Home – Home – Jornals – Contemporary Problems of Ecology 2018 number 1

One of target regions of a worldwide network GLORIA (Global Observation Research Initiative in Alpine Environments) has been installed in the Katunskiy Biosphere Reserve (Central Altai) for revealing influence of climate changes on the plant diversity of alpine ecosystems during recent decades. The target region consists of 4 mountain summits selected according to the altitudinal gradient from the subalpine to the upper part of the alpine ecotone (2181, 2231, 2358, 2475 m.a.s.l.). Between 2005 and 2015, species in the target region shifted their distributions to higher altitudes by 5.3 м on average. Plant species richness increased on three higher summits and decreased on the lower summit.

Quantitative and qualitative characteristics of cones and seeds, the emergence and survival of seedlings of Siberian larch ( Larix sibirica Ledeb.) were studied in the different parts of the ecotone of the upper boundary of woody vegetation (treeline ecotone) on Mt. Serebryansky Kamen’ (the Northern Urals) and the hills (with land mark 312 m above sea level) in the vicinity of Mt. Chernaya (the Polar Urals) in the period from 2005 to 2011. A decrease in parameters of cones, the number of seeds in the cones and their viability in laboratory with increasing altitude as well as differences in quantity of seedlings between parts of treeline ecotone were revealed. It is shown that the formation of generations of Siberian larch in the Northern Urals occurs only after the productive years. It is noted that in the Polar Urals Siberian larch produces great seed crop every 2-3 years. It has been proved that seed production and death of seedlings of Siberian larch are influenced not only by air temperature and soil moisture, but also by the wind load, snow depth and soil temperature rapidly changing along the slope.

Climate changes induced migration of Siberian silkmoth ( Dendrolimus sibiricus Tschetv., one of the most dangerous pest in taiga) outbreaks northward. The initial outbreak of the Siberian silkmoth began in 2014 in the Siberian pine-fir stands within the Yenisei plain on the south-west gentle slopes at elevations up to 200 m above sea level. Later on, the outbreak extended to the forest with higher humidity, northern slopes and Yenisei Ridge low and middle elevations. The limit of the outbreak zone shifted up to 50 km (to 60^о26' N) northward from the historical boundary of formerly observed outbreaks. The outbreak was incited by increasing aridity and sum of positive temperatures ( t > +10 ^оC), and decreasing top soil moisture, and extended to the area up to 800,000 ha. Stands mortality was accompanied by activation of the secondary pests, including aggressive bark-beetle species Polygraphus proximus. The studied outbreak is a part of the pan-zonal outbreak which occurred in 2014-2017 on the territory of Siberia (Krasnoyarsk Krai, Tomsk, Kemero and Irkutsk Oblasts). The observed increase of warming, aridity and vegetation period extension open opportunities for Siberian silkmoth migration to the northern darkneedle taiga.

This article provides quantitative evaluation of aspects of the spatial heterogeneity of soil- and vegetation cover of floodplains in relation to the microrelief. Floodplains in the delta of the Northern Dvina River are given as examples. The study manifests that soil- and vegetation cover is a feature of the relief and related to it in various aspects. Floodplain meadows are proven to be reliefoid (specific component of the outer shell of the ground surface to which morphological description can be applied) at the micro scale level. In this study we refer to heterogeneity as to a difference in edaphic background caused by geomorphologic features of the river delta area in conjunction with various aspects of economic activity, and corresponding to the cluster of specific properties of vegetation. Due to intrazonal localization of floodplain ecosystems, the results of local survey, for example, in Arkhangelsk Oblast of Russia, can be extrapolated to other regions. Relevance of this research of heterogeneity of soil- and vegetation cover is based not only on fundamental aspects, but also on agricultural management needs.

The distribution of zooplankton in the pond, the entire area of which is occupied by phytocenoses with the dominance of plants from different ecological groups was studied. It was shown that in the phytocenosis of the submerged hydrophyte Elodea canаdensis zooplankton was included in the classical grazing food chain and algophages prevailed in the community. In the phytocenosis of the emergent plant Carex riparia zooplankton was connected to a greater extent with the links of the “microbial loop” and predators and bacterio-detritophages developed abundantly in the community.

