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1.
The results of a karyological study on Siberian stone pines growing in the bog demonstrated differences from the populations of this species studied earlier with respect to sizes of chromosomes and location of secondary constrictions. The number of nucleolar organizer regions in the chromosomes of Siberian stone pine trees growing in the bog was larger than in other populations. A wide spectrum of chromosome aberrations was revealed, which had not been observed in this species before. These were genome and chromosome aberrations of various types, as well as structural aberrations accompanied by changes in the number of chromosomes. It is assumed that the aberrations in the karyotype of Siberian stone pine resulted from stressful conditions.  相似文献   

2.
The results of identification and dating of frost, false, and light rings in the wood of living and dead Siberian juniper plants growing at the upper forest boundary in the Polar Urals were used to determine the incidence of these structures over the past 630 years. Based on the data of instrumental observations on daily air temperature, the dates and rates of temperature decrease in the years of pathological tree ring formation were analyzed. The recurrence and intensity of extreme temperature drops during the growing seasons of the past six centuries were reconstructed. The severest frosts occurred in the summer seasons of 1601, 1783, 1857, 1882, and 1968.  相似文献   

3.
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.  相似文献   

4.
The dynamics of the sex and age structure of Siberian roe deer in central Yakutia has been analyzed over the period from 1998 to 2011. In the snowy winter of 2004, mass migration and high mortality of the animals were recorded. The following shift of the adult sex ratio in favor of females and increase in the proportion of calves provided for rapid population recovery. Climate warming, accompanied by increase in the amount of snow, has impaired living conditions for Siberian roe deer. Realization of the species reproductive potential is restrained by natural and anthropogenic elimination factors, and prospects for future population growth are poor.  相似文献   

5.
Daily food requirements and seasonal aspects of the diet have been studied in the Siberian roe deer (Capreolus pygargus Pall.) at the northernmost limits of its range in northeastern Asia, under specific sharply continental climatic conditions of the East Siberian light conifer (larch) taiga forests. Seasonal changes in the composition of the diet and the consumption of different food items are discussed.  相似文献   

6.
Regional Environmental Change - Increased dieback and mortality of “dark needle conifer” (DNC) stands (composed of fir (Abies sibirica), Siberian pine (Pinus sibirica) and spruce (Picea...  相似文献   

7.
Structure and diversity of populations in the European and Siberian spruces were studied by their phenotypes. On vast areas of their total range in the east of Europe and Siberia, significant variability of intrapopulation diversity index in the frequency of individual phenotypes is observed. All analyzed populations are divided into two large groups: with low (and decreased) and high (and increased) levels of intrapopulation diversity. A high level of diversity was observed in the regions with hybrid or intermediate populations, while a low level was in the regions with populations of European and Siberian spruces without genetic interference. Mean level of diversity is typical for the areas with populations transient in these characters.  相似文献   

8.
Mitochondrial DNA (mtDNA) variation has been studied in populations of the Siberian larch with the use of five PCR-based markers characterizing 29 haplotypes. The studied populations from the main parts of the Siberian larch range belong to several geographically isolated groups with their specific sets of haplotypes, which have probably originated from separate refugia for forest vegetation of the last glacial maximum. Conclusions concerning the possible location of these refugia and the ways and pattern of the postglacial recolonization of the recent Siberian larch range are drawn. The spatial distribution of haplotypes within individual populations is nonrandom. The typical size of the area occupied by a group of plants with the same haplotype is 50–100 m across.  相似文献   

9.
A comparison of two Siberian moth populations from the Altai Republic (feeding on Siberian fir) and the Tyva Republic (feeding on Siberian larch) has revealed no differences between them with respect to ecophysiological parameters of larval growth and feeding on needles of the same conifer species under laboratory conditions. The index of appropriateness of food plants for the larvae from both populations decreases in the series larch > fir > spruce > pine. The age-related dynamics of parameters characterizing the feeding and growth of larvae are independent of the population to which the insects belong.  相似文献   

10.
A transient population outbreak of the Siberian larch casebearer, Coleophora sibiricella Flkv. (Lepidoptera, Coleophoridae), in a protective forest strip and its consequences for the host tree species (Larix sibirica Ledeb.) have been studied for the first time. It has been shown that one-time complete defoliation by this pest and the following infestation by xylophagous insects result in tree death, while the productivity of surviving trees decreases significantly. The results of this study indicate that the Siberian larch casebearer is a major phyllophagous pest of larch and that its populations must be monitored by specialists in forest pathology.  相似文献   

