Analysis of meiotic chromosome aberrations in Siberian spruce (Picea obovata Ledeb.) under conditions of natural and technogenic stress

Meiotic abnormalities have been studied in Siberian spruce growing in the Southern Urals under different ecological conditions: in contrasting natural landscapes (high mountains, plains, river valleys and floodplains), in zones of natural geochemical anomalies, and in areas with different levels of industrial pollution. The results provide evidence for an adverse effect of technogenic pollution and extreme environmental factors on the process of microsporogenesis in the species studied.     

Distribution of Fine Roots of Coniferous Trees over the Soil Profile under Conditions of Pollution by Emissions from a Copper-Smelting Plant

The distribution of fine conducting roots of Siberian spruce, Siberian fir, and Scotch pine over the soil profile was studied in the taiga ecosystems polluted with heavy metals and SO₂. Under conditions of heavy pollution, tree roots were not found in the forest litter. Regardless of the level of technogenic load, the largest amount of conducting roots concentrated in the upper layer of mineral soil.     

Ecophysiological Responses of Larix sibiricaLedeb. and Pinus sibiricaDu Tour Undergrowth to Climate Change

The effects of probable climate change—an increase in atmospheric CO₂(by two times), air temperature, precipitation—on CO₂exchange and temperature dependence of net photosynthesis in the larch and Siberian stone pine undergrowth formed in the light larch forests of West Siberia were studied in chambers with an artificial climate. The change of the aforementioned ecological factors caused an increase in the temperature optima of photosynthesis and the range of optimum temperatures (in the case of Siberian stone pine, to a slightly greater degree). Therefore, the ranges of both species may broaden, and the Siberian stone pine can expand to the north, displacing larch tree stands.     

Morphophysiological responses of Pinus sylvestris L. and Picea obovata Ledeb. to industrial pollution under conditions of Northwestern Russia

Morphophysiological parameters of needles have been studied in Scots pine (Pinus sylvestris L.) and Siberian spruce (Picea obovata Ledeb.) trees of different life states growing under conditions of industrial air pollution with sulfur and heavy metals. Three functional clusters (tentatively named the initial, transitional, and disastrous clusters), each characterized by a certain metabolic status, have been revealed, and their quantitative and qualitative structure has been evaluated. The morphophysiological responses of pine and spruce are shown to be qualitatively different, depending on differentiation of trees with respect to vitality under conditions of industrial pollution. Probable factors accounting for these differences are discussed.     

Specific features of the allozyme structure of dandelion populations under conditions of radionuclide and chemical contamination

A study of allozyme spectra has been performed in dandelion cenopopulations growing for a long time under conditions of chemical pollution (the zone of the Nizhnii Tagil Metallurgical Plant, NTMP) or radioactive contamination (the zone of the Eastern Ural Radioactive Trace, EURT). Cenopopulations from the NTMP and EURT zones and from the background area differ significantly in the qualitative and quantitative composition of allozyme phenes. An analysis of clonal diversity has shown that all cenopopulations are phenogenetically unique. The genesis of each cenopopulation proceeded in a specific way: they had different sets of progenitor plants, whose descendants varied genetically in the course of their reproduction and more or less successful colonization of habitats, undergoing selection under the impact of natural environmental factors and technogenic stress. An increased variability of enzyme systems, compared to the sample from the background area, and, as a consequence, reduced clonal diversity may be regarded as a trait common to populations exposed to chemical or radiation stress.     

Structure and formation of conifer stands in the upper timberline ecotone on the North Chuya Ridge,Central Altai

The structure of Siberian stone pine (Pinus sibirica Du Tour.) and Siberian larch (Larix sibirica Ledeb.) stands and specific features of their formation have been studies in the forest-tundra ecotone on the North Chuya Ridge (2235–2475 m a.s.l.). Changes in the structure of these stands along the transition from the upper boundary of closed forests to the high-mountain tundra have proved to have an ambiguous pattern. Both tree species form mixed clusters of similar-aged trees in the lower part of the ecotone but grow singly, in scatters, in its upper part. The formation of conifer stands (tree clusters) in the lower part of the ecotone, on the slopes of the Aktru River valley, began during climate warming in the second half of the 19th century. The expansion of confers to its upper part took place markedly later, in the early 20th century (Siberian larch) or even in the 1930s (Siberian stone pine).     

