Soil Saprotrophic Microfungi Associated with Roots of Calamagrostis epigeios on an Abandoned Deposit of Toxic Waste from Smelter Factory Processing Pyrite Raw Materials

Saprotrophic microfungi associated with roots of Calamagrostis epigeios growing in industrial waste contaminated with high concentrations of heavy metals (manganese, iron, zinc) were isolated on three different media. The isolates were obtained from three plots colonized by plant cenoses, representing three different succession series of plant cover: initial, intermediate, and advanced. A total of 60 species of saprotrophic microfungi were found in the roots during three samplings. In addition, unidentified dark and white sterile mycelia were frequently isolated. Trichoderma koningii was frequent in the roots formed under the advanced phytocenose. The abundance of dark sterile mycelium gradually decreased with progressing succession of the plant cover. Chrysosporium merdarium was rarely observed in the roots under the intermediate and advanced plant cenoses. Multivariate redundancy analysis showed that the effect of succession stage of phytocenoses on incidence of saprotrophic microfungi in mycocenoses present in roots was statistically significant. When the similarity of root mycocenoses of the three plots was studied using the similarity coefficients, the results proved that the similarities between the initial and intermediate or intermediate and advanced mycocenoses were higher than that between the initial and advanced mycocenoses. This corresponds to a different speed of succession of the mycocenoses. The results suggest that the dark sterile mycelia, abundant at slowly developing plots, play a dominant role during the first stages of succession where the plant cover is poor.     

Study of interactions between wild soybean subpopulations (<Emphasis Type="Italic">Glycine soja</Emphasis>) in the valley of the Tsukanovka river in the south of Russia’s Far East

Comparative analysis of the genetic structure of natural and anthropogenic populations of G. soja gives significant information about the formation of different populations and allows for the developing of measures for the preservation of the unique natural gene bank of wild soybean, which is a species closely related to cultivated soybean. In this study, ISSR-markers were used to carry out a comparative analysis of the genetic structure of natural and anthropogenic subpopulations of G. soja for studying the possible mutual influence of subpopulations of anthropogenic and natural phytocenosis on the formation of their genetic diversity and studying the genetic structure of natural subpopulations of wild soybean in the contact places between the two types of cenoses. As a result, the characteristics that describe the genetic diversity of the studied populations have been identified, and the important role of interaction between subpopulations of different phytocenoses in the formation of the spatial genetic structure of the population in the Tsukanovka river valley have been demonstrated.     

Initial data on biological activity of taiga–steppe soils in the lower reaches of the Kolyma River

Microbiological and enzyme activities of extrazonal taiga-steppe soils in the lower reaches of the Kolyma River have been studied for the first time. Contrary to north-taiga cryometamorphic soils, predominating in the area, microbial cenoses under herb–sedge petrophytic and grass–sagebrush–herb thermophytic steppes are characterized by features typical for arid soils. The saturation of the soil profile with microorganisms is greater, and the development of actinomycetes is more intensive. The enzyme complex is characterized by high activity of dehydrogenases.     

Retrospective assessment of the dynamics of nitrogen availability in pine forests of the near-Moscow region based on the data of phytoindication

Earlier published data on the long-term geobotanic monitoring in permanent pilot plots have been used to analyze changes in trophic conditions and estimate nitrogen nutrition availability to pine forests of the Serebryanyi Bor Forestry located in the Moscow oblast. The assessments of habitats based on the ecological scales of soil richness with nitrogen, which were developed by D.N. Tsyganov and G. Ellenberg, and analysis of the dynamics of stenobiont species have revealed the properties of changes in the species composition and conditions of nitrogen availability to forests for the period from 1957–1961 to 2003. The results indicate increased nitrogen availability to forests in the studied period for all permanent plots, but reflect different intensities of the trend of eutrophication in different monitoring stages. A more intense growth in soil richness with nitrogen in all permanent plots was in the period since 1957–1961 to 1989–1990. In the next years, the level of nitrogen availability to phytocenoses almost did not change. The improvement in the trophic conditions was accompanied by the growth in total species richness and increase in the number of stenobionts with high requirements to nitrogen nutrition. The results from analyzing the dynamics of stenobionts confirm the division of the period under consideration into two stages. From 1957–1961 to 1989–1990, changes in the species composition of plant communities in the pine forests under consideration were similar but differed in intensity. From 1989–1990 to 2003 (against the background of total deceleration of the eutrophication trend), the similarity of species dynamics in the communities was disturbed. The impact of air pollution by NOx on nitrogen nutrition availability to forests was examined with consideration for the fact that the studied area is within the capital agglomeration. The dynamics of the intensity of air nitrogen deposition is in good agreement with the revealed changes in the species composition of phytocenoses and nitrogen soil richness. It gives reasons to suppose that the trend of forest eutrophication in the 1960s–1980s was strengthened by the impact of increased levels of atmospheric nitrogen deposition.     

