Specific Features of Root System Structure in Pinus sylvestrisL. and Larix sukaczewiiDyl. under Conditions of the Ufa Industrial Center

Russian Journal of Ecology -     

Phenes of Woody Plants: Identification,Scaling, and Use in Population Studies (An Example of Pinus sylvestrisL.)

The methods of identification and scaling of phenes of forest plants are described. The phene identification consists of five stages. Specific features of studies at each stage are shown using identification of the phenes of seed color, cone color, and seed scale structure in Scotch pine (Pinus sylvestrisL.) as examples. The method of phene scaling is based on the comparison of phene frequencies in a bog and in adjacent upland populations of pine. At the boundary between the bog and dry land, the frequencies of population-level phenes change, whereas those of superpopulation-level phenes remain unchanged.     

Analysis of sensitivity of different criteria in cytogenetic monitoring

A sensitivity scale for criteria used in cytogenetic monitoring was constructed on the basis of published data and the results of experiments on exposingZebrina pendula Schirt. plants to radon at various equivalent volume equilibrium activities. It was found that nucleolar activity and suppression of mitotic activity are the most and the least sensitive parameters in terms of response to stress, respectively.     

Cytogenetic Variation in Populations of Scotch Pine

Cytogenetic variation was analyzed in daughter populations of Scotch pine from the Voronezh Forestry. The dependence of the variation on the method of seed collection (the commercial method; the population method, when seeds from a group of phenotypically normal trees in the center of the forest are collected; or the individual method, when seeds from plus trees are collected) and on the ecological situation at the sampling site (ecologically safe conditions or chemical or physical pollution) was studied. The parameters of the mitotic rate and mitotic pathology were estimated at 7–9% and up to 5%, respectively. These parameters may be considered as normal when estimating the quality of seed progeny in pine and when pine is used as a test object in cytogenetic monitoring. The limits of variation and the spectra of cytogenetic characteristics allowing the pine populations to maintain their homeostasis were also determined.     

Effect of Mountain Relief and Industrial Air Pollution on Biometric Characteristics of Pine Stands

The effect of mountain relief and industrial air pollution on biometric parameters of pine stands was studied. The empirical–statistical models of the dependence of biometric characteristics on the parameters of forest sites were developed using raster modeling and multivariate analysis. The possibility of predicting changes in the biometric parameters at any site on the basis of these models is shown.     

Population genetic structure of Pinus tabulaeformis in Shanxi Plateau, China

Chinese pine, Pinus tabulaeformis Carr., a species that ranges broadly across northeastern to southwestern China, plays a vital role in the maintenance of the structure and function of these ecosystems. In this study, we examined the genetic diversity of five widespread populations in Shanxi Plateau, the distribution center of Chinese pine, using 15 random amplified polymorphic DNA (RAPD) primers and five inter simple sequence repeat (ISSR) primers in 140 individual tree samples. Similar genetic differentiation results were obtained from the data of RAPD and ISSR. Based on the two sets of data, Nei’s genetic diversity was 0.2842 and 0.3078 and Shannon’s indices of diversity were 0.4332 and 0.4468. Genetic diversity at the species level was found high relative to that for other genera of Pinaceae. The greatest diversity was observed in the Lingkong Mountain population (0.3860), while the lowest was recorded in the Luya Mountain population (0.3352), most likely as a result of natural adaptation and anthropogenic perturbation. The relative magnitude of differentiation among populations (G _ST) was 0.1491 and 0.1356, respectively, implying that most genetic variation was within the populations (∼0.8509), rather than among populations. Published in Russian in Ekologiya, 2008, No. 1, pp. 36–42. The article was translated by the authors.     

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.     

