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1.
The structures and differentiation patterns of the Norway spruce (Picea abies) and Siberian spruce (P. obovata) populations have been studied in a wide area, including the transition zone of their continuous geographic range. The areas occupied by transitional populations have been detected. Series of distinct populations of the Norway and Siberian spruces are located to the west and east of them, respectively.  相似文献   

2.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples, the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the Kalinin NPP has no effect on wild populations of predatory mammals.  相似文献   

3.
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   

4.
The effect of long-term exposure to a stress factor on the pattern of variation and intrapopulation differentiation with respect to phenotypic plasticity was studied in Crepis tectorum L. by means of family analysis of various traits in seedlings. Trends in the changes of variation patterns in populations and the possible consequences of the decrease in the proportions of genotypes determining a low sensitivity to environmental changes and in genotypic diversity with respect to phenotypic plasticity are discussed.  相似文献   

5.
Groups of spruce populations growing in western and southwestern, central, and northern regions of the Komi Republic significantly differ from each other. Trees with a phenotype intermediate between Norway (Picea abies) and Siberian (P. obovata) spruce prevail in the first group, their proportion in the second group does not exceed 20%, and almost all trees in the third group have the Siberian spruce phenotype.  相似文献   

6.
The population structure of the Colorado potato beetle in the Southern Urals is discussed. This population is shown to be divided into two groups of local populations, in central and in peripheral parts of the study area, which differ in degree of intrapopulation diversity. The founder effect and insecticide pressure are regarded as probable factors that have contributed to this division.  相似文献   

7.
The patterns of molt in the chiffchaffs of the nominotypical subspecies from central Europe and eastern European subspecies from the Ladoga region are compared with that of the Siberian subspecies from the lower Ob region. The onset dates of postjuvenile molt in the Siberian subspecies are controlled endogenously, while in the nominative and, probably, eastern European subspecies they are under photoperiodic control. The molt of chiffchaffs from central Europe is no less complete than in birds from the Ladoga region and more complete than in Siberian birds. The individual duration of molt is the shortest in Siberian birds and the longest in central European birds, being intermediate in birds from the Ladoga region. Differences in the pattern of postnuptial molt between chiffchaffs from the Ladoga and Ob regions concern its duration and completeness. The completeness of molt proved to be reduced in half of examined birds from the Ladoga region and in some birds from the Ob region. The duration of complete molt in birds from the Ob region is smaller (40 days vs. 60 days in birds from the Ladoga region) at a longer daylight period, which is evidence for a higher rate of feather growth. The completeness and timing of prenuptial molt do not differ between the subspecies.  相似文献   

8.
Analysis of geographic variation of chloroplast DNA in the eastern European and western Siberian (Tobol) groups of Calluna vulgaris populations isolated from each other for a long period of time has revealed distinct differentiation between them. It has been shown that three populations growing in the Russian Plain and Karelia share two haplotypes characteristic of central Europe, while three Tobol populations contain one haplotype F occurring in Sweden. These results confirm the hypothesis of genetic divergence between the Tobol and eastern European groups of C. vulgaris populations.  相似文献   

9.
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   

10.
The impact of the nuclear polyhedrosis virus on the population dynamics of the gypsy moth Lymantria dispar L. has been studied. The results have shown that polyhedrosis morbidity in the western Siberian population of the insect is relatively low, compared to that reported for North American and European populations. A possible cause of this situation is found in the high migration activity of moths in the Asian L. dispar populations, which allows the virus load on the biotope to remain relatively stable and insufficient for the initiation of mass viral diseases during population outbreaks.__________Translated from Ekologiya, No. 3, 2005, pp. 222–226.Original Russian Text Copyright © 2005 by Ilinykh.  相似文献   

11.
Many studies have identified climate warming to be among the most important threats to biodiversity. Climate change is expected to have stronger effects on species with low genetic diversity, ectothermic physiology, small ranges, low effective populations sizes, specific habitat requirements and limited dispersal capabilities. Despite an ever-increasing number of studies reporting climate change-induced range shifts, few of these have incorporated species’ specific dispersal constraints into their models. Moreover, the impacts of climate change on genetic variation within populations and species have rarely been assessed, while this is a promising direction for future research. Here we explore the effects of climate change on the potential distribution and genetic variation of the endemic Pyrenean newt Calotriton asper over the period 2020–2080. We use species distribution modelling in combination with high-resolution gridded climate data while subsequently applying four different dispersal scenarios. We furthermore use published data on genetic variation of both mtDNA and AFLP loci to test whether populations with high genetic diversity (nucleotide diversity and expected heterozygosity) or evolutionary history (unique haplotypes and K clusters) have an increased extinction risk from climate change. The present study indicates that climate change drastically reduces the potential distribution range of C. asper and reveals dispersal possibilities to be minimal under the most realistic dispersal scenarios. Despite the major loss in suitable climate, the models highlight relatively large stable areas throughout the species core distribution area indicating persistence of populations over time. The results, however, show a major loss of genetic diversity and evolutionary history. This highlights the importance of accounting for intraspecific genetic variation in climate change impact studies. Likewise, the integration of species’ specific dispersal constraints into projections of species distribution models is an important step to fully explore the effects of climate change on species potential distributions.  相似文献   

