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1.
The patterns of spatial variation in gastropod diversity in the waterbodies of western Siberia have been revealed. The highest species and generic diversity of freshwater gastropods is found in the waterbodies of the forest-steppe zone; from there, these parameters significantly decrease northwards, reaching their minimum beyond the polar circle. The proportion of gastropods of non-European origin increases in the same direction. The possible reasons for these changes in the spatial diversity of aquatic gastropods and the likely connections between the latitudinal variation of their diversity and the geological history and features of the relief of western Siberia are discussed. It is assumed that the forest-steppe zone of western Siberia is a local center of aquatic gastropod diversity.  相似文献   

2.
Species diversity of the genus Kephyrion Pascher in the basin of the Sabun River (subzone of northern taiga in western Siberia) is discussed. Its territory holds the Sibirskie Uvaly Nature Park. The genus Kephyrion is represented by 16 specimens in the basin of the Sabun River and by 14 specimens in the bodies of water of the park. Their temperature, visibility, and active reaction of water stimulating vegetation have been identified. Five species and one variety of the genus have been for the first time registered in the flora of western Siberia.  相似文献   

3.
The vegetation cover in the north of Central Siberia has been assessed from lichenological data. The approaches and methods of lichen-based indication of the state of vegetation cover have been developed with the application of the data on diversity of lichens and lichen synusias, their projective cover and morphological deviations. The species of lichens and synusias that can be used for indication purposes have been defined. The changes in the characteristics of the lichen component in vegetation cover under the increasing chemical air pollution caused by industrial plants have been examined. The early deviations are indicated by morphological changes of lichen thalli, species depletion, and diversity of lichen synusias. Practical recommendations on lichen indication of the vegetation cover in the north of Siberia have been given.  相似文献   

4.
In recent decades, the relationships between environmental conditions and community structures of stream macroinvertebrates have been investigated in many parts of the world. However, knowledge about assemblages of mayflies and other stream macroinvertebrates in Siberia (northern Asia) and Asia is limited. In fact, the patterns in mayfly species richness and assemblage structure in relation to environmental parameters have not been previously examined in western Siberia. The aim of the present study was to examine the relationship between Ephemeroptera community structure and physical parameters along a river altitude/longitude gradient in Siberia. The results showed that maximum species richness was at relatively low altitudes, high water temperatures, slow current velocities, medium stream widths, medium‐small substrate particle size, and the presence of macrophytes. The mayfly assemblage was separated using TWINSPAN classification into eight distinct groups, which differed significantly with respect to at least one measured environmental factor. Multivariate ordination (detrended correspondence analysis) revealed that mayfly assemblages are structured by a single dominant gradient of altitude‐related environmental variables; altitude and water temperature were the best predictors. Ordination further revealed that mayfly assemblages are structured by altitude‐related environmental factors at high elevations, whereas in the lowlands these factors are less important.  相似文献   

5.
An automated conjugate classification of forest growing conditions and forest vegetation has been developed based on the example of the southern part of Yenisei Siberia; maps of potential forest growing conditions and forest-cover regeneration dynamics have been constructed on the basis of the automated recognition of remote sensing data and a system of conjugate analysis of dissimilar data in GIS. The proposed approach makes it possible to promptly create and update forest cover maps, which is particularly important for the vast taiga regions of Siberia.  相似文献   

6.
Currently there is a complicated situation in the taxonomy of widespread species such as birch (Betula L.). A large number of species of this genus in Siberia and the Russian Far East has been described, but one encounters an insurmountable obstacle when trying to carry out a more detailed study: the impossibility of finding them for a second time in nature or at least collect plants that have identical characteristics to the typical examples of the described species. All of these species are characterized by a very high variability of traits. These are the traits of Betula pendula and B. microphylla in the southern parts of Central Siberia and Betula pendula (= B. platyphylla) and B. lanata in Eastern Siberia and in the northern regions of the Russian Far East. This suggests intense and widespread hybridization between these species. In connection with this, research of this genus throughout North Asia has begun. These studies have been carried out over 40 years. To date, many works in periodicals and several monographs have been published using the data of numerous expeditions. This paper shows the role of natural hybridization in plant taxonomy using the example of the Siberian species of birch. It is necessary to have a clear understanding of the hybridization processes on large areas that include the ranges of contact species. Solving problems of taxonomy only by studying small local populations is a hopeless pursuit.  相似文献   