Characteristics of Slow Induction Curve of Chlorophyll Fluorescence and CO2 Exchange for the Assessment of Plant Heat Tolerance at Various Levels of Light Intensity

The heat tolerance of wheat (Triticum aestivum L.) and radish (Raphanus sativus L. var. minor) cenoses exposed to elevated and damaging air temperatures (35°C for 20 h, 45°C for 7 h) under photoculture conditions at various levels of photosynthetically active radiation (PAR) was assessed by measuring characteristics of the slow induction curve of chlorophyll fluorescence at 682 and 734 nm and the CO₂ exchange rate. Irrespective of the illumination level, the exposure of the cenoses to 35°C did not induce irreversible changes in the plant photosynthetic apparatus. The lowest extent of damage to wheat and radish cenoses exposed to 45°C was observed at 150 W/m² of PAR, whereas the highest damage of the plants was observed at an illumination level that was close to the compensation point of the cenose photosynthesis (50–70 W/m² of PAR at air temperature of 24°C). Viability index proved to be the most sensitive characteristic, compared to other characteristics, which were determined by measuring the slow phase of fluorescence induction at 682 and 734 nm. In the cenoses studied, the pattern of changes in the viability index in response to a stress factor was close to the changes in the photosynthetic rate.     

Model estimates of climate change impact on habitats of zonal vegetation for the plain territories of Russia

Possible changes in the habitats of zonal phytocenoses for the plain territories of Russia under a 1°C increase in the annual mean global surface temperature are estimated by simulation with the atmosphere-ocean general circulation models ECHAM4/OPYC3 and HadCM3 and the intermediate-complexity climate model of the Institute of Atmospheric Physics for anthropogenic scenarios of greenhouse gas changes. The response of the phytocenotic habitats to possible climate changes is estimated from the changes in net primary production for the considered climatic scenarios. The obtained data allowed us to recognize the zonal phytocenoses most sensitive to climate changes.     

The use of aquatic vegetation in lake assessment: testing the sensitivity of macrophyte metrics to anthropogenic pressures and water quality

The relationships between aquatic vegetation, anthropogenic pressures and water quality in 83 Polish lowland lakes were analysed in order to select the best responding macrophyte metrics to be used in ecological status assessment. Several metrics describing the syntaxonomic composition, abundance and spatial structure of macrophytes were tested in three morphological lake types (deep regular-shaped, deep ribbon-shaped and shallow) separately by using the Spearman rank correlation coefficients. Among all the parameters tested, only some anthropogenic pressure parameters (the percentage share of urban areas and forests in a catchment, the pollution load from point sources) and all the water quality indicators (TP, TN, Chla, SD) were significantly correlated with most of the macrophyte metrics, although for different lake types the strength and significance of relationships varied substantially. The macrophyte metrics which best responded to anthropogenic pressures and water quality changes were: (i) in deep regular-shaped lakes: the percentage share of Chara phytocenoses and rush phytocenoses in the total phytolittoral area, the maximum depth of plant distribution and the colonisation index; (ii) in deep ribbon-shaped lakes: the hydrophytes/helophytes area ratio, the percentage share of submerged and rush phytocenoses in the total phytolittoral area; (iii) in shallow lakes: the percentage share of Chara phytocenoses and rush phytocenoses in the total phytolittoral area, and the hydrophytes/helophytes area ratio. These metrics can then be used when elaborating new or refining existing macrophyte-based methods of ecological status assessment.     

Zooplankton in Monospecies and Mixed Phytocenoses of <Emphasis Type="Italic">Stratiotes aloides</Emphasis> L. and <Emphasis Type="Italic">Sagittaria sagittifolia</Emphasis> L. under Experimental Conditions

Aquatic plants differing in morphology and metabolic products make unequal changes in the habitat of hydrobionts. The development of zooplankton in monospecies and mixed phytocenoses of the water soldier Stratiotes aloides L. and arrowhead Sagittaria sagittifolia L. has been studied in microcosms. In monospecies phytocenoses of different plants, the preferential development of one or another species of littoral Cladocera is found. The number of predators and species diversity increase in zooplankton as the spatial organization becomes more complex. Zooplankton in the phytocenosis, formed simultaneously by two species of plants, has features characteristic of monospecies phytocenoses, as well as its own peculiarities, primarily related to the development of euplankton species. It is assumed that aquatic plants indirectly affect zooplankton via changes in the quantitative ratio of different groups of food organisms.     

