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1.
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   

2.
Long-term studies (1975–1999) and large amounts of field data (collections and observations on marked animals) have been used to analyze the growth and development of the northern mole vole (Ellobius talpinus Pall., 1770). Data are presented on the postnatal development and life spans of particular age groups of this species and on the dynamics of growth and life spans in the resident and migrant parts of the population. It is shown that the population is divided into slowly growing and rapidly growing groups, which is related to population dynamics. The timing of sexual maturation of the northern mole vole depending on the time of birth is clarified. It is shown that stable reproduction of this underground species is accounted for by the presence of seasonal generations.  相似文献   

3.
In seven higher plant species of different taxa, structural features of underground organs have been considered, and the levels of intraspecific variation in some characters of these organs have been determined. Different pathways of the structural adaptation of these species to the environment are demonstrated on the morphological and anatomical levels.Translated from Ekologiya, No. 2, 2005, pp. 97–105.Original Russian Text Copyright © 2005 by Tarshis.  相似文献   

4.
Ecological conditions for the Altai snowcock and the history of formation of its range in the Altai-Sayan mountain region are discussed. The range of this species extends mainly over mountain massifs surrounding the Great Lakes Basin in western Mongolia and the Tuva Basin. These regions are characterized by broken relief with steep slopes. Snowcocks populate both humid high-mountain areas of the Alpine type and dry-steppe areas in middle and low mountains. Expansion of this species to the Altai-Sayan region is attributed to Miocene-Pliocene aridization well manifested in central Asia. The recent distribution of the Altai snowcock over different altitudinal belts is explained by alternation of glaciations and interglacial periods in the Pleistocene and anthropogenic impact in the Holocene. The total abundance of this rare species is estimated at 10000–12000 individuals.  相似文献   

5.
Following the Chernobyl accident, 137Cs contamination levels of wild boar in some districts of Southern Germany are still exceeding thousands of Bq kg−1. While the long term 137Cs concentration in forest plants, mushrooms, and roe deer meat has decreased significantly, for wild boar it has remained constant during the last decade. Between 1998 and 2008, we analysed the muscle meat of 656 wild boars shot in the district (“Landkreis”) Ravensburg. The 137Cs activity concentration showed considerable variability from less than 5 up to 8266 Bq kg−1 and it followed a seasonal pattern, which is attributed to changes in dietary habits, fodder availability, meteorological conditions and specific behaviour of 137Cs in wild boar organism. Tag values for wild boars from the district Ravensburg varied from 0.008 to 0.062 m2 kg−1 during 2000–2008.  相似文献   

6.
Annual cycle phenomena taking place in the nesting part of the range, such as dates of migration and breeding and molting pattern, have been studied in the wood warbler in northwestern Russia, at the boundary of its nesting range. The results provide evidence that the annual cycle of long-distance migrant birds living at the boundary of their nesting range has certain specific features.  相似文献   

7.
The results of studies on transformations of the floristic diversity of forest ecosystems under the effect of human activity in the southern and middle taiga subzones of the Komi Republic are reviewed. It is shown that the change of dominants in the tree layer leads to the formation of specific biotopes and, as a consequence, to changes in floristic complexes and the cenotic roles of species in the lower layers of forest communities. In the study region, the -diversity of forest communities is determined mainly by two environmental factors: soil fertility and acidity. The factor of illumination has only a slight effect on the -diversity of taiga forests, which is especially clear in the group of deciduous forest formations.__________Translated from Ekologiya, No. 3, 2005, pp. 180–185.Original Russian Text Copyright © 2005 by Degteva.  相似文献   

8.
Land cover changes induced by historical cultivation in ecologically fragile areas involving important issues such as environmental change, ecology, and human sustainability are particularly worthy of attention. This paper reconstructs the spatial distribution of cultivated areas at the county level in the eastern farming-pastoral ecotone of northern China for four time periods during the twentieth century. The paper also analyzes how the location of cultivation ratio contours of 15 and 30 %, representing the boundaries of agricultural areas, have moved and the formation process of farming-pastoral ecotone patterns during this period. The study concludes that the area and ratio of cultivated land fluctuations increased during the twentieth century. The boundaries of the cultivation ratio contours of 15 and 30 % continually moved west and north. Moving north took priority over the other directions during the period of 1916–1940, when its center moved the farthest during the twentieth century, and the boundaries primarily moved westward during 1940–1980 and northwestward during 1980–2000. The distance, direction, and extent of the movement of the cultivation boundaries are all related to agricultural area expansion processes during this period, finally resulting in the creation of the modern farming-pastoral ecotone pattern.  相似文献   

9.
The spatial distribution of ichthyofauna in water bodies of the northern Polar Urals is reviewed. Four lake types are distinguished according to the species composition of fishes. The faunistic ranking of water bodies has been performed. The zoogeographic boundary between the ranges of the European and Siberian ichthyofaunas in the freshwater part of the Arctic has been determined.  相似文献   