7.
Changes in the composition of wood organic matter in dead-standing spruce and larch trees depending on the period after their death have been studied in the north of Central Siberia. The period after tree death has been estimated by means of cross-dating. The results show that changes in the composition of wood organic matter in 63% of cases are contingent on tree species. Wood decomposition in dead-standing trees is accompanied by an increase in the contents of alkali-soluble organic compounds. Lignin oxidation in larch begins approximately 80 years after tree death, whereas its transformation in spruce begins not earlier than after 100 years. In the forest-tundra of Central Siberia, the rate of wood organic matter transformation in dead-standing trees is one to two orders of magnitude lower than in fallen wood, which accounts for their role as a long-term store of carbon and mineral elements in these ecosystems.  相似文献   

8.
As a result of a phytopathological investigation into birch (Betula pendula) stands in the Krasnoyarsk group of areas (south of Middle Siberia), newly appearing and existing nidi of bacterial dropsy have been discovered. The influence of growth conditions on morbid affection in birch forests and the correlation between disease prevalence and characteristics of forest inventory have been established. The specificities of tree affection within phytocenoses and the influence of disease on the sanitary state of birch forests have been discussed.  相似文献   

9.
10.
Iurkov AM 《Mikrobiologiia》2005,74(4):533-536
Two ascomycetous yeast strains have been isolated near Novosibirsk from oak exudate. The strains have been identified as Saccharomyces paradoxus Bachinskaya based on the results of biochemical tests. The conspecificity of the isolates with S. paradoxus was confirmed by electrophoretic karyotyping and restriction analysis of the ITS region of its rDNA. This first isolation of S. paradoxus in Siberia provides evidence for the continuity of its natural habitats.  相似文献   

11.
Autosomal gene pools of 27 populations representing 12 ethnic groups of Siberia, Central Asia, and the Far East have been characterized for the first time using a set of eight polymorphic Alu insertions. The results of our analysis indicate a significant level of genetic diversity in populations of northern Eurasian and the considerable differentiation of their gene pool. It was shown that the frequency of the Alu (?) allele at the CD4 locus was inversely related to the magnitude of the Mongoloid component of the gene pool: the lowest and highest frequencies of the CD4 Alu deletion were recorded in Eskimos (0.012) and in Russians and Ukrainians (0.35), respectively. A gene flow analysis showed that Caucasoid populations (Russians, Tajiks, and Uzbeks), as well as Turkic ethnic groups of southern Siberia (Altaians and Tuvans), Khanty, and Mansi populations, in contrast to ethnic groups of eastern Siberia and the Far East, have been recipients of a considerable gene flow. A correlation analysis showed that genetic distances determined using polymorphic Alu insertions were correlated with the anthropological characteristics of the populations studied.  相似文献   

12.
The structures of earthworm communities and their distribution in the southern ecosystems of Middle Siberia have been studied at the local (biogenocenotic), topological (facial), and regional landscape levels. Long-term observation data at fixed sites have been used to construct map charts that portray the landscape-ecological patterns for variations in the quantitative characteristics and species compositions of lumbricides, which depend on abiotic factors and the anthropogenic impact.  相似文献   

13.
The paper presents data on the composition and distribution of freshwater sponges in western Siberia. Recently, four species have been found in lakes and rivers, and one species has been recorded in a study of palynological and archaeological samples. Freshwater sponges live mainly in the small rivers and lakes of the forest-steppe and southern taiga zones. About a hundred taxa of aquatic invertebrates have been recorded together with the found sponges. The biomass of sponges among the zooperiphyton significantly decreases northwards.  相似文献   

14.
Natural environments of the taiga zone in central West Siberia have been analyzed, with emphasis placed on the geological and morphological structure of the territory and morphology of soils. The main factors of soil formation are recognized, the main processes of soil formation are revealed, and a systematic list of soil kinds is compiled.  相似文献   