Cytogenetic Damage of Human Somatic Cells and Weeping Birch Cells in Voronezh Districts with Different Levels of Anthropogenic Pollution

Cytogenetic parameters (the mitotic rate and the frequency of pathological mitoses) of the seed offspring of weeping birch (Betula pendula Roth.) and the frequency of micronuclei in the buccal epithelium of children living in several raions (districts) of the city of Voronezh differing in environmental conditions were studied. Judging from these parameters, the environmental situation was the worst in the Sovetskii raion. A correlation was found between the frequency of pathological mitoses in the roots of birch seedlings and the frequency of micronuclei in the buccal epithelial cells of children. This indicates that the cytogenetic monitoring data obtained in plants may be extrapolated to man.     

Ecological Zoning of Forests in Areas Exposed to Industrial Air Pollution

Morphometric characteristics of the growth of forest stands located at different distances from a large copper-smelting plant were estimated. The set of diagnostic parameters obtained was used for calculating summary parameters of the state (SPSs) of the forest stands and to grade their values for zoning the forests. The results of using semivariance analysis demonstrated the appropriateness of kriging, a method of spatial interpolation, for mapping the surfaces of the state of forests. The map-scheme of the zones differing in the state of forest stands (made on the basis of summary parameters) was compared with the topographic map of the area, which made it possible to estimate the effect of large forms of relief on the location and configuration of the zones.     

Proliferative Activity of Corneal Epithelium and Specific Features of Morphogenesis in Postmetamorphic Rana arvalisNilss. in Urbanized Areas

The mitotic activity and sizes of corneal epithelial cells in postmetamorphic Rana arvaliswere studied in the populations exposed to different degrees of anthropogenic impact in the city of Yekaterinburg. The studies were conducted at the initial stages of frogs' terrestrial life in three consecutive years. Mitotic activity exhibited a slight positive correlation with the liver index, which indirectly reflects the general metabolic rate in young frogs. The combined estimation of proliferative activity, epithelial cell size, and relative liver weight had the highest information value. There was a relationship between the mitotic index and liver index in young frogs from habitats with the highest level of anthropogenic transformation. This indicates that morphogenesis is well-balanced and is likely to decrease the probability of morphological abnormalities in frogs developing in the unstable environment. This physiological property allows the populations to exist and reproduce in urbanized areas.     

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).     

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.     

On adaptations of trees and shrubs in the north of the Russian Far East

Specific ecological features of trees (Chosenia arbutifolia and Betula lanata) and shrubs (Pinus pumila and Duschekia fruticosa) at the northern limit of their distribution are compared. New biomorphological adaptations of these species under extreme conditions are described.     

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.     

Specific features of seedage in Norway spruce (Picea abies karst.) in the northern Moscow region

Climatic characteristics of the northern Moscow region and the periodicity of seedage in Norway spruce were analyzed retrospectively. The relationship between the intensity of seedage and weather conditions in the period before seedage was revealed.     

Comparative Analysis of Ecophysiological Characteristics of Stephanodiscus hantzschii Grun. in the Periods of Its Bloom in Recreational Water Bodies

In the periods of summer and autumn bloom of the Stephanodiscus hantzschii Crun. in recreational water bodies, studies on the vertical distribution of chlorophyll a, its contents per unit biomass, efficiency in using photosynthetically active radiation (E_PhAR), and assimilative activity of microalgae were performed. The results confirmed the existence of two ecophysiological forms of St. hantzschii and provided evidence that both forms are typically autotrophic and can efficiently use low-intensity PhAR for photosynthesis.     

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.     

The Phenomenon of Pseudoviviparity in Alpine and Arctomontane Grasses (DeschampsiaBeauv., FestucaL., and PoaL.)

It is known that pseudoviviparous plant taxa are most numerous in the Arctic and high mountain regions, where they sometimes account for a noticeable part of the local flora and play an important phytocenotic role. The complex of pseudoviviparous taxa is an interesting model for investigating the processes of hybridogenic speciation, as various mechanisms stabilizing the hybrid genetic systems proved to be effective in them. In particular, this concerns vast and taxonomically complex groups such as the genera Deschampsia, Festuca, and Poa.In this paper, published data on the taxonomy, chromosome numbers, and distribution of pseudoviviparous grasses in the Arctic regions and subarctic mountain systems are reviewed.