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1.
The data on the biological diversity, bioecological features, and geographic variations of segetal plants in the Middle Urals are presented for the first time. It has been shown that apophytic and anthropophytic groups are equally represented among them. Each group is characterized, and the phytocoenotic activity of segetal plants is considered.  相似文献   

2.
Analysis of zonal patterns in the formation of synanthropic vegetation has shown that the intensity of manifestation of its zonal differentiation increases with the advancement of the successional stage of synanthropic communities. The rate of successional processes in these communities depends on the initial (potential) type of vegetation in the territory of the city.  相似文献   

3.
The prevalence of arbuscular mycorrhizas and abundance of mycorrhizal fungi in the roots of herbaceous plants with different types of Grime-Ramenskii’s ecological strategies (competitors, ruderals, and stress tolerators) have been studied in the Middle Urals. The closest association with arbuscular fungi has been observed in species with a competitive strategy. Compared to them, stress-tolerant species are characterized by lower abundance of mycorrhizal fungal hyphae in the root system, while ruderal plants include a relatively large proportion of nonmycotrophic species showing no interaction with arbuscular fungi.  相似文献   

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The population dynamics of moose, wild boar, and roe deer in the Middle Urals and changes in the proportion of females among the animals taken by hunters were analyzed. For all the three species, a tendency toward selective hunting for females was revealed. In this situation, the proportion of females in a population decreases with time, and its reproductive potential is impaired.  相似文献   

6.
The results of studies on small mammal bone assemblages from seven cave-type sites on the Shchugor and Kozhim rivers are presented. Four stages in the development of small mammal fauna in the Nether-Polar Urals are described, which correspond to the Aller?d, Younger Dryas, Early Holocene, and Subatlantic periods. The moderately cryohydrophilic fauna of the Aller?d was replaced by an atypically ??mild?? xerophylic community in the Younger Dryas. In the Early Holocene, its structure still included considerable proportions of tundra species, which, along with forest species, were also found in the subfossil assemblage from the Subatlantic. It is shown that the transformation of the small mammal fauna in the above sites had a specific pattern, compared to that in other regions of northeastern Europe and to the dynamics of the natural environment and climate.  相似文献   

7.
The results of studies on the humus state of soils in agrosystems of the Middle Urals (1984–1997) are described. It is shown that the change of agricultural technologies (crop rotation, doses of organic fertilizers, etc.) transforms environmental conditions and the direction of humus formation processes. Parameters such as the concentrations of humus and water-soluble carbon and soil potential for humus accumulation reliably characterize the humus state of arable soil and allow the mobility and migration rate of humic substances to be monitored.  相似文献   

8.
Steppes at the northern limit of their distribution are a convenient object for studying climate-induced modifications of the environment, being sensitive to regional climate changes. Over the past 46–47 years, herbaceous vegetation in the study steppe areas has been replaced by shrubs and trees. Petrophytic steppes on hilltops and stony knolls, where conditions are not favorable for tree growth, has proved to be more resistant to such changes. In these habitats, however, the influence of surrounding forest phytocenoses has also resulted in a gradual decrease in the proportions of species from the steppe and forest–steppe floras in the structure of communities and the invasion by species typical of forest vegetation.  相似文献   

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The kinetics of accumulation of essential and toxic trace elements (TE) in vitally important organs were studied in small mammals typical of the Middle and Southern Ural fauna. The results revealed a discrepancy between the increased uptake of Cd, Zn, Pb, and Cu by animals and the virtually constant concentrations of heavy metals (HMs) in their organs, which could be explained by the existence of special elimination systems activated upon excessive HM uptake. It is shown that HM accumulation in animal tissues is energy-dependent and species-specific, and the effects of highly toxic TE correlate with physiological processes.  相似文献   

11.
Degradation of fur hunting in the mid-1990s allowed the impact of hunting on some species of predatory mammals to be estimated. The numbers of sables, martens, foxes, and lynx were demonstrated to slowly decrease in the period of intense hunting; after pelt trade ceased, the numbers of sables, martens, and foxes increased by a factor of three within 15 years. Ermines and Siberian weasels had not experienced a substantial hunting pressure; changes in their numbers were caused by other factors.  相似文献   

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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   

14.
The abundance, density, structure, and dynamics of the populations of 11 rare orchid species are characterized on the basis of observations carried out in the eastern foothills of the Middle Urals from 1991 to 2002. The pattern of changes in the age structure of populations belonging to different ecobiomorphs is revealed. The concept of vegetatively oriented and generatively oriented age spectra of populations is proposed.  相似文献   

15.
Russian Journal of Ecology - Abstract—Some factors influencing C and N contents in fine plant roots were studied in the Middle Urals. They included ecological (edaphic) features of habitats;...  相似文献   

16.
Special aspects of solving certain key problems in the ecology of Quaternary mammals using materials from the Ural region are considered. Possibilities and limitations accounted for by specific features of the region are analyzed. The nature of “mixed” (mammoth, tundra-steppe, hyperborean) faunas and their diversity are considered in the context of questions related to trends in the dynamics of range boundaries and relative abundance of different mammal species during the Late Pleistocene and Holocene.  相似文献   

17.
The results of original studies and published data are used for evaluating the main responses of the avifauna of boreal forests to the combined effect of sulfur dioxide and heavy metals. It is shown that environmental pollution results in the reduction of species richness, biomass, and stability of the nesting bird fauna. In degraded areas, the structure of the bird community changes: (1) typical forest species are replaced by the species of open habitats, and (2) the proportion of species nesting in the upper tree layer decreases, whereas that of ground-nesting species increases.  相似文献   

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Periodic monitoring (by age stages) of the growth energy and health of trees has been performed in population cultures of white birches established on a half-sib basis (for the first time in Russia). The results show that the pattern of growth and development and the health (survival) of provenances tested in population cultures depend primarily on the ecobiological properties of birch species and also on the distance and direction of seed transfer.  相似文献   

20.
Specific features of root system formation in the main forest-forming species have been studied under conditions of natural regeneration or planting on large cinder dumps of district heat and power plants in the Middle Urals. Prospects for using these species for biological (forest) recultivation of cinder dumps are evaluated.  相似文献   

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