Isolation of tremelloid yeasts on glucuronate medium

D-Glucuronate-containing agar is suggested for evaluating the population density and diversity of tremelloid yeasts in natural cenoses. This medium is superior to the commonly used wort agar on which many representatives of tremelloid yeasts cannot be revealed.     

The Levels of Organization of the Photosynthetic Apparatus and the Control of Production Processes in Phytocenoses under Artificial-Light Culture

The processes limiting the production in higher plant phytocenoses under an artificial-light culture are analyzed in relation to the multilevel organization of the photosynthetic apparatus (PA). The authors consider the feasibility of overcoming these limitations by optimizing the physical parameters of irradiation (the structure of the light spectrum, the rate, and the ratio of radiation fluxes in photosynthetically active radiation (PAR) and infrared (IR) regions) at the molecular, leaf, plant, and cenotic levels of PA organization. To illustrate this approach, the authors used a complex experiment in an artificial ecosystem to evaluate the efficiency of the light control of production processes in multispecies phytocenoses by alleviating or removing the factors that limit plant production at the various levels of PA organization. An artificial-light culture is seen as an instrument for solving several problems of theoretical and applied plant physiology and related disciplines in the future.     

Post-pasture demutation in communities of the Ob forest-steppe

Influence of protection regime on natural degraded pasture areas at different stages of pasture digression was studied under the conditions of the right Ob riverside forest-steppe during the years 1994–2004. It has been revealed that the isolation of pasture phytocenoses of a steppe meadow from pasturing leads to an increase in the productivity of grass owing to different economic-botanical groups of plants. The increase in the productivity at the initial stage of digression is due to legumes and forbs, while at the final stages it is mainly due to increased mass of grasses. Removal of pasture load promotes the formation of intermediate communities; in this situation, an increase in their species diversity is to a high extent due to the adjacent floristically richer phytocenoses.     

Glucuronate media for isolating tremelloid yeasts

D-Glucuronate-containing agar is suggested for evaluation the population density and diversity of tremelloid yeasts in natural cenoses. This medium is superior to the commonly used wort agar on which many representatives of tremelloid yeasts cannot be revealed.     

Habitat requirements of the <Emphasis Type="Italic">Charetum intermediae</Emphasis> phytocoenoses in lakes of western Poland

The study presents habitat and phytosociological analyses of the Chara intermedia phytocenoses, rare described in Europe. 16 physico-chemical water parameters were analysed, coming from the samples taken in 20 phytocenoses of 13 lakes located in western Poland. The analysed community appeared in naturally shallow lakes representing last stages of the disappearance of glacial water basins. The study attempts to estimate the bioindicative value of the charophyta meadow Charetum intermediae in relation to its habitat. A particular attention has been paid to the determination of the habitat trophic condition, and to the concentration of elements connected with the hardness of water and the content of humic substances. The study shows crucial habitat gradients of the C. intermediae association, taking into account also the species composition of phytocenoses.     

Vegetation of the <Emphasis Type="Italic">Hydrochari-Lemnete</Emphasis> and <Emphasis Type="Italic">Potametea</Emphasis> classes in the Danube-Tisza-Danube hydrosystem (Serbia)

Aquatic vegetation of Hydrochari-Lemnetea and Potametea classes in the Danube-Tisza-Danube hydrosystem (Hs DTD) was studied in 2009–2012, by applying the standard Braun-Blanquet method. The canal network vegetation comprises 14 associations, with Trapetum natantis and Ceratophylletum demersi being the most widely distributed. Hs DTD is also a habitat for several important endangered species, which serve as edificators of the following phytocenoses: Nymphaeetum albae, Nymphaeetum albo-luteae, Nymphoidetum peltatae, Trapetum natantis, Lemno-Spirodeletum, Salvinio-Spirodeletum polyrrhizae, Lemno-Utricularietum vulgaris, Potametum nodosi, Myriophyllo-Potametum and Najadetum marinae. In the studied vegetation, we also found an invasive phytocenosis Elodeetum canadensis that did not have an expanding tendency, and Ceratophyllo demersi-Vallisnerietum spiralis that had this tendency, which made monitoring its stands necessary. Physico-chemical analyses of water, conducted at localities in which the studied phytocenoses thrive, revealed that the development and distribution of most phytocenoses is closely linked with specific habitat conditions. Among the studied parameters, the most significant for the phytocenoses differentiation were: pH, alkalinity, COD-MnO₄, BOD₅, NO ₃ ^? , NO ₂ ^? , PO ₄ ^3? and the concentration of total phosphorus.     