Heavy metal accumulation by freshwater hydrobionts in a mining area in the south of the Russian Far East

The contents of heavy metals (HMs) were studied in freshwater hydrobionts from the south of the Russian Far East, including the area of wastewater discharge from a lead smelter (the village of Rudnaya Pristan, Primorye). The results showed that most invertebrates disappeared from the ecosystem as the toxicity of the aquatic environment increased. Mollusks of the genus Lymnaea proved to be most tolerant of HM pollution. As the contents of Pb, Mn, Cd, and Zn in bottom sediments increased, the amounts of these metals in mollusk bodies increased as well but to a much lesser extent, with the intensity of HM accumulation decreasing at their higher concentrations in the environment. The range of HM concentrations accumulated in the bodies of limneids noticeably broadened with an increase in technogenic impact. This is evidence for differences in the efficiency of mechanisms regulating the contents of trace elements in individuals of the same species under conditions of extreme pollution.     

Impact of urban anthropogenic pollution on seed production,morphological and biochemical characteristics of chamomile,Matricaria chamomila L.

It has been shown that the growth of technogenic dust pollution is accompanied by the accumulation of heavy metals in soil and plant phytomass, compared to the control, and that the morphometric and reproductive characteristics of Matricaria chamomila are most sensitive to the impact of these pollutants. The response of plants is manifested in increased variation in morphological characters, mobilization of compensatory protective biochemical mechanisms, and production of more viable seed progeny.     

Formation of Two Xylem Frost Injuries in One Annual Ring in Siberian Spruce under Conditions of Western Siberian Forest-Tundra

The phenomenon of the formation of two damaged xylem layers in one frost ring is described in Siberian spruce grown in western Siberian forest-tundra. Temperature conditions providing for the formation of pathological cell and tissue structures are determined. The relationship between the formation of double frost injuries and cold periods is demonstrated.     

Lipid peroxidation rates in <Emphasis Type="Italic">Taraxacum officinale</Emphasis> Wigg. and <Emphasis Type="Italic">Vicia cracca</Emphasis> L. from biotopes with different levels of soil pollution with heavy metals

The rates of lipid peroxidation (LPO) have been studied in Taraxacum officinale Wigg. (Asteraceae) and Vicia cracca L. (Fabaceae) from urban ecosystems with different levels of soil pollution with heavy metals (HMs), including Pb, Zn, Cu, and Cr. The former species responds to the increased HM contents by intensification of LPO processes, with their parameters correlating with the concentrations of Pb, Zn, and Cu in the soil. In the latter species from the same biotopes, conversely, LPO homeostasis remains actually undisturbed.     

Variability of the Integrated Biochemical Index in Fish Exposed to Technogenic Water of Mining and Ore-Processing Works

The hazard presented to aquatic animals by technogenic waters from mining and ore processing works, with an abnormally high potassium content and alkaline pH, was studied in experiments with fish using the integrated biochemical index (IBI) allowing an aggregate estimation of changes in the animal organism. The results showed that the IBI value directly depends on the extent of technogenic pollution, as well as on the species and age of fish.     

The ecology of bilberry (Vaccinium myrtillus L.) and cowberry (Vaccinium vitis-idaea L.) in Western Siberia

The data on the ecology of bilberry and cowberry in the West Siberian Plain, Kuznetsk Ala Tau, and highland Altai are presented. Ecological ranges of these plants and amplitudes of their tolerance for some environmental factors are described.     

Effect of Climatic Changes on Radial Increment and Age Structure Formation in High-Mountain Larch Forests of the Kuznetsk Ala Tau

The relationship between growth indices and renewal rates of the Siberian larch (Larix sibiricaLedeb.) stands that have grown at the timberline in the Kuznetsk Ala Tau mountains during the past 350 years was analyzed. The age generations of larch were formed in the 1640s, 1660s, 1680s, 1700s, 1720s, 1740s, 1760s–1770s, 1800s–1810s, 1850s, 1870s–1880s, 1900s, 1920s, and 1930s–1940s. It was shown that the formation of these age generations coincided with 10- to 30-year periods of increased growth of larch and improved temperature conditions in summer.     