15.
The concentrations of carotenoids buried in the bottom sediments of Lake Shira (Siberia, Khakassiya) have analyzed for the period of the last 2300 years. The bottom sediments were found to contain carotenoids, which are molecular markers of the corresponding groups of Phototrophic organisms. The bottom sediments of Lake Shira were shown to be a promising object for climate reconstructions of the Late Holocene in southern Siberia.  相似文献   

16.
The population of testate amoebae from the most typical middle taiga bogs of Western Siberia have been studied. More than one hundred (103) species and intraspecific taxons of testate amoebae have been revealed in recent surface samples. The relation between ecological characteristics of habitats and the composition of a Protozoa population has been demonstrated. The ecological preferences of species concerning the index of wetness, ash level, and acidity have been revealed. Using the correspondence analysis, the ecological optimums and the tolerance of species and intraspecific taxons of testate amoebae have been established.  相似文献   

17.
In previous studies, 13 different recessive embryonic lethal genes have been associated with t haplotypes in the wild mice of the species Mus domesticus. In this communication we have analyzed five populations of Mus musculus for the presence and identity of t haplotypes. The populations occupy geographically distant regions in the Soviet Union: Altai Mountains, western and eastern Siberia, Azerbaijan and Turkmenistan. No t haplotypes were found in mice from eastern Siberia. In the remaining four populations, t haplotypes occurred with frequencies ranging from 0.07 to 0.21. All the t haplotypes extracted from these populations and analyzed by the genetic complementation test were shown to carry the same lethal gene tcl-w73. In one population (that of western Siberia), another lethal gene (tcl-w5) was found to be present on the same chromosome as tcl-w73. This situation is in striking contrast to that found in the populations of the western form of the house mouse, M. domesticus. In the latter species, tcl-w73 has not been found at all and the different populations are characterized by the presence of several different lethal genes. The low diversity of t haplotypes in M. musculus is consistent with lower genetic variability of other traits and indicates a different origin and speciation mode compared to M. domesticus. Serological typing for H-2 antigenic determinants suggests that most, if not all, of the newly described t haplotypes might have arisen by recombination of tw73 from M. musculus with t haplotypes from M. domesticus either in the hybrid zone between the two species or in regions where the two species mixed accidentally.  相似文献   

18.
The data on the qualitative and quantitative composition of zooperiphyton from seven large rivers of Western Siberia are presented. The species similarity of zooperiphyton has been documented in most of the rivers. The biomass in unpolluted parts is mainly formed by the larvae of caddis flies. Factors which effect the composition and structure of zooperiphyton have been determined. Changes in the structure and quantitative development of zooperiphyton are shown.  相似文献   

19.
Polymorphism for E2 locus of human serum cholinesterase was studied in populations of evenks and yakuts of Krasnoyarsky region by the method of starch gel electrophoresis. Thee frequencies of C5+ phenotype correspond to C5+ frequencies in other mongoloid populations of Siberia. The activity of cholinesterase was determined by semiquantitative technique. Three individuals with a sharply decreased cholinesterase activity have been revealed.  相似文献   

20.
Macroentomology analysis mainly studies terrestrial insect species with a hard exoskeleton (Coleoptera, some Hymenoptera, Homoptera, and sometimes other orders). The method has shown a great potential for environmental and climatic paleoreconstructions of the Quaternary worldwide. A large volume of the entomological material has also been collected in Siberia. However, an analysis of the published data demonstrates that the investigations of fossil insects are irregular in Siberia. The most studied sites are in Northwestern and Central Siberia and in northeastern Russia. The rest of Siberia is still almost unstudied. This work aims to present this method (sampling method, laboratory treatment, and examples of paleoreconstructions) to a wide group of researches. In some cases, the study of insects allows one to make more accurate reconstructions than traditional paleobotanical methods. The application of this method is effective for recognizing differences in herbaceous communities similar in appearance, which were typical for the cold periods in the Pleistocene.  相似文献   

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