11.
The data presented have been obtained in the course of long-term stationary quantitative studies on the annual seed reproduction dynamics of Siberian stone pine (Pinus sibirica Du Tour) stands, including the abundance of seedlings, and the local population of the nutcracker (Nucifraga caryocatactes macrorhynchos C.L. Brehm) in forests of the Northern Urals. Statistically significant consortive relationships of the nutcracker population density with the yield of Siberian stone pine seeds and of the abundance of pine seedlings with the yield of seeds and the abundance of nutcrackers over preceding years have been hrevealed for the first time and formalized mathematically.  相似文献   

12.
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.  相似文献   

13.
Changes in the anatomical characters of ectomycorrhiza in Siberian fir and Siberian spruce were studied in natural forests polluted with heavy metals (Cu, Zn, Cd, Pb, As, and Fe) and sulfur dioxide. As technogenic load increased, the total radius of mycorhiza terminals and plant roots included in them increased in the organic horizon and decreased in the mineral part of the soil. The absolute thickness of fungal mycorhiza caps and their relative contribution to the total volume of consuming organs increased under pollution. The observed responses were regarded as adaptive, aimed at compensating the adverse effects caused by technogenic pollution.  相似文献   

14.
Regional Environmental Change - This study analyses dynamics of the hydrological regime of Bele-Shira closed basin and evaluates the potential for using radial growth of Siberian larch (Larix...  相似文献   

15.
In the southern-taiga low grass–green moss fir forest completely defoliated by the Siberian moth, the rate of soil respiration in the third year after the pest population outbreak was 1.5 times higher than in an undisturbed tree stand. This was explained by a significant increase in the abundance and activity of soil microorganisms in the pest-defoliated forest, which occurred due to the qualitative changes in the litter composition and the increased temperature and moisture in the upper soil layers. The rate of carbon emission from the soil in the defoliated forest was 41.7 kg/ha per day, compared to 28.3 kg/ha per day in the undisturbed fir forest.  相似文献   

16.
Reference populations identified within the continuous range of Norway (Picea abies) and Siberian (P. obovata) spuces significantly differ in biometric characters of seed scales, relative position in the same coordinate system (Root 1 and Root 2), phenotypic structure, and mutual taxonomic position (according to the squared Mahalanobis distance). Due to the symmetrically equal positions of the populations relative to each other, they can be used as reference populations in discriminant analysis at a two-, three- or five-class gradation of the test character.  相似文献   

17.
The role of the Siberian musk deer in the diets of the Amur tiger, brown bear, and Asian black bear has been studied in the Sikhote-Alin State Biosphere Reserve in 1992 to 2016. Information has been collected from 763 tiger feeding sites, and the contents of tiger feces have been analyzed. Radiotelemetry has been used to evaluate tiger–musk deer relationships. The musk deer accounted for 0.26% of all animal species found to be eaten by the tiger. Musk deer remains in feces of the tiger, brown bear, and Asian black bear occurred with frequencies of 1.3, 0.2, and 0.3%, respectively. A case of musk deer avoiding the presence of brown bear is described.  相似文献   

18.
The natural microflora of Middle Siberian karst cavities, which comprises psychrotolerant bacteria and fungi capable of growing at 3–15 and 3...+28°C, respectively, has been studied. Bacteria are ubiquitous in caves, their count varying from 103 to 107 cells/g ground. The bacteria have been identified as Pseudomonas, Arthrobacter, Bacillus, and coryneform bacteria. Fungi have been found in places exposed to increased anthropogenic impact, their count being as large as 106 to 107 cells/g ground. Mucor, Penicillium, and Chrysosporium were dominant fungal genera.  相似文献   

19.
Phenotypic variation in the widespread Siberian and Mongolian butterfly species Coenonympha amaryllis (Stoll, 1782), an indicator of undisturbed steppe communities, is analyzed. It is shown that its size variation is influenced by a complex of climatic factors, the most important of them being the average starting date of the frost-free period and average annual temperature in the region. Longitude-dependent variation in size is described by a “sawtooth curve” characteristic of species with changing voltinism.  相似文献   

20.
The structure of the crown and branching; the growth, development, and ontogeny of branches; and organogenesis and growth of female shoots in the model Siberian stone pine trees were studied in four types of habitats at the timberline in the central Altai Mountains (1700–2170 m a.s.l.). The results provided evidence that the ecological forms of trees appear due to changes in the pattern of branching as well as to the decreased rate of vegetative (primarily apical) growth. The diameter of the shoot pith is one of the most variable characters reflecting the deterioration of environmental conditions at higher elevations.  相似文献   

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