10.
Conflicts between human demands for clean water and terrestrial ecosystems’ needs for water are increasing. Such conflicts are stronger in the case of groundwater, as one of the cleanest forms of drinking water, and are expected to increase in frequency, in the context of population growth and climatic changes. This paper argues that behavioral approaches are essential not only toward understanding how socio-ecological conflicts emerge, but also how they could be overcome. A theoretical the framework is proposed, which suggests that the behaviors/actions of actors who sustain such conflicts can be understood by examining their ‘boundary judgments’ regarding natural resources and sustainability, in interaction with their powers/resources to implement the preferred behaviors. The concept of boundary judgements is rarely used in investigating sustainability conflicts. This concept is operationalized in relation to nature-society conflicts and applied empirically to illuminate the conflict in a case study from the Netherlands. Further, the theoretical framework suggests a parsimonious, yet comprehensive, typology of mechanisms that can be used to change/‘converge’ the behaviors and actions of the actors contributing to the problem, toward conflict closure. These are referred to as convergence mechanisms and can be persuasive, enabling or constraining. The paper concludes with reflections on the practical usefulness of the framework and concretes suggestions for further research, drawing on these convergence mechanisms and their interactions with boundary judgments on natural resources and sustainability.  相似文献   

11.
Analysis of the reproductive dynamics ofCalliptamus italicus during the past 100 years confirmed the dependence of locust invasions on the 11-year cycles of solar activity, which was previously known for other gregarious locusts. Over a considerable part of the species range, the onset of mass reproduction is promoted by a hot and droughty spring and summer. The scale of the outbreak is determined by local conditions in the foci of reproduction. The current global warming is characterized by an unstable, drastically varying climate with a trend toward aridity in many regions. If this trend persists for several decades, we may expect an increase in the periods ofC. talicus mass reproduction and in the persistency and extent of damage inflicted by locusts on vast Palearctic areas.  相似文献   

12.
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   

13.
Published results of comprehensive hydrochemical and hydrobiological studies of water bodies in the taiga zone of northwestern Russia were analyzed to estimate the lowest values of water pH at which individual zooplankton species had been recorded. On this basis, the most significant species indicative of surface water acidification were identified and a scale of their distribution depending on the degree of acidification was compiled.  相似文献   

14.
The ecological phytoindication scales proposed by Tsyganov (1983) were used for characterizing biotopes at the northern limit of the distribution of three nemoral species:Ajuga reptans, Asarum europaeum, andPulmonaria obscura. Regional ecological amplitudes of the model species were determined. The environmental factors approaching the lower limit of species amplitudes in Tsyganov's scales were classified as unfavorable.  相似文献   

15.
The causes and ecological consequences of alien plant species invasions in the Southern Urals are analyzed. Aggressive invasive species of North American origin??Ambrosia trifida L., A. psylostachya DC., Cyclachaena xanthiifolia (Nutt.) Fresen., Hordeum jubatum L., Oenothera biennis L., Bidens frondosa L., etc.??have invaded synanthropic and natural plant communities and became dominant, with their proportion varying from 10 to 99%. The biomass of these plants may reach 6 kg/m2; density, more than 1000 shoots per square meter; and seed production, up to 30000 seeds per plant, which explains their dominance in communities. The ecological hazard they pose lies in the displacement of native species, overgrowing of disturbed land areas, and allergenicity of their pollen.  相似文献   

16.
17.
Integrated studies on the temperature regime in a limestone outcrop area have been performed, including analysis of the latitudinal trends and dynamics of direct solar radiation input onto slopes of different exposures and the redistribution of temperatures depending on mesotopographic features of the slopes. Assessment of the diversity of ecological conditions in this model landscape has shown that about 3.3% of its area is potentially suitable for the formation of a relict lithophytic floristic assemblage.  相似文献   

18.
RTP "ATOMFLOT" is a civilian nuclear icebreaker base located on the Kola Bay of northwest Russia. The objectives of this study were to determine the distributions of man-made radionuclides in the marine environment adjacent to the base, to explain the form of the distributions in sediments and to derive information concerning the fate of radionuclides discharged from ATOMFLOT. Mean activity concentrations (d.w.) for surface sediment, of 63 Bq kg(-1 137Cs, 5.8 Bq kg(-1) 90Sr and 0.45 Bq kg(-1 239,240)Pu were measured. Filtered seawater activity levels were in the range of 3--6.9 Bq m(-3) 137Cs, 2.0-11.2 Bq m(-3) 90Sr, and 16-40 m Bq m(-3), 239,240Pu. Short-lived radionuclides were present at sediment depths in excess of 10cm indicating a high degree of sediment mixing. Correlations of radionuclide activity concentrations with grain-size appear to be absent; instead, the presence of relatively contaminated sediment appears to be related to the existence of radioactive particles.  相似文献   

19.
The results of a study of the content of heavy metals in fruticose epiphytic lichens in the taiga zone of the European Northeast of Russia (Republic of Komi) are presented. The content of elements in lichens in this area is at the background level for the northern part of Eurasia. A series of accumulated heavy metals in lichen have been established. Metal distribution mapping has made it possible to differentiate areas with respect to the level of their accumulation. The accumulation of mercury by lichen increases and the contents of manganese, coper, and cadmium decreases from the southwest to the northeast.  相似文献   

20.
Studies on the population structure and dynamics of the stone centipede Monotarsobius curtipes C. Koch in soils of the northern Kola Peninsula have shown that, with respect to abundance and biomass, this species is a dominant of the soil macrofauna and, in particular, of the trophic group of zoophages. Life in high northern latitudes does not disturb the sex and age structure of populations but limits the reproductive activity of these centipedes. Specific biological features of M. curtipes at the northern periphery of its range include the absence of repeated breeding, completion of several developmental (age) stages within a short growing season, and long ontogeny involving several winterings.  相似文献   

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