomes were introduced to the site with the TS from soil heaps. In the control, an S. capillata community was formed during the 4th-5th year as a result of re-seeding from experimental sites.

Changes in the number of anaerobic microorganisms (denitrifying, sulfate and iron-reducing) in ground and groundwater polluted with oil products were investigated when bioremediation was carried out. It was shown that in the studied geological media the number of psychrophilic microorganisms of anaerobic groups (denitrifying, sulfate and iron-reducing, as assessed by the number of the colony-forming units on the respective cultivation media) was higher than the number mesophilic ones. When N, P, K-fertilizers were introduced into the contaminated zone, the number of psychrophilic microorganisms changed more significantly, both increasing and decreasing. When the ground in the aeration zone was treated, the number of anaerobes decreased, probably due to competitive displacement by aerobes. The number of hydrocarbon-oxidizing and ammonifying microorganisms increased by an order of magnitude and amounted to 10⁶ CFU/g and 10⁶-10⁷ CFU/g, respectively. When fertilizers were added to groundwater, the number of anaerobic microorganisms increased by 1-4 orders of magnitude, the number of denitrifiers reached 10⁵ CFU/ml, whereas the CFU number of sulfate-and iron-reducers was 10³-10⁴ and 10²-10³ CFU/ml, respectively. It was revealed that simultaneously with increase of the CFU numbers some chemical properties changed indicating intensified biodegradation of petroleum products. In particular, an antiphase changes in the ammonium and nitrate concentrations were observed due to the decomposition of petroleum products, nitrification and denitrification, as well as the concentration of bicarbonate and sulfate ions due to sulfate reduction.