Soil and geobotanical profiling in phytocenotic studies at junctions of taiga and extrazonal steppes on the western shore of Lake Baikal

The formation of phytocenoses at the junction of taiga and extrazonal steppes has been studied in the center of the western Baikal lakeshore. Geobotanical profiling, including soil profiling, has been carried out in one of the key areas. The structure and dynamics of community formation in the conditions of interrelated development of light coniferous taiga and extrazonal steppes have been revealed. Edaphic conditions and location of phytocenoses are the main initiating environmental factors which determine the trend of floral cover development in this part of the western Baikal lakeshore.     

Biological characterization of ecovars of gram-negative bacteria circulating in the burn ward

In 44 isolated cultures of Gram-negative bacteria, besides commonly known pathogenicity factors, their adhesive activity towards the cells of the buccal epithelium and their interrelations with the representatives of normal microflora which determine natural resistance to colonization have been studied. The artificial adhesion of target cells is accompanied by the inhibition on the natural colonization of epithelial cells by Streptococcus salivarius; it is, therefore, evident that adhesiveness is one of the factors which determine the behavior of microorganisms in cenoses. The circulation of adhesive strains of Gram-negative bacteria has been noted in the burn ward.     

Impact of silkmoth outbreak on taiga wildfires

We provide a quantitative analysis of postoutbreak wildfire frequency within the confluence of the Yenisei and Angara rivers affected by the Siberian Silkmoth (Dendrolimus sibiricus Tschetv.). A catastrophic outbreak was observed in 1993–1996. It expanded to about 1 million ha and caused stand mortality on an area of about 460000 ha. For the outbreak area, the fire frequency was about 7 times higher when compared to the reference area; on the burned area, it was 20 times higher. The peak of fire activity within outbreak areas occurs in May–June, while that for undamaged coniferous stands is in July. The number of fires is correlated with the mean monthly air temperature (r = 0.65) of June. The area of fires displays a negative correlation with moisture conditions: precipitation (r =–0.53), drought index (SPEI: r =–0.57), and ground-cover moisture content (r =–0.57). Extensive fires prevail within outbreak areas (S > 1000 ha), while within the control there is a smaller area of fires. Multiple (reoccurring) wildfires are typical for pest outbreak areas. The area of these fires is related to their reoccurrence by logarithmic dependence (17% of the territory twice burned by forests fires, 5% on that burned three times, and 0.5% on that burned four times). Wildfires in the outbreak areas surpress the initial forest recovery by destroying the regeneration of conifers: 20 years after the outbreak, >90% of disturbed areas are occupied by grass–bush and small-leaved cenoses.     

Isolation of hydrocarbon-oxidizing psychrophilic bacteria from oil-polluted soils

Microorganisms growing on a mineral medium with crude oil and its light fractions as only carbon and energy sources have been isolated from samples of oil-polluted soils collected in the Usa District (Komi Republic, Russia). For the first time, hydrocarbon-oxidizing psychrophilic bacteria of the genus Cytophaga have been found that are clearly capable of consuming crude oil hydrocarbons. A method for cultivating microorganisms on porous plastic is proposed. The data from the literature on the response of soil microbiota to oil pollution indicate that the pollution can activate or suppress the growth of various physiological groups of microorganisms [1]. Different soil and climatic conditions and pollution levels can give rise to different microbial cenoses, which include different associations and predominant microbial species.     

Spatial Distribution of Zooplankton on the Upper Part of the Cheboksary Reservoir

The modern state of the species structure and spatial distribution of zooplankton cenoses in the upper part of the river hydraulics zone in the Cheboksary Reservoir, where the construction of a low-head dam is planned, and in the mouth part of the Oka River has been studied based on the data of 2016 and 2017. Two zooplankton communities have been identified in these areas; differences in their species structure are determined by several ecological factors: total mineralization, water transparency, temperature, pH, etc.