12.
Species composition, community structure, and seasonal population dynamics of carabids in spring wheat fields were studied in the vicinity of Yekaterinburg. In addition, the effects of crop treatment with the pyrethroid insecticide Decis on carabid populations was analyzed. The results showed that the numbers, species diversity, and the prevalence of certain trophic groups of carabids changed during the season. After the treatment of small areas with Decis, the number of carabids in catches decreased for a short period of time. During the second and third weeks after the treatment, the numbers of carabids increased above the control level. The structural rearrangement of the carabid community was observed in the areas treated with the insecticide.  相似文献   

13.
Molecular genetic methods (AFLP and ITS1–5.8S–ITS2 rDNA analysis) have been used to study the level and structure of genetic diversity in relict populations of the Ural endemic Gypsophila uralensis Less. in the northeast of European Russia. Intraspecific genetic differentiation is most clearly manifested between G. uralensis Less. subsp. pinegensis (Perf.) Kamelin locally endemic to the north of Europe (Arkhangelsk oblast, locus classicus) the population of G. uralensis Less. subsp. uralensis on limestone outcrops along the Shchugor River, the Subpolar Urals. The cluster of Timan populations (on limestone outcrops along the Svetlaya, Pizhma, and Myla rivers) is autonomous and genetically heterogeneous. Genetic distances between model G. uralensis s.l. populations are correlated with geographic distances. The size and abundance of relict populations show a descending gradient in the forest zone, and parameters of their genetic diversity [1] and unbiased expected heterozygosity have been found to decrease along this gradient.  相似文献   

14.
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.  相似文献   

15.
Modern data on the diversity of morphology and morphogenesis of gametophytes in homosporous ferns, their vegetative reproduction, and the existence of their colonies growing separately, independently of sporophytes, are reviewed. The ontogenetic states of gametophytes are identified and characterized. The problem of gametophyte chemical interactions mediated by antheridiogen, an exohormone, is discussed. These intrapopulation interactions determine the polyvariant character of gametophyte ontogeny and the complex age and sex structure of their colonies.  相似文献   

16.
Field and laboratory investigations were performed to study the distribution and functional significance of antilysozyme activity (ALA) in algal cultures. According to the results obtained, ALA as a trait is widespread among green and blue-green algae but is expressed to different extents. Experiments on the algae–zooplankters model showed that ALA is a factor facilitating the survival of algae in freshwater communities by promoting the establishment of their trophic and symbiotic relationships with other aquatic organisms. Analyzing the intrapopulation structure of algal cultures associated with zooplankters, it was shown that changes in the ALA of algal clones have adaptive significance, providing for a greater stability of algal populations in biocenoses.  相似文献   

17.
A statistical analysis of interannual variation in a set of vegetative and generative characters over 13 years has been performed to characterize the growth and seed production dynamics of the Siberian stone pine (Pinus sibirica Du Tour) in the southeast of the forest zone in western Siberia. The results have shown that the range of fluctuations in most of vegetative characters is ordinary and their distribution is close to normal. The range of fluctuations in many generative characters is enormous (from 0 to +∞), and the distribution of their values is usually skewed, with low values being recorded several times more frequently than high values. Most variable are the proportion of abortive cones and other characters that are determined mainly in the spring of the pollination year. These characters account for a very high level of variation in the total seed production.  相似文献   

18.
Adaptive strategies of cyclomorphic rodent populations (Rodentia) under extreme conditions of droughts (in 1975 and 2010) have been analyzed on the basis of functional–ontogenetic approach. The following features of these strategies have been revealed: minimization of metabolic processes, block of sexual maturation, intergenerational crossing, prolongation of breeding period, and species-specific features in the dynamics of intrapopulation processes. Profound changes in the level of long-term oscillations of abundance after the drought have been noted in different species. Evidence is provided for the possibility of extremely rapid population rearrangements on an evolutionary scale that are fixed in a series of generations.  相似文献   

19.
The distribution of nine chloroplast DNA haplotypes in four insular North-Atlantic and four European coastal Atlantic populations of Calluna vulgaris in the glacial zone of the range has been analyzed in comparison with that in six marginal southern populations in the nonglacial zone of the Atlantic and Mediterranean regions. As a result, two hypothetical Pleistocene refugia (HPRs) for this C. vulgaris population group have been revealed, one in the Cévennes mountain range and the other in the Southern Alps (Trento). Judging from the 1–FST value, it has been found that the group of populations in the glacial Atlantic zone and adjacent European coastal Atlantic region is genetically similar to the HPR in the Cévennes at a highly significant level (p ≥ 0.999) and less similar to the HPR in Trento; however, it differs significantly from other Mediterranean and Atlantic populations. It has been concluded that the most probable hypothetical Pleistocene refugium for the recent C. vulgaris populations of the northeastern Atlantic and European coastal Atlantic regions was in the west of the Mediterranean, in the Cévennes, while the additional refugium was in the Southern Alps. Possible directions of the postglacial dispersal and recolonization of habitats by C. vulgaris populations from the western Mediterranean to the northeast of the Atlantic and to Scandinavia have been revealed.  相似文献   

20.
Aftereffects of exposure to long-term chemical pollution with fluorine and sulfur compounds on intrapopulation differentiation of the rates of growth and development has been studied on Crepis tectorum L. progenies obtained from seeds collected in a pollution gradient and grown in a greenhouse under uniform ecological conditions. The results have shown that long-term stress (exposure to toxic gaseous pollutants) leads to significant changes in the intrapopulation structure, which are manifested in an increase in the proportion of plants with a low rate of development, a low relative rate of the linear growth of metameres (leaves), but a higher relative rate of their formation.__________Translated from Ekologiya, No. 4, 2005, pp. 243–251.Original Russian Text Copyright © 2005 by Trubina.  相似文献   

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