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1.
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   

2.
Patterns of expansion of geographical ranges of red deer and Siberian roe deer in Yakutia during the 20th century are considered. The area inhabited by red deer in Yakutia has increased almost fourfold over the past 50 years, with an expansion of over 200000 km2 toward the northwest. The geographical range of roe deer in the Lena–Amga interfluve has also changed considerably during the same period. Roe deer sightings in the subarctic zone were reported. The structure of geographical ranges of the species under investigation in different ecological and geographical regions of Yakutia is discussed, and the factors influencing the transformation of geographical range borders are characterized.  相似文献   

3.
The dispersal, population dynamics, and ecological features of the European roe deer at the northern limit of species distribution and also their visits, wintering, and breeding outside the range boundary are discussed. A significant increase in the abundance of roe deer in the northern part of the range and their largescale expansion beyond the historical distribution limit have taken place during the past decade. However, their spread in Karelia and Arkhangelsk oblast is strictly limited, depending primarily on snow depth and duration. Hunting the roe deer as a game species in the region is possible only in the south of Pskov oblast, where habitat conditions are most favorable for it.  相似文献   

4.
Empirical data on the 137Cs activity concentration in meat of roe deer (Capreolus capreolus) roaming in 3 spruce forest areas and one peat bog area are presented and compared. They cover time series of nearly 20 years after a spike contamination in 1986 originating from Chernobyl. A model is presented which considers three soil compartments to describe the change of the availability of 137Cs with time.  相似文献   

5.
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   

6.
The structure of Microtus gregalis colonies was studied in different parts of the species range in Western Siberia, both in the south (Omsk oblast) and in the north (Yamalo-Nenets Autonomous Area), in 1999 and 2000. The colonies studied in the steppe zone of Omsk oblast, southern tundras of the Yamal Peninsula, and mountain tundras on the northern slopes of the Polar Urals prove to have some common structural features. In Omsk oblast, seasonal variation in the area of colonies and the number of entrances to the burrows was revealed, although the general structure of colonies (the pattern of tunnels and location of the nest and storage chambers) was largely the same in spring and autumn.  相似文献   

7.
Environmental conditions in cooling ponds of thermal power plants are favorable for marsh frogs. Their populations inhabiting Verkhne-Tagil and Reftinskoe reservoirs differ in some traits, such as size and age composition, growth rate after metamorphosis, spawning type, fecundity, and characteristics of larval development. Differentiation in body size manifests itself at the early stages of terrestrial life and progresses at later stages. As a consequence, larger individuals may reach maturity and participate in reproduction at an earlier age.  相似文献   

8.
Starting shortly after the Chernobyl accident, samples of roe deer and wild boar from two comparatively highly contaminated Austrian forest stands have been regularly analysed for (137)Cs. Until 1995 average (137)Cs concentrations exceeded 1000 Bq kg(-1) in both roe deer and wild boar. Long-term and seasonal trends are similar in both investigation sites. While (137)Cs aggregated transfer factor (T(ag)) values show a significant decreasing trend in roe deer (ecological half-time 8.6 and 7.2 years, respectively), T(ag)-values in wild boar are highly variable, but rather increasing values are observed over the last years. T(ag)-values for roe deer are between 0.04 and 0.008 m(2)kg(-1) fresh weight (1987-2003); values for wild boar are between 0.008 m(2)kg(-1) (1988) and 0.046 m(2)kg(-1) (1996) fresh weight. Seasonal trends for both species are in good agreement with observations from German forests: increased mushroom ingestion leads to higher (137)Cs T(ag)-values for roe deer in the second half of the year (August-December) compared to the first half (January-July). T(ag)-values for wild boar are highest in the first half of the year.  相似文献   

9.
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.  相似文献   

10.
The results of studies on postfire succession in larch forests of the permafrost zone are discussed. The main directions of successional processes in burned-out areas of different ages are described. It has been shown that secondary pyrogenic successions in larch forests follow the scheme of rapid regeneration without tree species replacement and the model of succession tolerance. Groups of plant species with different life strategies and indicator species characterizing different stages of the overgrowing of burned-out areas have been identified.  相似文献   

11.
A comparative analysis of the spatial-ethological structure of social vole (Microtus socialis Pall.) colonies was made on the basis of studies performed in Dagestan (1987–1991) and the southern Kalmyk Republic (1993–1998). Notwithstanding differences in environmental conditions and the extent and forms of anthropogenic impact, the population structure of the species proved to be similar and stable. Irrespective of population density, its core consists of family groups. Specific features of social behavior (aggressiveness toward unfamiliar animals) provide for the protection of home ranges and help to maintain a stable population structure.  相似文献   

12.
Demographic characteristics of marsh frog (Rana ridibunda Pall.) populations have been studied in cooling reservoirs of Middle Ural thermal power plants, where this species was introduced accidentally. The reservoirs are similar in hydrochemical characteristics but differ in the thermal regime. The populations studied have been found to differ from the reference (natural) populations and from each other in a number of parameters, including the size and age composition of spawners, the type of spawning, and fecundity. Analysis of the results indicates that the observed differences have adaptive significance.  相似文献   

13.
Intrapopulation and interspecific territorial contacts of the eastern Grus leucogeranus population during the breeding period are described and analyzed on the basis of data obtained in the course of long-term observations.  相似文献   

14.
The spatial structure of 10 populations of rare orchid species (Dactylorhiza incarnata, D. traunsteineri, Listera ovata) has been studied in rich fens sporadically occurring in Murmansk oblast. Two levels of plant aggregation within populations have been distinguished: (1) clusters of individuals and (2) isolated population subsets consisting of clusters. General spatial demographic features of orchid populations in the fens are small area (77 m2) and low ecological density (0.009 ind./m2). Characteristics of the population subsets (their number, area, composition, and distance to the neighboring subset) are species-specific and reflect the degree of species rarity in plant communities.  相似文献   

15.
Monitoring of A. uralensis populations in Kamenskii raion, Sverdlovsk oblast, in 1992–2002 and in Kaslinskii raion, Chelyabinsk oblast, in 2000–2001 revealed an increase in the proportion and diversity of minor morphogenetic aberrations and abnormalities in the structure of the cranium along the axis of the Eastern Ural Radioactive Trace (EURT). The samples from the southern and northern parts of the EURT (contaminated with 90Sr to 500 and 4 Ci/km2, respectively) were characterized by directed deviations from the control with respect to the frequencies of phenes of nonmetric cranial traits and an increase in the level of their fluctuating asymmetry in young females, which is indicative of epigenetic rearrangements in populations living in a radioactive environment.  相似文献   

16.
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   

17.
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   

18.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season has shifted to earlier dates by the end of the 20th century.  相似文献   

19.
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   

20.
The spatiotemporal structure of the muskrat population has been studied by means of the prenatal radioactive marking of juveniles with 45 Ca and their subsequent recapture in the test area. The muskrat population is characterized by a cyclic type of spatial structure, with seasonal transition from a mosaic type of settling to a diffuse type and, after the breeding season, vice versa.  相似文献   

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