The spatial distribution and seasonal dynamics of heterotrophic bacterioplankton production were studied and the value of autochthonous sources of substrates for bacteria was evaluated in the pelagic zone of the meso-eutrophic Rybinsk Reservoir (the Upper Volga). During the vegetation period the bacterial production ranged from 32 to 1352 (on average 444 ± 44) mg C/(m2 day). The total input of organic carbon from the processes of extracellular production of phytoplankton, viral lysis of prokaryotic cells, and untidy feeding of protists provided 9-64 % (on average 32 ± 3 %) of the daily carbon demand of heterotrophic bacterioplankton.

Dynаmic of changes HSPs70 amount and products’ of liрid peroxidation by hyperthermia of the laboratory culture of freshwater pulmonаte mollusk Stagnicola corvus (Gmelin, 1791) were evaluated. It was concluded that the impact of acute hyperthermia led to activation of stress adaptation mechanisms in S. corvus which was expressed in increasing of HSPs70 amount and decreasing the level of LPO products.

As a result of direct measurements, the phenomenon of tree stem rotation of Pinus sylvestris L. and Picea obovata Ldb. during the vegetation period has been established and described. On five trial plots located in different forest-growing conditions, the occurrence of the phenomenon, the magnitude and direction of turns, and their dynamics were studied over two years. Average values of rotation angle are 0.2-0.5, the maximal ones are 1.3-1.7. These characteristics are dependent on weather conditions of the year and forest types. On the following year more than half of trees change the direction of rotation to the opposite one, and 8-19 % of pine trees keep it. Based on the analysis of published and obtained data, a qualitative model of morphogenetic processes which explains the mechanism of the phenomenon described is proposed.

Changes in a complex of biochemical indices reflecting the disturbance of the homeostatic state and the activity of the adaptive reactions of Pinus sylvestris L. under conditions of technogenic pollution were studied. A number of parameters attest to the degradation of the physiological state of trees growing under conditions of excessive accumulation of pollutant elements: decrease in the ratio of protein and nonprotein nitrogen fractions in the needles by 52 %, decrease in the total phosphorus and its acid-soluble fraction by 40 and 63 %, respectively, reduction of carbon concentration by 31 %, decrease in the amount of chlorophyll a based on the weight of one needle by 23 %, chlorophyll b by 40 %, carotenoids by 42 %. The activation of defensive reactions of pine can be judged by increase in the amount of ascorbic acid in needles by 48 %, the amount of water-soluble phenolic compounds by 29 %, increase in the ratio of Chl. а /Chl. b - by 35 %, the ratio of green pigments to yellow - by 40 %, the level of water- and alcohol-soluble proteins by 40 and 30 %, respectively. The highest activity of biochemical defensive components was recorded in trees growing near the Shelekhov Industrial Center, in the emissions of which the content of fluorides and polycyclic aromatic hydrocarbons (PAHs) is high.

The changes in morphological characteristics of leaf and elemental composition of the above-ground organs of Potentilla fruticosa L. plants growing in the conditions of transport and industrial pollution in Novosibirsk were analyzed. The content of heavy metals - iron, nickel, vanadium and titanium in the above-ground organs of plants of street plantings increased by 1.3-9.5 times compared with the control. In response to the technogenic effect the size of the leaf assimilative organs decreased, and the value of fluctuating asymmetry index of the leaf terminal lobe compared to that of the background P. fruticosa plants increased. According to this index, environmental quality of the urban zone corresponds to the high level of pollution, of the background one to the low level.

Based on a multi-year research (1993-2016), an assessment of the state of the environment in the area of development of oil and gas condensate fields in the north of Western Siberia (YaNAD) is given. The content of petroleum hydrocarbons, PAHs and heavy metals (Cu, Zn, Fe, Pb, Cd, Ni, Co, Cr, Ba, Cd and Mn) was determined in soils, natural waters, bottom sediments and in indicator plants - Larix sibirica , Betula nаnа , Salix lanаta , Ledum decumbens , Vaccinium vitis-idaea , V. uliginosum and Cladonia alpestris. Using the calculation of the coefficients of interspecies conjugation of plants, pleiads of species corresponding to the ecological conditions of habitats and the intensity of the technogenic impact were identified. A set of indicators for assessing the transformation of natural complexes under the influence of oil and gas extraction is proposed.