Tree vegetation of the forest-tundra ecotone in the Western Sayan mountains and climatic trends

Parameters of reproduction of the Siberian stone pine (Pinus sibirica), including radial and apical tree increments, the age structure of stands, the amount of young growth, and its distribution along an altitudinal gradient, have been studied in the forest-tundra ecotone of the Western Sayan. The results show that, over the past 30 years, P. sibirica undergrowth has expanded to the mountain tundra belt, the apical and radial tree increments and stand density have increased, and the life form of many P. sibirica plants has changed from prostrate to erect (single-or multistemmed). These changes correlate with the dynamics of summer temperatures and monthly (in May and June) and annual precipitation. The rise of summer temperatures by 1°C promotes the expansion of P. sibirica undergrowth for approximately 150 m up the altitudinal gradient.     

Assessment of the Antioxidant Potential of Plants in Urban Ecosystems under Conditions of Anthropogenic Pollution of Soils

The leaves of 22 woody and herbaceous plant species growing in urban ecosystems of Kalinigrad were analyzed for the total contents of water-soluble antioxidants (TAC) and polyphenol contents. The soils of test plots were assayed for lead contents in the accumulative horizon. A significant excess over the background Pb level was revealed in soil samples from residential and industrial/utility areas (42% of the city territory), and TAC in plant tissues was found to decrease with an increase in Pb concentration in the soil. The role of polyphenols in forming the antioxidant potential of urban plants growing under conditions of technogenic soil pollution was evaluated. Based on cluster analysis of the water-soluble antioxidant and polyphenol accumulation patterns, the plants were classified into four groups. The results of this study may be used for comprehensive assessment of the resilience of urban plants to anthropogenic impact and improvement of the approaches and methods for monitoring industrial pollution in urban areas.     

Morphogenesis of the Procumbent Life Form in Siberian Stone Pine at the Timberline in the Western Sayan Mountains

The morphology and development are described for Siberian stone pine (Pinus sibiricaDu Tour) growing at the timberline in the Western Sayan Mountains. Throughout ontogeny, these plants have a short stem trailing in an approximately horizontal direction. Maximal longevity and viability are characteristic of basal branches, which are able to root and produce vegetative generations. This allows these plants to be classified with the procumbent tree life form, in which the clones of most adaptive genotypes not only survive under extreme environmental conditions, but can also reproduce vegetatively.     

On the effect of climate on the morphological structure of <Emphasis Type="Italic">Alnus hirsuta</Emphasis> (Betulaceae)

An analysis of correlations between metric leaf characters and climatic parameters of habitats in the Siberian alder (Alnus hirsuta) has shown that phenotypic variation in this species depends on the gradient of climatic factors and that the morphological structure of the species is largely determined by variation in climatic conditions within the species range.     

Ecophysiological indicators of the state of animal populations exposed to damaging factors

Indices of abundance and reproduction rate are considered in some groups of aquatic and terrestrial vertebrates from the zones of technogenic disasters. Upon a critical population decline caused by external destructive factors, such as emissions of acute ecotoxicants, the ecophysiological and behavioral compensatory mechanisms are activated, which provide for restoration of the total population size to the optimum within a short period of time. Environmental pollution with substances disturbing the reproductive function has the gravest consequences for animals. In this case, population size may remain fairly high, and, therefore, the effect of enhanced reproduction as a response to population decline does not take place, which eventually leads to a gradual but irreversible destruction of the population. Pathologies of reproduction should be used as a criterion for assessing the state of animals in the zones of technogenic disasters.Translated from Ekologiya, No. 1, 2005, pp. 32–38.Original Russian Text Copyright © 2005 by Shilova, Shatunovskii.     

Ecology of Siberian stone pine (Pinus sibirica Du Tour) and Siberian larch (Larix sibirica Ledeb.) in the Altai mountain glacial basins

Data are presented on the ecology of Siberian stone pine and Siberian larch in recent Altai mountain glacial basins at elevations above 2100 m a.s.l. The representative example of the Aktru basin is used to demonstrate the ranges of tolerance of these tree species to a series of ecological factors.